75745205 SRAL XD Technical Manual

Author : COO IPT MWR ProdM Code: TD-040203-1

Date : February 21, 2006 SRAL XD System Technical Description 1/65

SRAL XD System Technical Description

CODE: TD-040203-1

ISSUE/UPDATE: 21 February 2008

VERSION 2.0

SOURCE: COO IPT MWR ProdM

Author : Com MN MW BPM BLM Code: TD-040203-1

Date : February 21th, 2008 SRAL XD System Technical Description 2/65

INDEX

1. Introduction ................................................................................................................................4 1.1. Scope.............................................................................................................................. 4 1.2. Related Documents......................................................................................................... 4 1.3. Revision Information........................................................................................................ 4

2. System Overview .........................................................................................................................5 2.1. Introduction ..................................................................................................................... 5 2.2. Indoor Unit....................................................................................................................... 6

2.2.1. IDU Plug-in .............................................................................................................. 7 2.2.2. IDU SingleBoard2.................................................................................................... 8 2.2.3. Outdoor Access Unit................................................................................................ 9

2.3. Outdoor Unit .................................................................................................................. 10 2.3.1. Normal Density ODU ............................................................................................. 10 2.3.2. High Density enhanced ODU................................................................................. 10

2.4. Configurations ............................................................................................................... 11 2.4.1. Unprotected terminal ............................................................................................. 11 2.4.2 Protected terminal ..................................................................................................... 11 2.4.3 Add-Drop/Repeater ................................................................................................... 13 2.4.4 2x(1+0) ...................................................................................................................... 14 2.4.5 Ring........................................................................................................................... 14

2.5 Installation ..................................................................................................................... 15

3. System Description....................................................................................................................20 3.1. IDU Plug-In.................................................................................................................... 20

3.1.1. Access Card .......................................................................................................... 21 3.1.2. Controller ............................................................................................................... 21 3.1.3. BaseBand.............................................................................................................. 22

3.2. IDU SingleBoard2.......................................................................................................... 24 3.3. Outdoor Access Unit...................................................................................................... 25 3.4. Outdoor Unit .................................................................................................................. 26

3.4.1. ODU ND ................................................................................................................ 27 3.4.2. ODU HD/HP .......................................................................................................... 28 3.4.3. ODU HDe .............................................................................................................. 29

3.5. Frequency Setting ......................................................................................................... 29 3.6. Output Power ................................................................................................................ 30

3.6.1. Coupling loss ......................................................................................................... 31 3.7. Radiating System .......................................................................................................... 32

4. Cross Connect Functionality....................................................................................................35 4.1. Cross Connection Matrix on IDU PI 16xE1 .................................................................... 35 4.2. Cross Connection Matrix on IDU Plug-in 32xE1 ............................................................ 36 4.3. Preservation of the cross-connection matrix .................................................................. 37

5. Ethernet functionalities ............................................................................................................38 5.1.1. Switching ................................................................................................................... 40 5.1.2. Filtering ..................................................................................................................... 40 5.1.3. Forwarding ................................................................................................................ 40 5.1.4. Scheduling................................................................................................................. 42

6. Dynamic Modulation................................................................................................................44 6.1. Basic behaviour............................................................................................................. 44 6.2. Switch-over criteria........................................................................................................ 45 6.3. S/N measurement ......................................................................................................... 45



6.4. Working mode change criteria ....................................................................................... 46 6.5. Working mode parameters ............................................................................................ 47

7. Management .............................................................................................................................48 7.1. DCN .............................................................................................................................. 48

7 Network Management System..................................................................................................52 7.1 Security ......................................................................................................................... 53

7.1.1 Access Security ......................................................................................................... 53 7.1.2 Protocol ports security ............................................................................................... 53 7.1.3 Same Admin password for FTP/TELNET/TNMP........................................................ 54 7.1.4 SSH on FTP / Telnet session..................................................................................... 54 7.1.5 Accounting log........................................................................................................... 54

7.2 Configuration management: .......................................................................................... 54 7.3 Commissioning Facilities: .............................................................................................. 55

7.3.1 Long period performance monitoring recording.......................................................... 55 7.3.2 Time switched forcing ................................................................................................ 55 7.3.3 Local History Log....................................................................................................... 56 7.3.4 Measurement ............................................................................................................ 56 7.3.5 Performance Monitoring ............................................................................................ 56

7.4 Fault management: ....................................................................................................... 58 7.5 Maintenance.................................................................................................................. 59 7.6 SNTP Support ............................................................................................................... 59 7.7 NAPT on F interface...................................................................................................... 60 7.8 OSPF ............................................................................................................................ 60

8 Software Download...................................................................................................................61

9 Engineering Order Wire...........................................................................................................62

10 VoIP...........................................................................................................................................63

11 Alarm converter ........................................................................................................................64



1. Introduction

1.1. Scope Scope of this document is to give an overview of SRAL XD product family focusing on architectural aspect and main features.

1.2. Related Documents In order to have a complete description of the performance of the equipment refer to SRAL XD System Technical Specification (TS-310706-1) For a complete description of the available features for each Software Version Release refer to the latest version of Customer Feature List and Customer Release Note

1.3. Revision Information The here listed configuration and feature are related to the last SVR released according.

Issue Date Author Notes

1.0 February 2004 F. Tammaro First Issue

2.0 March 2004 F. Tammaro Second Issue

3.0 March 2004 F. Tammaro Third Issue

4.0 August 2004 F. Tammaro Update: Ethernet Version

5.0 November 2004 D. Cattelan

Update: 32xE1 version and E3 version

6.0 January 2005 D. Cattelan Update

7.0 April 2005 D. Cattelan Update

8.0 May 2005 D. Cattelan Update: new values ODU HDe

9.0 June 2005 F.Tammaro Update: Outdoor Access Unit

10.0 August 2005 F.Tammaro Update

11.0 August 2006 F.Tammaro Update up to SVR 3.7

11.1 August 2006 V. Colaleo/D. Cattelan Revision

12.0 October 2006 V. Colaleo/D. Cattelan

Update to SVR 3.8 and IDU SB2 insertion

13.0 February 2008 F.Tammaro Update up to SVR 3.10



2. System Overview

2.1. Introduction SRAL XD is a PDH MW equipment able to transmit a traffic load from 2xE1 to 32xE1 in the frequency bands 7- 38 GHz according to ETSI radio channel arrangements. The equipment adopts a split configuration composed of one Indoor Unit connected to one or two Outdoor Units, by means of a coaxial cable. The ODU is directly connected to the rear of antenna by means of four retaining latches without using any waveguide.

The IDU (Indoor Unit) provides traffic and auxiliary channels interfaces and performs baseband and control processing independently from operating frequency. The ODU (Outdoor Unit) performs the Mo-Demodulation and houses the RF Tx/Rx unit. It is independent from traffic capacity. The following system configurations are available:

(1+0) unprotected terminal

2x(1+0) unprotected terminal

Add-Drop / Repeater

Ring

(1+1) hot stand-by protected terminal

(1+1) Frequency Diversity protected terminal

(1+1) Polarization Diversity protected terminal



2.2. Indoor Unit

The indoor unit provides the tributaries input and output interfaces as well as interfaces for service channels, network maintenance facilities, alarms and connection to the power supply.

The Indoor Unit performs baseband processing, scrambler/descrambler and FEC functionalities.

The IDU also equips the Switching logic offering protection against multipath fading and hardware failure.

The unit adopts a 1U high case that can be mounted in a 19 or 600 mm rack. All the connectors for the traffic, service channels and maintenance operation are in the front of the equipment.

