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7/23/2019 SDR Link Budget.pdf
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SDR Link Budget
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1 SDR Equipment
Summary
This chapter mainly introduces family members of currently used SDR
equipment: BS8800, BS8900, BS8700 (B8200+R8860) and outdoor micro
BS8906 G060.
For this chapter, parameters of several main RF units need to be
understood.
1.1 Introduction to Family Members of SDR Equipment
At present, the family members of SDR equipment mainly are: indoor
macro BS8800, outdoor macro BS8900, distributed BS8700 (B8200+R8860)
and outdoor micro BS8906 G060.
All above mentioned BTSs have the same BBUs (base band unit), and
they all adopt baseband pool unit B8200; for RF part,
RU02/RU02A/RU60/RSU60 can be used both on BS8800 and BS8900. Inaddition, the outdoor micro BTS can only adopt RSU70, and the RF unit of
distributed BTS can only adopt R8860.
1.1.1 BS8800
BS8800 is a new generation indoor dual-mode macro BTS which adopts
multi-carrier and SDR technology. ZXSDR BS8800 GU360 provides completely
new solution for hybrid networking of GSM/UNTS and network evolution. It can
be widely applied under such environments as dense urban areas, urban areas,
suburban areas, remote suburban areas and highway.
BS8800 is divided into two parts: BBU & RF. The BBU refers to the base
band pool B8200 build in the rack. RF unit consists of dual-density carrier
RU02 and RU02A as well as multi-carrier technology based RU60 and RSU60.
Those modules can be both used on BS8800 and BS8900. BBU and RF unit
will be further introduced in following chapters.
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In addition, the fan module and power distribution module are also placed
in the rack, wherein, the power distribution module is a passive module playing
the role of power switch. The sketch map of BS8800 rack is as follows:
Figure 1-1 Structure Chart for BS8800 Rack
The sketch map for various modules and antenna connection in the rack is
as follows:
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Figure 1-2 Sketch Map for Wiring in BS8800 Rack
For BS8800, each RF module is directly connected to FS board of BBU via
optical fiber.
BS880 supports GPS synchronization. When adopting GPS signal for
synchronization, GPS processing module is built on CC board with GPS
antenna interface provided on the board. GSP antenna is placed outside the
cabinet and connected to CC board of BBU via feeder cable.
RF unit and BTS antenna are also connected via feeder cable.
1.1.2 BS8900
BS8900 is a new generation outdoor multimode macro BTS which adopts
multi-carrier and SDR technology. ZXSDR BS8900 GU360 provides completely
new solution for hybrid networking of GSM/UNTS and network evolution. It can
be widely applied under such environments as dense urban areas, urban areas,
suburban areas, remote suburban areas and highway.
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BS8800 also adopts the same RF and base band separation structure with
BS8800. And its BBU and RF units all can be used on BS8800.
BS8900 is composed by outdoor RF cabinet, site supporting cabinet and
battery cabinet. The following figure shows several composition ways of
BS8900 rack.
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Figure 1-3 Typical Configuration of BS8900: BC8910+RC8911
Figure 1-4 Typical Configuration of BS8900: BC8910+RC8911+RC8931
Figure 1-5 Side-by-side Cabinet of BS8900: BC8910+RC8910+PC8910
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1.1.3 BS8700 (B8200+R8860)
BS8700 composed by base band unit B8200 and RF unit R8860 can
support remote RF. A single site can support 6 cells at maximum, and can
support networking in chain topology, star topology and hybrid topology. For
chain networking, an optical fiber can support 4 cascade tiles at maximum, and
the maximum distance between BBU and the last RRU is 40km.
Figure 1-6 Sketch Map for Chain Networking of B8200+R8860 Distributed BTS
1.1.4 BS8906 G060
BS8906 features small volume, light weight, low cost and flexible
configuration, and is mainly used in outdoor micro BTS scenario, indoor micro
BTS scenario and indoor distribution. It is suitable for outdoor small capacity
application, non-equipment room environment, hot spot area coverage, blind
spot area (e.g.: tunnel) coverage and margin network application.
BS8900 is designed with RF and base band separation structure. Its base
band module can be in common use with that of indoor macro BS8800, and the
RF module adopted is generally RSU60. Single cabinet of BS8906 can support
6 carriers at maximum, and the site capacity can also be extended via
connecting with additional R8860.
BS8906 is convenient for installation, and occupies little area. It can be
installed in multiple ways including pole-mounting, wall-mounting and
floor-fixation manner (via standing bracket).
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Figure 1-7 Appearance of BS8906
1.2 Introduction to SDR BBU (Base Band Unit)
The BBU of SDR base station is B8200, and B8200 GU360 is a G/U
supported BBU.
1.2.1 Introduction to Structure and Board Functions of B8200
BBU (Base Band Unit) consists of control and clock board (CC), fabric
switch board (FS), base band processing board (UBPG for GSM, BPC for
UMTS), site alarm board (SA), site alarm extension board (SE, optional),
Network Interface Board for STM-1 (NIS, optional), power module (PM) and fan
module (FAM).
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Figure 1-8 Sketch Map for BBU (B8200)
Board Name Board Function Introduction
CC Control & Clock Board
FS Fabric Switch Board
UBPG Universal Baseband Processing board for GSM
BPC Baseband Processing Board for UMTS
SA Site Alarm Board
SE Site Alarm Extension Board
NIS Network Interface of STM-1
PM Power ModuleFAM FAN Module
Table 1-1 Main Boards in BBU of ZXSDR BS8800
Caution:
For two network standards GSM and WCDMA, different baseband boards need
to be configured which are respectively UBPG and BPC. A UBPG can process
12-channel baseband signals. When only a piece of FS board is configured, aB8200 can be configured with 5 pieces of baseband boards with 60-channel
baseband signals supported at maximum.
1.2.2 Capacity Indexes of B8200
TRXs supported at maximum for GSM: 60 TRX (single UBPG can support
12 TRXs, and totally 5 boards can be configured)
CSs supported at maximum for UMTS: 15 CS (single BPC board can
support 3 CS, and totally 5 boards can be configured).
1.3 Introduction to Main Modules of SDR RF Unit
The RF unit of SDR BTS consists of five RF modules, which respectively
are RU02, RU02A, RU40, RU60, RSU60 and R8860. Wherein, RU40 is a
UMTS single-mode multi-carrier RF module which only works in 2100M
frequency band; RU02 and RU02A are all GSM single-mode dual-density
carriers, which can work under 900/1800M frequency band. RU02A can not be
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used for networking individually; RU60, R8860 and RSU60 are all based on
multi-mode multi-density carrier technology, and can work under 900/1800
frequency band with G/U dual modes supported. R886 is a MCPA-based
remote radio unit (RRU), and can form distributed BTS together with B8200.
1.3.1 RU40 (Only Applicable to UMTS 2100M)
1.3.1.1 Outward Appearance
RU40 is a single mode multi-carrier RF module only working under
2100MHz. It consists of multi-carrier power amplification module, transmission
module and duplex filter LNA, and can provide two-channel antenna interfaces
and two pairs of CPRI interfaces.
Figure 1-9 Sketch Map for Outward Appearance of RU40
1.3.1.2 Output Power
RU40 module can support 4 carriers at maximum, and the total cabinet-top
output power is 60W. For UMTS, the cabinet-top output power must be
ensured to be 20W per carrier, and a piece of RU40 supports 3 carriers.
RU40 is a multi-carrier RU module, it currently follows the principle ofequal power division for each carrier, and the total cabinet-top power is kept at
60W. For example, if 3 carriers are configured, the cabinet-top output power of
each carrier is 20W.
RU40 Power
Total PA Output Power (W) 85
Total Cabinet-top Output
Power (W)
60
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Table 1-2 Total Output Power of RU40
1.3.1.3 Working Frequency BandItem Index
Working Frequency Band UMTS: 2100 MHz
Table 1-3 Working Frequency Band of RU40
1.3.1.4 Sensitivity
Item Index
Sensitivity of Receiver -126.5dBm@UMTS Single Antenna
Reception
-129.2dBm@UMTS Dual Antenna
Reception
Table 1-4 Sensitivity of RU40 Receiver
1.3.2 RU60 (GSM/UMTS)
1.3.2.1 Outward Appearance
RU60 is a multi-carrier RF module, and it can work under GSM singlemode, UMTS single mode or GSM/UMTS hybrid mode via software setting.
Main interfaces on RU60 panel include antenna feeder interface, extended
RX interface as well as baseband fiber interface. Totally two antenna feeder
interfaces are available, one is RX/TX dual diplex interface, and the other is RX
interface. In addition, the panel is also equipped with two RX extended
interfaces, respectively for input and output of diversity reception signal. There
are also two fiber interfaces on the panel, one for connecting with the BBU, and
the other for cascading with other RU modules.