Three different IDU versions are available

Plug-In Single Board2 Outdoor Access Unit

IDU Plug-in

IDU SingleBoard2

Outdoor Access Unit



2.2.1. IDU Plug-in

The Plug-In version has been designed to provide a full set of configurations:

(1+0)

2x(1+0) unprotected terminal

Add-Drop / Repeater

Ring

(1+1) hot stand-by protected terminal

(1+1) Frequency/Polarization Diversity protected terminal The IDU adopts a modular architecture composed of four cards housed in a 1U high shelf:

Access Card : 16xE1, 32xE1, 1xE3+E1, 4xFE+ 8xE1, 3xFE+1xGE+16xE1

Controller Card

Base Band 16E1:16xE1 (to be used w/ 16xE1 Access Card and 4xFE + 8xE1 Access Card)

Base Band 32E1:32xE1 (to be used w/ 32xE1 Access Card and 3xFE+1xGE+16xE1 Access Card)

Base Band E3 :E3+E1 (to be used with 1xE3+E1 Access Card) The listed configurations are related to the maximum hardware capacity: the wanted set of features can be enabled by means of a user fee mechanism. In the following figure the different cards are shown and the description of the relevant interfaces is provided.

V-BUS SRAL XD

12

ALMs

06

2 M bit/s I/O TRIBUT ARIES 916

PS

CAUTION Vbatter y

ODU CABLE A H B L H B D U '

0103

020409 11 10

2 M bit/s I/O TRIBUT ARIES 1-8 ALMs LAN 1 USER/D ext LAN 2 Dext LAN 3 LAN 4

I 0

06 07 08B A

06 07 08

B A

or

ODU CABLE CAUTION Vbatter y

H A C C B H L B C U O D '

PS ' T S E T W M / N J C / M

s Q-LAN V-LAN

LCT

06 07 08

2 M bit/s I/O TRIBUT ARIES 18

ALMs USER/D ext USER/D ext

B A

I 0 or or

0807

B A

2Mbit /s USER/D ext

34M bit/s Dext

I 0

IDU Plugin: cards and interfaces



Ref Description Functions

POWER SUPPLY

A I/O POWER ON/OFF

01 PS PS 1ST

BASE BAND

02 PS PS 2ND

BASE BAND

IF

03 ODU CABLE 1ST

IDU/ODU CONNECTION

04 ODU CABLE 2nd

IDU/ODU CONNECTION

TRIBUTARY

05a 2MB/s I/O TRIB.s 18

05b 2MB/s I/O TRIB.s 916 2Mb/s 75/120 Ohm

05c

2MB/s I/O TRIB.s 18 2MB/s I/O TRIB.s 916 2MB/s I/O TRIB.s 1724 2MB/s I/O TRIB.s 2532

2Mb/s 75/120 Ohm

05d 34 Mbit/s 34 Mbit/s 75 Ohm

05f LAN1..LAN4 10/100 BaseT

ALARMS

06 ALARMS ALARMS

SERVICE

07 USER/Dext 1st 64 Kb/s V11 Data Channel

08 USER/Dext or Dext 2nd

64 Kb/s V11 Data Channel

05e 2Mb/s 2Mb/s 75 Ohm

SETTING

09 LCT F interface expansion for PC

B Back-up memory key

MANAGEMENT SYSTEM

10 Q-LAN 10/100 BaseT

11 V-LAN 10 BaseT

12 VBUS 128 Kb/s Data Channel

Such architecture allows to upgrade an unprotected configuration, just adding in the same shelf an additional base-band card which can be individually supplied. In case of failure in a Protected configuration the BaseBand can be replaced without traffic interruption. In this version the Baseband Card also houses the Hitless Switch logic providing an error free connection in case of fading.

2.2.2. IDU SingleBoard2

The SingleBoard2 IDU adopts a monolithic architecture, consisting in a single replacement unit, tailored on a selected set of features. It is available in the following hardware versions:

8xE1 (1+0)

16xE1(1+0)

16xE1(1+1)Hsby



The listed configurations are related to the maximum hardware capacity: the wanted set of features can be enabled by means of a user fee mechanism.

2.2.3. Outdoor Access Unit

The Outdoor Access Unit implements all access and baseband functions in a waterproof case suitable for outdoor installation. The mechanical structure of the OAU consists of a compact sealed box suitable for wall mounting and pole mounting. Suitable flanges are foreseen for the installation of the OAU into ETSI and/or 19 rack.

Ref Description Functions

POWER SUPPLY

A I/O POWER ON/OFF

01 PS POWER SUPPLY

IF

02 ODU CABLE 1ST

IDU/ODU CONNECTION

03 ODU CABLE 2nd

IDU/ODU CONNECTION

TRIBUTARY

04a 2MB/s I/O TRIB.s 18

04b 2MB/s I/O TRIB.s 916 2Mb/s 75/120 Ohm

ALARMS

05 ALARMS ALARMS

SERVICE

06 USER/Dext 1st 64 Kb/s V11 Data Channel

SETTING

07 LCT F interface expansion for PC

B Back-up memory key

MANAGEMENT SYSTEM

08 Q-LAN 10/100 BaseT

09 V-LAN 10 BaseT

07 LCT F interworkng-S channel

CONNECTION PANEL

GROUNDING POINT

90

POWER SUPPLY

CONNECTOR

DIMENSIONS IN MILLIMETERS

PC CONNECTION CONNECTOR



2.3. Outdoor Unit

The Outdoor Unit (ODU) is in charge of the following tasks: 1. IDU-ODU cable interface management (pwr supply and in/out base-band signals); 2. Modulation of base-band digital signal received from the IDU; 3. Demodulation of received RF signal and delivery of recovered base-band signal to IDU; 4. Supervision and configuration/management of the ODU; 5. Management of the communication channel from/to IDU CONTROLLER. The Outdoor Unit adopts a Frequency Division Duplexing technique as showed in the relevant ETSI recommendations. RF transmitter and Receiver frequencies can be set by the user by means of SW command. Any change of Tx (Rx) frequency automatically involves the change of Rx (Tx) frequency according to the ODU shifter. Three ODU versions are available:

2.3.1. Normal Density ODU

Provides a 4CPM modulation format for 2/4/8/16x2Mbps Traffic Capacity, with a channel spacing of 3.5/7/14/28 MHz

2.3.2. High Density enhanced ODU

Provides two different modulation formats selectable via software: 4 QAM or 16 TCM. The 4QAM modulation allows traffic capacity of 4/8/16x2Mbps with a channel spacing of 7/14/28 MHz. The 16TCM modulation is provided for payload of 8/16/32x2Mbps with a channel spacing of 7/14/28 MHz.

(DOWN VIEW)

(SIDE VIEW)

(FRONT VIEW)

267

238

281

123

ODU ND and HDe



2.4. Configurations

2.4.1. Unprotected terminal

In this configuration the equipment consists of:

One ODU One Antenna One IDU One coaxial cable for IDU-ODU interconnection

2.4.2 Protected terminal

The equipment consists of:

Two ODUs One or two antennas One IDU One coaxial cable for each IDU-ODU interconnection Following options are available for protected configuration:

Hot Stand-by

Frequency Diversity

Polarization Diversity

1+1 Hot Standby

This method offers protection against HW failures providing two independent TX/RX chains.

In (1+1)HSby one transmitter is working, while the other one is in stand-by; both receivers are active and the best ODU source is selected.

When an HW failure is detected the system actuates the hardware switch:

Tributaries

(1+0)



On IDU Plug-in, TX (BB+ODU) and RX chain (BB+ODU) are switched independently according to the occurence of the fault

On IDU Single Board2, both TX (BB+ODU) and RX chain (BB+ODU) are switched at the same time

This switch cannot avoid error bursts during the protection switching, because it is a hardware switch, controlled by alarm signals generated by already happened hardware defects

Both ODUs are connected to a single antenna via a power splitter, balanced (3dB symmetric loss) or un-balanced (stand-by channel loss ~ 10 dB, main channel loss ~ 1 dB).

Either remote or separate mounting is available.

Alternatively, each ODU can be connected to an individual antenna.

.

Tributaries

(1+1)Hsby On Double Antennas

Main

Hsby

Tributaries

(1+1)Hsby On Single Antenna

Main

Hsby



1+1 Frequency Diversity

This method offers protection against selective and temporary link quality degradation.

In (1+1) Frequency Diversity, both radio paths are active in parallel using different frequencies; this method, based on memory buffer that guarantee the bit to bit alignment, can offers error free protection against fading (via a hitless switch) up to 100dB/sec.

Both two antennas and single antenna (dual polarized) mounting arrangements are available.

(1+1) Polarization Diversity adopts the same concepts of FD, but in this case the same RF signal is transmitted on two different polarizations (H/V) by means of a single double polarized antenna.

2.4.3 Add-Drop/Repeater

Add/Drop-Repeater system type is characterized by two different radio directions each one employs one ODU. This system allows partially dropping and/or adding tributaries to the radio payload (ADD/DROP mode) or to redirect the whole payload from one radio direction to another one without any access tributary management (Repeater mode) This configuration is used in the sites where local traffic is collected.

Tributaries

PassThrough

AddDrop

Localy AddDropped

Tributaries

(1+1)Frequency Diversity

F1

F2



2.4.4 2x(1+0)

This solution provides an equivalent two radios back-to-back configuration. In this case the two directions are treated as separated ones but they are managed by just one IDU

2.4.5 Ring

RING system type (supported only by 32xE1units) is characterized by two different radio directions and it employs two ODUs. Its function is to perform a path protection (SNCP like mechanism): the payload is transmitted towards the two opposite directions, but it is received from the best direction; the choice of the receiving direction is based on AIS signal.

For each E1 terminated on the Access side (A), there is a switch selecting the best of the two signals coming from the two Base Band units; the transmitted signal is duplicated from the Access side towards both the BB units. B and B may be different E1 lines on the two BB units (for example, line 3 on BB1 and line 26 on BB2).

Tributaries

Ring

B B

AB

Tributaries E

2X(1+0)

Tributaries W



Each switch is independent from the other ones and switching takes places according to AIS detection at E1 level; for each protected connection it is possible to set the switch in automatic mode (switch based on path AIS detection) or to force the position on one of the two sides by LCT/NMS. In this way any physical interruption in a Network ring configuration can be bypassed.

2.5 Installation

Indoor unit fits in 19 racks and cabinets, as well as in ETSI cabinets or directly on a desk/wall. The interconnection between the outdoor unit and the indoor part is a single coaxial cable carrying full duplex traffic, DC power supply, service traffic as well as operation and maintenance data. The ODU can be either mounted directly to the antenna or mounted separately and connected by a flexible waveguide. Two Outdoor units, in a protected (1+1) configuration, can be connected to a single antenna using a power splitter. In the following pictures, several installation alternatives regarding ODUs and antennas are shown:



BRAIDED COAXIAL CABLE

INTEGRATED ANTENNA

FLEXIBLE WAVEGUIDE

VERTICAL (1+0) FRAME

ODU

(1+0) Not Integrated

INTEGRATED ANTENNA

OUTDOOR ASSEMBLY

(1+0) Integrated



In the following pictures, examples regarding fully outdoor system are shown:


(1+1) INTEGRATED SUPPORTING FRAME

ODU

(1+1) Integrated

INTEGRATED ANTENNA

INTEGRATED ANTENNA

ODU

(1+1) FRAME

FLEXIBLE WAVEGUIDE

(1+1) Not integrated



IN/OUT BRAIDED COAXIAL CABLE

OAU UNIT

(1+0) Integrated



(

INTEGRATED ANTENNA

FLEX WAVEGUIDE

VERTICAL (1+0) FRAME

OAU UNIT

ODU


(1+0) Not Integrated



3. System Description

This section describes the system main units.

3.1. IDU Plug-In The IDU Plug-In adopts a modular architecture composed by:

The Access Card that represents the physical access of the equipment for the Tributary streams from the public network, it also includes all the alarms and service channels interfaces. A memory key containing the configuration parameter is equipped onto this unit.

One Controller Card that includes all the control and supervisory functions. It also contains a EEPROM for inventory/user data and alarm history

One BaseBand Card, that includes all the base band processing, cable protection and IDU-ODU auxiliary service channel management

The modular architecture allows obtaining all the other configurations of the IDU (2(1+0), A/D-RPT, Ring, (1+1) FD, PD and H/S) by duplicating only the BaseBand unit.

The cards are housed in a 1U high subrack which provides electrical interconnections between them by means of its backplane.

A 1U Subrack B Access Card C Controller D BaseBand 1 E Baseband 2(opt.)

Tributaries

BB2

BB1

Access

Controller

Alarm Service

To ODU



3.1.1. Access Card

The Access card is responsible of the following tasks: Physical interface management of auxiliary channels (User/D external/Alarms) and Tributaries

Interface. Each tributary can be enabled or disabled. When a tributary is enabled, hardware must provide fault monitoring associated to each tributary, including AIS IN, LOS, Code error and AIS OUT detection. Auxiliary channel fault monitoring is not provided. The Access Board allows local and remote loopback for each tributary signal.

Cross connect function allows to cross-connect the tributaries signals. Each local E1 input port

can be switched to any E1 tributary output port, at the other side of the link. Cross connect E1 configuration must be set by using suitable software commands, issued via LCT or Netviewer. E1 tributary can be also connected in path protection mode, used only in Ring system type, allowing the selection of the E1 signal between the two received signals according to the AIS selection criteria.

Stuffing / destuffing Multiplexing of tributary signals (after the stuffing block) into an aggregate frame for backplane

connection. De- multiplexing of the same signals is required in the opposite direction on the aggregate frame received from BaseBand boards.

Access Card also houses the memory key containing the licence fees (Configuration: (1+ 0) or (1+1)1 / Traffic Capacity: NxE1 / Modulation format: HD or ND) and all Configuration Parameters. Four versions are available: 16xE1 Version: Traffic capacity up to 16xE1 1xE3 Version: E3 traffic capacity and a 2Mbps wayside channel 32xE1 Version: Traffic capacity 32xE1 8xE1+4xFE Version: Mixed TDM and Ethernet traffic interface up to 32Mbps 16xE1+3xFE+1xGE Version: Mixed TDM and Ethernet traffic interface p to 64 Mbps All Access Card versions provide the same service channel interfaces:

2 x User/ Dext Channel (Sw selectable)

Alarm interfaces.

3.1.2. Controller

The Controller implements the system control functionalities. The main functions are: Collection of alarms and working parameters from the system units (IDU and ODU);

transmission of this information to a local PC or to a network supervision system Activation of system commands coming from a local PC or from a network supervision system

(status forcing, modification of equipment parameters, etc.)

1 (1+1) licence enables 1+1, Ring, 2x(1+0) and Add-drop/Repeater System Types



Storage on a Memory key of the system configurations and on EEPROMs the inventory / user data and alarms history.

Routing of messages among controllers and the network supervision system manager Electrical and protocol translation between the radio environment (which uses a proprietary

protocol channel, embedded in the radio frame, to transport management information) and the supervision system (which requests that this information is available on a public connector, with a standard protocol).

Measuring the IDU temperature2: the measurement has 1C resolution and is updated once

every 15 s.

Functional blocks of the IDU are shown in the following figure:

3.1.3. BaseBand

The unit carries out the following functions: Regeneration of the 2 Mbit/s input tributary signals in compliance with Rec. G.703 and HDB3 ->

NRZ conversion Generation of the aggregate frame and multiplexing of the input tributary signals into one main

stream Scrambling (212-1 length stream seeded at the beginning of each frame, 215-1 for E3) FEC insertion (Reed Solomon type, with a correction capacity of up to 5 errored bytes per frame) Interleaving

2 functionality supported by Controller Unit code 634-001/74 from HW edition n8

LoopBack &

AIS Logic

CK Recovery

Fault Moniotring

Line Decoder

D- Emb Dropping

LoopBack

AIS

Inserction Detection

Line Decoder

Dejjitter PLL

D- Emb aDDING

Stuffing Mux

BackPlane I/F

Stuffing Mux

BackPlane I/F

DeStuffing DeMux

BackPlane I/F

DeStuffing DeMux

BackPlane I/F

External I/F

DEmb to Controller

AIS In/Los

DEmb from Controller

External I/F

Protection Logic

Access Card functional architecture



Generation of a 128 kbit/s auxiliary service channel for the transmission of data channels, alarms etc., between the IDU and the ODU (inserted into the main stream)

Generation of the switching command for the Tx HW switch Automatic level control on the signal incoming from the ODU. Power Supply conversion and distribution The unit also comprises all the circuitry necessary to: Carry out the hitless switching function between the two aggregate signals when the equipment

has been set to the protected configuration. Send and receive the following signals from the ODU via the connecting coaxial cable:

Aggregate stream power supply voltage for the ODU

Three BaseBand versions are available depending on Multiplexer functions: BaseBand 16xE1 BaseBand 32xE1 BaseBand E3 Each of these cards has to be used in conjunction with the relevant Access Card. The Ethernet Access Card works in conjunction with BaseBand 16xE1.

MUX / DEMUX

Scrambling FEC

Interleaving

Hitless Switch

I/F cable

Service Drop-Insert

to ODU

HW Control Logic

DC/DC

to CTRL

From access unit

From access unit

Power Supply

to Access

to ODU

Secondary Voltage

Baseband Card functional architecture



3.2. IDU SingleBoard2 The SingleBoard2 IDU adopts a monolithic architecture, consisting in a single replacement unit, tailored on a selected set of features. It is available in the following hardware versions: 8xE1 (1+0) 16xE1(1+0) 16xE1(1+1)Hsby The listed configurations are related to the maximum hardware capacity: the wanted set of features can be enabled by means of a user fee mechanism, within this constraint. Protected Configuration is provided with ODU redundancy only. In the Figure the block diagram of the IDU architecture is shown.

The Power Section provides the interface to the external Power Supply. The Control Section is in charge of the management of the complete system, and provides the interfaces to the supervision systems. Tributary Section interfaces the equipment to external tributaries and user-available signals. The BB section is in charge of the following tasks: Regeneration of the 2 Mbit/s input tributary signals in compliance with Rec. G.703 and HDB3 ->

NRZ conversion Generation of the aggregate frame and multiplexing of the input tributary signals into one main

stream Scrambling (212-1 length stream seeded at the beginning of each frame, 215-1 for E3) FEC insertion (Reed Solomon type (152,142), with a correction capacity of up to 5 errored bytes

per frame) Interleaving Generation of a 128 kbit/s auxiliary service channel for the transmission of data channels, alarms

etc., between the IDU and the ODU (inserted into the main stream) Automatic level control on the signal incoming from the ODU. Power Supply conversion and distribution

BaseBand Section 2

(Opt)

PS Section

Tributary Section

Control Section BaseBand Section 1

POWER SUPPLY BUS

SIGNAL BUS

CONTROL BUS

PS User/Dext TRIB Q-LAN V-LAN LCT ALM IF CABLE IF CABLE



3.3. Outdoor Access Unit

The Outdoor Access Unit implements all access and baseband functions in a waterproof case suitable for outdoor installation. The mechanical structure of the OAU consists of a compact sealed box suitable for wall mounting and pole mounting. Suitable flanges are foreseen for the installation of the OAU into ETSI and/or 19 rack. The OAU works with all ODU versions in all the frequency bands. The connection between the waterproof unit and the ODU is performed by means of a coaxial cable carrying traffic, power supply and management information.



3.4. Outdoor Unit The ODU is the system part in charge of RF processing of the signal. It is connected to the IDU by a coaxial cable and to an antenna by means of four latches providing fast and easy mounting. The main functions of the ODU are: IDU-ODU interface management :

Performs the IDU-ODU physical interfacing, allows splitting power supply input signal and the cable frame to demux the radio payload which must be transmitted to modem section and the cable overhead used for IDU-ODU interface management and for ODU control.

IF+RF block: it is responsible for up/down conversion of In-Phase and Quadrature signals to

the desired RF/IF frequency. Modulation/Demodulation of base-band digital signal received/transmitted from/to the IDU Supervision and configuration/management of the ODU Management of the communication channel from/to IDU CONTROLLER RF processing: Transmitting and receiving of the modulated signal

The Outdoor Unit adopts a Frequency Division Duplexing technique as showed in the relevant ETSI recommendations. RF transmitters and Receivers frequencies can be set by the user through the system Controller by means of SW command. Tx and Rx frequencies are joined by the shifter value: any change of Tx (Rx) frequency automatically involves the change of Rx (Tx) frequency according to the ODU shifter. The figure below shows the ODU functional view.

The RF unit and the Duplexer are the only frequency dependent blocks. Within a frequency band, typical a quarter of band tunability is obtained trough independent Tx/Rx synthesized VCOs with a step size of 250 kHz. Three external interfaces are available:

Controller PS Section

CABLE I/F

MODEM IF Section

RF

DUPLEXER

POWER BUS

CONTROL BUS

SIGNAL BUS

RSSI IDU / ODU CABLE ANTENNA



IDU/ODU Cable allows the connection of the coaxial cable carrying traffic power and supervision information

RSSI (Received Signal Strength Indicator) interface allows to get information about the

received RF signal level by a standard voltmeter as measuring instrument. Antenna interface allow the direct connection of an antenna or of flexible waveguide. It

adopts a standard PBR or PDR flange depending on the frequency bands. Three types of Outdoor Unit are available:

ODU ND ODU ND/HP ODU HDe

3.4.1. ODU ND

The Normal Density ODU is composed of two main boards and the duplexer. The MODEM board contains the following section:

Cable Interface

MODEM section: realizes a 4-level continuous phase modulation (4-CPM) of the baseband signal

Microprocessor

PS section The IF/RF Board is in charge of the following tasks: Up-conversion to desired radio frequency of the input base band signal, through preliminary

fixed IF up-conversion, delivered by Modem unit RF power transmission of up-converted signal to duplexer interface; Low-noise amplification of the RF signal from duplexer interface; Down-conversion to base band signal of the low-noise amplified RF signal, through preliminary

fixed IF down-conversion, and delivery it to the Modem unit



3.4.2. ODU HD/HP

The High Density/ High Performance ODU allows the selection, via SW, of the modulation format: 16 TCM or 4QAM. The Outdoor Unit is composed by the following subunits:

MicroWave Transceiver Front-end (MWTF): equips the microwave transmitter, receiver, VCOs and control board.

Dual UHF VCO: Is a part of the synthesizer used to synchronize the MW VCOs. Modem/IF: includes dual IF processing, modulation and demodulation system, dual PLL

low frequency synthesizer, ODU hardware controller. Power supply: Converts the DC voltage to the voltages required by other subunits and

provides alarm for failures. It extracts also the DC voltage from the cable and insures the primary lightning protection.

Filter diplexer: insures the tunability according to the frequency

VCO

? C

MODEM UNIT IF/RF SECTION

AGC

ATPC

DUPLEXER

XN

XN VCO

VCO SINTH TX

SINTH RX

M O D E M

LN

Power Section

Cable I/F

C

RSSI

I F C A B L

E

ANTENNA I/F



The aggregated signals, coming/sent from/to the IDU are treated in the Modem/IF subunit. The IF signal is filtered and sent to the transmitter to be up-converted to the microwave band. An output power control facility moves the transmitted power level in Output Power range. The Rx IF signal, coming from the receiver is demodulated and sent to the IDU. The IF unit houses the cable equalizer, the PLL circuits, a frequency reference oscillator (TCXO) and a microprocessor controller unit for the management of the hardware inside the ODU. The dual VCO unit provides a very low phase noise UHF signals to synchronize a couple of RF VCOs placed in the Microwave Transceiver Front-end (MWTF). The MWTF interfaces the microwave filter diplexer which insures the required decoupling between transmitter and receiver subunits.

3.4.3. ODU HDe

This ODU, besides the same functionalities of ODU HD/HP3, provides also the support of 32xE1 capacity in 28MHz with 16TCM modulation. Moreover, it is fully backward compatible with ODU HD/HP, in order to be used as spare part of the previous family. The High Density enhanced ODU is composed of two main boards.

Modem unit: it is in charge for power supply function, control function, cable interface management and modem function (4QAM/16TCM modulation). This board contains all processing which is common for all RF bands

RF/IF unit: it is in charge for up and down conversion from the modulated signal to RF frequency. The RF/IF unit architecture is different for each band.

This type of ODU is mandatory with IDU PI 32xE1 version

3.5. Frequency Setting The system provides two different setting modes of the operating frequencies: Continuous frequency: The user can set for the transmission frequency every value comprised into the operating band of the equipment with a step of 250 Khz. It is necessary to set manually the values of the transmission and reception RF frequencies. It is sufficient to set one of the two RF

3 Except the 2xE1 capacity in 3.5MHz that is not supported

To/From Duplexer

MODEM/IF

UNIT

Power

Supply

MWTF

Dual VCO

To/From IDU



frequency values, because the system automatically calculates and sets the other one according to the shift frequency. The user can set every value of the frequency, but this value must be within the operating band of the ODU (TF Min and TF Max). Frequency plan: The user can arrange a channelling plan that stays inside the operating band of the equipment. The numbers of the channel are dependent on operating band and transmission capacity. Each couple TX Freq- RX freq is identified by a Channel Number that can be used to set the operating frequency.

3.6. Output Power

Two Output Power setting modes are provided: Fixed/RTPC This power setting mode allows the user to select the output power of Tx chain, with 1dB granularity, within the Output Power Range allowed by the ODU version. ATPC ATPC (Automatic Transmit Power Control) feature allows to modify the remote transmit power automatically, in order to limit interference while guaranteeing certain quality performance in the local radio unit, even if a fading event has affected the radio channel: the far side terminal sends a signal regarding the received signal level and the near side terminal adjust its transmit power in order to meet a wanted RSL (named ATPC Threshold, can be set by the user) on the far side. The remote ODU ask an increasing or decreasing of the TX power on the basis of the comparison of received signal power compared to ATPC Threshold value. If the received power is in the range ATPC_Th 3dB, the command transmitted to the remote side is not o modify the transmit power (note that the value 3dB is fixed). For lower received power levels the command is to increase the power (1 dB) whereas for higher power levels the command is to decrease the power (by 1 dB). In ATPC mode the output power can be modified in the range PminATPC PmaxATPC. The parameter Pmin ATPC can be set by the user in all ODU version. Pmax ATPC is fixed to maximum output power provided by the ODU for ND ODU, while it can be configured by the user for the ODU HD/HP and HDe by means of the parameter ATPC Range (note that PminATPC+ATPC Range has to be less or equal to PTmax provided by the ODU).

ATPC_Th

PmaxATPC

PminATPC

=3dB

1dB decreasing request

1dB increasing request

No modification

Received Power



3.6.1. Coupling loss

In (1+1) H/S System Type, if ATPC is disabled, it is necessary to specify the value of the coupling loss (Coupling Loss parameter) for the RF connection of ODU, since RF TX power should be the same for the active and protection chain. This value depends on the hardware used for the implementation of the (1+1) Hot-Standby protection (allowed range of RF couplers loss is between 0 dB and 15 dB). Coupling loss parameter is used to increase the internal Tx power of the same value of the RF coupling loss, in order to have the desired power level after the RF coupler. For instance, when the unbalanced coupler is used, the coupling loss parameter for the Stand-by ODU is set to 10 dB, so that when the switch occurs its tx power is increased of 10 dB (anyway it cant be raised over Pmax ; PS-by ODU =min (Pmax , PAct-ODU + 10)).



3.7. Radiating System

The system in both (1+ 0) and (1+1) configurations allows integrated as well as separately mounted antennas. In case of integrated mounting, the outdoor unit is directly mounted onto the rear of antenna without any waveguide connection. The antenna is provided with a bracket to be mounted on a pole. The antenna mounting supports the outdoor unit, which is easily removable by means of simple retaining latches.

In case of remote mounting, a flexible waveguide is provided for the connection of antenna to the ODU

(1+0) Integrated Mounting



The (1+1) hot stand-by configuration on a single antenna is provided by means of a coupler in Balanced or Unbalanced version. The supporting frame can be mounted directly on the rear of the antenna or separated (pole, wall).

Examples of integrated antenna mounting in (1+0)/ (1+1) configurations:

Polarization diversity is possible by means of a dual polarisation antenna.

PROTECTION COVER

PROTECTION COVER

O-RING

(1+1) Supporting frame for integrated antenna mounting



Daul Polarized Antenna Mounting



4. Cross Connect Functionality

The cross-connect functionality is available only for Plug-In version. It allows, by means of SW setting, to cross connect the tributary interface toward the Radio Interface, both in Unprotected and Protected configuration.

The functionality, available by LCT/Netviewer, is provided by a CrossConnect matrix that provides three interfaces:

Tributary Side Radio Side 1 Radio Side 2

4.1. Cross Connection Matrix on IDU PI 16xE1 Unrestricted Cross Connection functionality for all System Types (1+0, 1+1, Add-drop/Repeater) is provided.

Added tributaries: it is possible to add/drop all 16 Radio tributaries for each Radio side. Pass-through signals: it is possible to cross connect all tributary signals West side of any

position with tributary signals East side of any position

CrossConnect Matrix Layout



4.2. Cross Connection Matrix on IDU Plug-in 32xE1

For all system types (1+0, 1+1 Hot Stand-by/FD, A-D/Repeater, Ring) a full cross-connection matrix is supported: each of the 32 E1 lines of the Access (tributary) side can be connected to any of the 32 E1 lines Base Band side. In case of Ring system type with 32xE1 radio capacity the cross-connection matrix supports only 32 connections of any type (theoretically 48 connections should be available) because of the following limitation: each connection involving a tributary line reduces by one unit the amount of available pass-through connections and vice-versa.

TributariesTributariesTributariesTributaries

Radio side B

1

16

1111

16

1 1632

Radio side A

Tributaries

Radio side B

1

32

1

32

1 32

Radio side A



4.3. Preservation of the cross-connection matrix

This functionality simplifies the configuration of the NE when changing from one system type to another. In the following table the behavior of the cross-connection matrix in case of system type change (keeping the same access unit) from type A to type B and viceversa is shown:

System type A System type B Cross-connection matrix

1+0 1+1(*) preserved 1+0 2x(1+0) (*) preserved 1+0 Add/Drop Repeater (*) preserved 1+0 Ring (*) preserved 1+1 2x(1+0) reset to default 1+1 Add/Drop Repeater reset to default 1+1 Ring reset to default

2x(1+0) Add/Drop Repeater preserved

(*) When changing from system type B to system type A the NE embedded SW deletes the connections involving Base Band 2 side.



5. Ethernet functionalities

Ethernet functionalities are available on IDU Plug-In platform by means of a dedicated Access Card, featuring a mixed TDM and Ethernet interface: 8xE1+4xFE or 16xE1+3xFE+1xGE, and supporting L2 switching and QoS management. The selected on-air capacity (trunk port capacity), is shared between Ethernet Traffic and PDH traffic as showed in the diagram below.

The capacity reserved for Ethernet traffic is dynamically shared among the 4 LAN ports according to QoS setting. Ethernet frames transmitted towards the radio are inserted in a NxE1 channel, with N configurable between 1 and 16, with a resolution of a single E1. N synchronous E1 signals are generated by a framer, according to the configured Trunk side capacity, while a proprietary mapping of the Ethernet frames into the NxE1 channel is performed by a mapper device. On the receiving side, N E1 de-framers and a demapper retrieve the original Ethernet frame transmitted by the remote station. IDU PlugIn provides two4 Trunk Interfaces to support both (2+0) and Add-Drop configurations. A block scheme of the Data interface unit is shown in the following figure.

4 IDU PlugIn 16xE1 provides one trunk interface only

S R A L

X D

TDM

LAN port 1

LAN port 2

LAN port 3

LAN port 4

On Air Capacity

TDM

Ethernet (Trunk capacity)

On Air Capacity

TDM

LAN port 1

LAN port 2

LAN port 3

LAN port 4

Radio Capacity



Switching Block

Scheduler

LAN Ports

Trunk Ports

E1Framer/Deframer Mapper/Demapper

Cross Connect

To BB1 card

To BB2 card

TDM



Each LAN port can be individually enabled/disabled. LAN interface is auto sensing (10 or 100 Mbit/s, half or full duplex); in any case it is possible, via management software, to set half/ full-duplex or auto-sensing mode as well as 10, 100 Mbit/s capacity. Ethernet frames with a length up to 1536 bytes are supported by LAN ports. 5.1.1. Switching The DATA Access unit implements an Ethernet bridge that has the function of Ethernet switch and manages the access on Ethernet interface to the BB cross-connection matrix. The L2 Switching is performed among the following Ethernet ports:

Four LAN ports: input/output ports on LAN network of the traffic Ethernet frames Trunk port: it is the input/output port of the Ethernet traffic towards the radio link.

Each LAN port can be enabled/disabled and configured by the user, while the Trunk port is always enabled. Each LAN port provides the following settings:

Interface enable/disable Flow Control enable/disable VLAN Tagging enabled/disable: if enabled Tag removal is applied (Trunk > LAN) and the

following shall be configured:

o VLAN ID o User priority o Tagging type: Overwrite, Double VLAN tagging (LAN > Trunk)

The switching can be performed on the basis of the MAC Address or the VLAN ID. The switching functionalities are subdivided in Filtering the Ethernet frames and Forwarding them among the available ports. 5.1.2. Filtering Filtering is performed according to the source MAC address of the incoming packets. Source MAC addresses received from LAN Ports are stored, along with the corresponding port the frame was received from (LAN and Trunk), in a data-base (MAC DB) which is continuously updated (Auto-learning mode). Each entry is stored within a configurable aging-time. Frames received from a port are discarded if the destination MAC address matches one of the MAC addresses contained in the data-base and the input port is equal to the one contained in the data-base. Also frames received from or sent to a disabled port are discarded. In case of VLAN-based switching, filtering rules are based on VLAN ID, too (see following section). 5.1.3. Forwarding All filtered frames are forwarded among the ports according to the selected forwarding mode: Fully connected LAN ports:



Each frame in input is routed only on the basis of the destination MAC address. The LAN ports are fully interconnected; this causes that the frame in input from a LAN port can be sent to any other port (LAN and Trunk), without any restriction. An uplink frame (frame in input from a LAN port): - is sent to only one LAN port if the destination MAC address is stored in the MAC DB and the corresponding port is a LAN port (LAN and Trunk), different from that in input -is sent both to the Trunk port and to all the other enabled LAN ports if the destination MAC address is unknown. A downlink frame (frame in input from the Trunk port): - is sent to only one LAN port if the destination MAC address is stored in the MAC DB and the corresponding port is a LAN port - is sent to all the enabled LAN ports in the other cases. Isolated LAN ports The LAN ports are isolated; this causes that the frames in input from a LAN port can be sent only to the Trunk port (they cannot be sent to another LAN port). An uplink frame (frame in input from a LAN port): - is sent to the Trunk port in all cases. A downlink frame (frame in input from the Trunk port): - is sent to only one LAN port if the destination MAC address is stored in the MAC DB and the corresponding port is a LAN port - is sent to all the enabled LAN ports in the other cases. Selective VLAN forwarding In each port only the passage of the frames containing a VLAN tag with the value of VLAN ID included in the list of VLAN ID associated to the port is allowed. The user can configure up to 64 different VLAN IDs, specifying the LAN port associated to each VLAN ID. All the configured VLAN IDs are always automatically associated to the Trunk port. Each frame in input from a port is discarded: - if it satisfies the filtering rules - if it does not contain a VLAN tag - if it contains a VLAN tag that is not included in the list of the VLAN tags associated to the input port - if the destination MAC address is stored in the MAC DB and the corresponding port is not included within the ports associated to the VLAN ID contained in the frame. Each received frame containing a VLAN ID associated to the input port is sent: - to only one of the other ports associated to the VLAN ID contained in the frame, if the destination MAC address is stored in the MAC DB and the corresponding port is included within the ports associated to the VLAN ID contained in the frame - to all the other ports associated to the VLAN ID contained in the frame, if the destination MAC address is unknown.



Uplink VLAN ID tagging and Replacing To each LAN port is associated only a unique VLAN ID, which can be configured by the user; it is possible to associate the same VLAN ID to more LAN ports. The frames in input from a port are managed in the following way: - if the frame contains a VLAN tag, there is the replacement of the VLAN ID contained in the frame with the VLAN ID associated to the input port - if the frame does not contain a VLAN tag, there is the insertion, into the frame, of a VLAN ID equal to that associated to the input port. Frames entering the switch from the Trunk port contain a VLAN tag otherwise they are discarded. Frames are internally forwarded according to the same rules explained for the selective VLAN forwarding mode. VLAN tag is removed from Ethernet frames exiting from LAN ports, whereas frames exiting from Trunk port keep their VLAN tag. 5.1.4. Scheduling QoS management is provided by Scheduling Ethernet frames in upstream direction (from User side to Radio side) used to transmit data frames with different priority on the radio channel, according to one of the following criteria or possibly a combination of them:

first arrived first served (no priority);

LAN port;

VLAN Identifier

IEEE 802.1p (3 bit VLAN priority field)

IPv4 (ToS or Diff-Serv)

IPv6 (Traffic Class)

The selected criterion is used to accommodate the frame in the related queue. The relationship between queue and priority parameters value is SW configurable by the user. In the scheduler, up to 4 different queues are available, according to the selected criteria and the enabled options.

Selection of the frame to be transmitted from the different queues towards the radio is done according to a fixed priority scheme or using a WFQ algorithm with fixed weights.

F I L T E R I N G

F O R W A R D I N G

Queue 1

Queue 2

Queue 3

Queue 4

SCHEDULER



If Fixed priority is selected, frames with higher priority are always transmitted first. WFQ allows to share the channel bandwidth among the four different priority levels. The four weights are fixed and respectively equal to 8, 4, 2 and 1.



6. Dynamic Modulation

IDU PlugIn provides Dynamic Modulation feature: it is supported by 16xE1 Access and Baseband 16xE1 boards with ODU HD/HP and HDe. This feature can be enabled via SW configuration on already installed SRAL XD without HW modification.

Dynamic modulation is managed by (1+0) and (1+1) Hot-standby system types.

6.1. Basic behaviour

Target of Dynamic modulation is to vary signal modulation and transmission power according to the received signal strength, which is determined by path loss, interference, etc.

More efficient modulations can be used during good weather conditions, doubling system capacity, while lower modulation schemes can be used during rain fading conditions, thus preserving high quality traffic (e.g. voice).

14 MHz

(8xE1)

4 - QAM

14 MHz

(16xE1)

16 -

4 -

16 TCM

Voice

Data Data

Voice

Data

Voice

Data

Voice

Figure 1: Dynamic modulation behaviour

When dynamic modulation is enabled, two different working modes (WM in the following) are defined:

Enhanced mode: it corresponds to NE nominal configuration and it is used during normal propagation conditions, allowing a double system capacity to be transmitted compared to the other working mode. This working mode is associated to 16-TCM modulation type (high density).

Normal mode: this mode is used when a fading phenomena or interference happens. It allows increasing system gain and system availability. This working mode is associated to 4-QAM modulation type (normal density).

Using dynamic modulation, system changes automatically between 16-TCM and 4-QAM modulation formats. Switch between WM is non hitless.



6.2. Switch-over criteria

S/N measurement is the main criterion to switch working mode. It measures the signal degradation due to different propagation conditions. Other conditions cause a Working Mode change, such as the occurrence of alarms in the Rx chain (demodulator alarm), or the state of the remote NE (each IDU controller transmits to the remote IDU controller a piece of information relevant to the status of the NE; this information is updated every 40 ms). Each ODU independently checks the condition to require a working mode change (from 16- TCM to 4-QAM) as well as the availability to use a more efficient working mode (from 4-QAM to 16-TCM), then it transmits its request/availability to the NE controller (IDU controller). Each NE decides what to do (change Working Mode or maintain the present one) according to the request/availability state(s) of its own ODU(s) and to the information received from the remote IDU controller, as well as according to local settings.

6.3. S/N measurement

Two different thresholds are defined to switch between working modes:

Threshold 1: is used as S/N threshold to switch from Enhanced to Normal WM. When system works in Enhanced mode, if measured S/N value is lower than Threshold 1, a switch-over request to Normal WM is forwarded from ODU controller to IDU controller. Threshold 1 is defined as:

Threshold 1 (Enhanced to Normal) = 16TCM_Threshold

Where 16TCM_Threshold corresponds to the S/N value which provides an estimate BER=10-9 when system works in Enhanced WM (16 dB default).

Switch from 16 - QAM to 4 - QAM

Switch from 4 - QAM to 16 - QAM

Enhanced WM Normal WM Enhanced WM

(S/N)

Threshold 1 (Enhanced to Normal WM)

Threshold 2 (Normal to Enhanced WM)

Time



Threshold 2: is used as threshold to switch from Normal to Enhanced WM. When system works in Normal mode, if measured S/N is higher than Threshold 2, a switch-over request to Enhanced WM is forwarded from ODU controller to IDU controller. Threshold 2 is defined as:

Threshold 2 (Normal to Enhanced) = Threshold 1 + Hysteresis + TX power

Threshold 1 is the threshold associated to change from Enhanced to Normal WM.

Hysteresis is a configurable value (default 2 dB, allowed range is 15 dB) introduced between Thresholds 1 and Threshold 2 to avoid oscillations between Working Modes.

TX power is managed automatically by the system and it contains the difference between the maximum TX powers in Normal WM compared to Enhanced WM.

6.4. Working mode change criteria When dynamic modulation is enabled, system starts in Enhanced WM; in this phase it ignores all requests to use Normal WM for a fixed interval in order to avoid algorithm instability. Then, if local S/N is lower than Threshold1 or if there are stable alarms in the Rx chain the local system swaps to Normal WM; the remote NE reacts by switching to Normal WM, too. In case of local controller failure, change of modulation is inhibited on both local and remote side of the radio link. In (1+1) HSby system local TX/RX HW failure causes automatic HSby switch; the remote ODUs do not request to IDU controller to switch to 4-QAM because they recognize an RF loss period longer than the one due to a remote WM change, so the radio hop keeps on working using 16-TCM modulation. As soon as the NE enters the Normal WM, it ignores any request to use Enhanced WM for a given time interval. When this time is elapsed, local controller starts managing current states. If no alarms are present and dynamic modulation is enabled, each NE independently switches modulation format when local ODU gives its availability to support 16-TCM and the remote NE is signalling its ready to support 16-TCM too (that is when both NEs detect local S/N higher than the given threshold 2). As soon as both the conditions are simultaneously verified, the NE controller waits for a fixed time interval (user selectable) and then it changes the modulation format from 4-QAM to 16-TCM. No switching is performed if the remote NE controller is declared failed by the local NE controller. In (1+1) HS-by system type the NE takes into account 16-TCM availability indication transmitted by the ODU supporting the signal transmitted to the Access unit.



6.5. Working mode parameters

Using 16xE1 Access and Baseband boards, the payload types and associated modulation types involved in dynamic modulation procedure are shown in Table1.

Enhanced WM Normal WM

Channel size

Modulation type

Radio Capacity

Modulation type

Radio Capacity

14 MHz 16xE1 (14 MHz) 8xE1

7 MHz 16-TCM

8xE1 (7 MHz) 4-QAM

4xE1

User needs to activate a license to enable dynamic modulation and 8xE1 capacity is licensed at least (16xE1 license is also needed if this Enhanced WM capacity needs to be configured).



7. Management

7.1. DCN

In the SRAL XD product line, system concept and embedded software architecture have been designed to permit a user-friendly and effective local and remote terminals management. TCP/IP Communication protocols and standard physical interfaces have been adopted to simplify and speed up DCN implementation and to allow an easy integration in 3rd party Management Systems.

The management information are stored and processed by the NE controller and made available externally to the network operator through standard interfaces: Q LAN 10/100BaseT: The Q LAN interface carries the Transmission Network Management (TNM) information used by Operation and Maintenance Center (OMC) to manage the network nodes. The Q channel can operate with auto-negotiation both half duplex and full duplex, both 10 BaseT or 100 BaseT. V-LAN 10BaseT interface5: The V LAN is made available for the interconnection among the equipment Controllers of several systems located in the same site

5 Not available on Outdoor Access Unit

OMC

SRAL XD

DCN



The V LAN interface together with the Q LAN makes available the connection, throughout Tx/Rx crossover cables, among more equipment Controllers of the same site and the OMC without applying external elements.

D-ext Channel V.11 contra-directional6: Allows to carry the management information through a data network. The standard PPP over HDLC is the protocol of this channel for the interconnection with third part equipment (routers). The D-ext channel also allows the connection with SRA L equipped with V.11 card.

6 6 Not available on Outdoor Access Unit

QLAN VLAN

QLAN VLAN

QLAN VLAN

VLAN

VLAN

VLAN

HUB



The interface is fully routed and routing protocol announcements are supported (dynamic routing and associated announcements can be switched on or off by NMS for this interface). User Channel V.11 co/contra-directional7: The User channel is a general purpose data channel, which is made available for user-defined applications. The equipment performs the point-to-point transport of this channel, and is completely transparent to channels content. The User and Dext Channel are provided by means of the same connector. The functionality actually implemented has to be configured by SW setting. D-Embedded Channel8 It is a 64kbps channel framed in a single time slot inside one E1 stream. The time slot and the specific E1 stream9 can be set via software. D-Embedded channel is used to carry the management information between two NEs, that are not connected by means of any other transmission media.

V bus Channel

7 Not available on Outdoor Access Unit

8 In case of IDU PI 16xE1 in 2x(1+0) or Add/Drop system types, two D-emb channels are available. 9 In case of IDU PI 16xE1, only tributaries 14 Radio-side can be used for D-emb channel transport; in case of IDU 32xE1 any

tributary radio-side can be used for D-emb channel transport.

NE

PSTN

NE NE

D-Embedded D-Embedded

R Channel

DATA NETWORK

NE

ROUTER ROUTER

LAN

ROUTER WITH V.11 INTERFACE



The V bus interface is available on IDU Plug-in controller in order to interconnect SRA L equipment located in the same station. The V bus channel utilizes a proprietary protocol. Up to 32 independent SRA L units placed in the same site can be connected to the V-bus 120 cable. R Channel R channel is a 64 kbps out of band channel accessible only via the controller, that carries management IP packets over the radio interface. The interface is fully routed and routing announcements are supported (dynamic routing and associated announcements can be switched on or off by NMS for this interface). Standard PPP protocols over HDLC Local Craft Terminal Interface: A 38,4 kbps synchronous data channel is available to connect a PC to the NE for local management adopting a standard PPP protocol. A relevant software package, LinkViewer, is provided for local management and maintenance. This interface can be also used for DCN purpose.

V LAN Q LAN

RS 232

Dext User Vbus

ODU

R CHANNEL

User CHANNEL

Payload

Traffic

DEmbedded



7 Network Management System

A continuous supervision of the whole SRAL XD network is available, with automatic alarm reporting and complete network block representation, using the NetViewer software package. The NetViewer system platform comprises standard PCs under Microsoft Windows NT/ Windows 2000 for reduced costs and increased simplicity. The user interface, developed with the look and feel of standard Windows applications, is designed for intuitive operation.

In order to increase efficiency and reduce staff training time, NetViewer supports different interfaces to the Data Communication Networks (DCN) giving a wide level of freedom for creating networks of different sizes. For controlling DCN, often designed with devices based on SNMP protocol such as routers and interface converters, the SNMP device management performed by NetViewer allows the complete monitoring of all the Network Elements included in the network. NetViewer supplies the HTTP interface enabling the user to access it via Internet and Intranet using browsers as Netscape and Microsoft Explorer for supervisioning the SRAL XD networks. The tunnelling of IP over OSI allows a SRAL XD network to be connected to the TMN of a SDH network This integration gives the big advantage of having an integrated solution for the management of a mixed PDH-SDH network. This advantage is further highlighted by the fact that the Siemens SDH operating system can also perform the network control layer facilities. Siemens Management System portfolio also comprises TNMS Core (Siemens SDH TMN platform) and Radio Commander (Siemens Mobile TMN platform). Also devices of different vendors based on SNMP protocol can be managed by NetViewer.



Local Management and Maintenance of the SRAL XD is performed by LinkViewer, the Element Manager running on LCT.

7.1 Security

7.1.1 Access Security

The access to the equipment, by means of LCT/NMS, is allowed to authorized users on the basis of three different user classes:

Read Only: Read/Write: Admin

The configuration of the Security (enabling status and password) is stored into the equipment memory.

7.1.1.1 Priority in Read/Write Access It is possible to select the priority in write access of an LCT/NMS connecting to the NE with respect to the LCT/NMS already connected to the NE. Since the NE supports only one user at a time with read/write capability, the Admin or Read/write user that was previously connected is disconnected by the NE itself, unless it changes its user level to Read/only after a warning transmitted by the NE10. Aim of this feature is to allow a connection with read/write properties at any time, in order to perform an urgent maintenance operation on the appliance without the need to request to the main NMS, usually connected with read/write capability, a manual change of its access level.

7.1.2 Protocol ports security

The ports relevant to debugging IP-based protocols (Telnet, TNMP, HTTP, FTP) can be enabled/disabled by the operator.

10 This feature is supported by Netviewer 7.0 onwards.

INTRANET

INTERNET



7.1.3 Same Admin password for FTP/TELNET/TNMP

Password of both FTP and Telnet Admin user is the same as TNMP Admin user class password. It isnt possible to directly modify the FTP and/or Telnet Admin password, but any change in the TNMP Admin password affect s both the FTP and Telnet Admin password.

7.1.4 SSH on FTP / Telnet session

NE embedded SW includes an SSH server running SSH-2 protocol version and supporting file transfer and remote command execution. SSH functionalities (enabled/ disabled via TNMP configuration) allow user authentication and traffic encryption between two hosts, thus improving the security of communication. User authentication/ authorization is password-based (the password is linked to TNMP Admin password). File transfer is carried via sftp protocol (same users and passwords used by FTP are supported), whereas remote command execution is carried via ssh: this sw tool is similar to TELNET but commands, passwords and data are encrypted.

7.1.5 Accounting log

The Accounting log functionality allows storing in the NE (non volatile memory) a list of up to 120 records of relevant log actions (login or logout) performed by users. When the reserved memory is full, a new log action will cause the oldest one to be deleted (overwritten by the new one). Each record will include the following information fields:

IP address of the user; user class (Admin, Read Write or Read Only); log action; date and time of the log action.

The accounting Log file is available uploading a file via FTP.

7.2 Configuration management: The Status and Config function allows checking the operating status of the equipment and configuring, according to the available hardware and license, all the system, operating and network parameters.

Equipment: System capacity, Modulation Format, Operating channel, RF channel plan, RF output power, BB and RF switches, Link ID

Software: Management of the equipment software Network: Link ID, System address (NMS), D-embedded Management Alarms Config: Alarm configuration Time Settings: Synchronization configuration

In case of protected configuration it is needed to set the TX/Rx channel for just one ODU, the second one will be aligned automatically by the SW command RF Channel Self Alignment



7.3 Commissioning Facilities: The SRAL XD provides a set of feature for support during commissioning activities in order to monitor the performance of the NE during a stated period of time and the correct working of protection switching allowing to force each available switch.

7.3.1 Long period performance monitoring recording

In order to verify the proper set up of the radio hop, Performance Monitoring data (G.826, RSPI and RPS) relative to last 192 consecutive and complete 15minutes periods are stored and can be transferred via FTP, in order to be processed by MS office SW.

Two options are available:

- Last Quarter: storing continuous and cyclical

- From Start Time: to set the beginning of data collection

7.3.2 Time switched forcing

It allows forcing the switch position for a certain period (selected by the user). The following options are available:

- Single sequence

- Periodic (for Hot Stand-by System Types): the switch is forced every n days (n=0400), in order to verify the integrity of the complete Stand-by transmission chain.

The following switchings are performed according to the System Type:

-Base Band:

Time

Start

Time PM Recording duration

(192 15 periods)

Start of current 15 period

Time

PM Recording duration (192 15 periods)

From Start Time

Last Quarters

Get results

Working

Stand By

Repetition Period



FD : selection of BB in Tx and Rx side

HSBY : selection of the active ODU in Tx side and the BB in Rx side

- Hitless Rx Switch (for FD configuration)

7.3.3 Local History Log

This feature supports the recovery of the recent history of the appliance: the Network Element controller saves in its volatile memory the last 4000 events and pseudo-events.

It is possible to retrieve both a subset of events and pseudo-events to complete a missing portion of the Network Element history (for example in case of temporary disconnection of the NE from the NMS) and the complete saved history (for example a local download from NE not connected to a network management system)

7.3.4 Measurement

The NE allows the measurement of the following parameters by means of both LCT/NMS:

Inner temperature of the ODU Inner temperature of the IDU (functionality supported by Controller Unit of IDU Plug-in11): Received power (RF RX) and transmitted power (RF TX) Statistic measures of the Ethernet traffic interface (only for DATA Access unit)

7.3.5 Performance Monitoring

The system allows the execution of the analysis and the recording on file of the performance data. Several types of performance data are available:

quality and unavailability counters, applied to the aggregated radio signal, measured in according to ITU- T G.826 recommendation

RSPI (Radio Synchronous Physical Interface) parameters, applied to each transceiver, and mainly related to the received and transmitted power

RPS (Radio Protection Switching) event counters, applied to each switching functionality Measurements periods are 15 minutes or 24 hours; besides the current periods, the NE stores the last 16 completed 15 minute periods and the last 4 completed 24 hour periods. There are 3 major measurement points:

before protection switching (one per transceiver) after protection switching (one in 1+0 and two in 2x(1+0); only one in protected 1+1 system

types)

at Radio Protection switching level (one per network element)

11 Code 634-001/74 from HW edition n8



Each measurement period is characterized by:

all the applicable measurements; a time counter for each measurement point: the actual number of seconds in the interval

(namely 900 and 86400);

a suspect interval flag for each measurement point: boolean indication of abnormal situation during measured performance.

Configuration of performance data is possible in case of login (via NMS or LCT) with read/write privileges; collected data can be displayed on a quarter of hour basis (current quarter of an hour and sixteen previous ones) or on a daily basis (current 24 hours and previous four intervals of 24 hours).

Displaying G.826 performance (Day)

Protection Switching

Radio Interface #2

Radio Interface #1

Mesurement Point After protection



Displaying G.826 performance (Quarter)

Netviewer /LCT allow recording on file of the performance data referred to quarters of hour, according to the selected System type.

7.4 Fault management: The SRAL XD equipment is provided with an alarm system, with different signaling modes (via software, LED, connector outputs), that starting from an alarm signal allows to the operator to identify quickly the failed module or function. Software Alarms are reported on LCT/NMS and are organized in different groups:

Physical TX/RX Tributary Network Station

Each board is equipped with some LEDs reporting alarms related to the board. Moreover, the IDU is equipped with an Alarms Connector carrying a number of signal lines, associated to these main functionalities:

Delivery to the outside of radio equipment of summarized alarms related to equipment status

Transparent transport 12 via radio link of up to 4 13, externally supplied, alarm lines i.e., open-door alarm, smoke alarm, switch commands, etc (input lines) It is possible selecting independently for each line the electrical condition (ground or open) corresponding to a rising of an alarm.

Delivery12 to the outside of radio equipment of the 413, externally supplied, alarm lines transported via radio link from the far-end

12 Functionality supported by IDU Plug-in and OAU 13 2 input alarm lines are supported by OAU.



7.5 Maintenance

For maintenance purpose the following loop-backs can be provided: Local loop-back

The E1 tributary signal can be looped back in the base-band unit at the E1 input interface level. This type of loop-back when activated allows testing the integrity of the circuitry related to line interface access.

Remote loop-back

Each E1 tributary stream can be looped back in the remote station, just before the E1 output interface. This t