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Figure 1-10 Sketch Map for Outward Appearance of RU60
1.3.2.2 Output Power
RU60 can be used for GSM single mode networking, UMTS single mode
networking or GU hybrid networking. The total PA output power is 83W
(GMSK)/60W (8PSK)/83W(UMTS); the total cabinet-top output power is 60W(GMSK)/40W (8PSK)/60W (UMTS).
Mode PA Output Power Cabinet-top Output Power
GSM GMSK 83W/ 8PSK 60W GMSK 60W/ 8PSK 40W
UMT
S83W 60W
Table 1-5 Total Output Power of RU60
When RU60 is used in GSM network, it can be configured with one to 6
TRXs via software setting. Under GMSK modulating mode, the total
cabinet-top output power is 60W; under 8-PSK modulating scheme, the
total cabinet-top output power is 40W.
The R8.2 and latter versions all can support independent configuration of
power for each carrier with following conditions satisfied:
1. All GSM TRXs configured in the same RF module have the same output
power.
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2. For power level adjustment, the adjustment granularity of each TRX must
be the same.
3. GSM TRX quantity power of each TRX + UMTS carrier power
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Table 1-8 Working Frequency Band of RU60
Caution:
At present, the working bandwidth of RU60 has a restriction of 10MHz.
Therefore, the frequency points configured on the same RU60 should be within
a range of 5MHz of the central frequency points.
1.3.2.4 Sensitivity
Item Indexes
Sensitivity of the Receiver -112 dBm@GSM single antenna
reception
-126.5dBm@UMTS single antenna
reception
-129.2dBm@UMTS dual antenna
reception
Table 1-9 Reception Sensitivity of RU60
1.3.2.5 Supporting Coverage Enhancement Technology
Supporting DDT/FWDR/IRC.
1.3.2.6 Supporting Frequency Hopping
Supporting baseband frequency hopping/RF frequency hopping.
1.3.3 RSU60 (GSM/UMTS)
1.3.3.1 Outward Appearance
RSU60 is a multi-carrier RF module, and it can work under GSM single
mode, UMTS single mode or GSM/UMTS hybrid mode via software setting.
Main interfaces on RSU60 panel include antenna feeder interface,
extended RX interface as well as baseband fiber interface. Totally two antenna
feeder interfaces are available, one is RX/TX dual diplex interface, and the
other is RX interface. In addition, the panel is also equipped with two RX
extended interfaces, respectively for input and output of diversity reception
signals. There are also two fiber interfaces on the panel, one for connecting
with the BBU, and the other for cascading with other RU modules.
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Figure 1-11 Sketch Map for Outward Appearance of RSU60
1.3.3.2 Output Power
RSU60 can support GSM/UMTS dual mode. The total cabinet-top output
power is 80W (GMSK)/50W (8PSK).
Mode Cabinet-top Output Power
GSM GMSK 80W/ 8PSK 50W
Table 1-10 Total Output Power of RSU60
When RU60 is used in GSM network, it can be configured with one to 6
TRXs via software setting. Under GMSK modulating scheme, the total
cabinet-top output power is 80W; under 8-PSK modulating scheme, the
total cabinet-top output power is 50W.
The R8.2 and latter versions all can support independent configuration of
power for each carrier with following conditions satisfied:
1. All GSM TRXs configured in the same RF module have the same output
power.
2. For power level adjustment, the adjustment granularity of each TRX must
be the same.
3. GSM TRX quantity power of each TRX + UMTS carrier power
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RSU60 80W
GSM: 9 levels
(10W/12W/15W/20W/25W/30W/40W/60W/80W)
UMTS: 20W/30W/40W
Table 1-11 Carrier Power Allocation of RSU60 under R8.2
Caution:
For GSM network, the cabinet-top output power under 8PSK modulation
scheme is about 2dB lower than that under GMSK modulation scheme.
1.3.3.3 Working Frequency Band
Item Indexes
Working Frequency Band GSM: EGSM/900/1800MHz
Table 1-12 Working Frequency Band of RSU60
Caution:
At present, the working bandwidth of RSU60 has a restriction of 15MHz.
Therefore, the frequency points configured on the same RSU60 should be
within a range of 7.5MHz of the central frequency points.
1.3.3.4 Sensitivity
Item Indexes
Receiver Sensitivity -112 dBm@GSM single antenna
reception
Table 1-13 Reception Sensitivity of RSU60
1.3.3.5 Supporting Coverage Enhancement Technology
Supporting DDT/FWDR/IRC.
1.3.3.6 Supporting Frequency Hopping
Supporting baseband frequency hopping/RF frequency hopping.
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2 Link Budget for Typical SDR Sites
Summary
This chapter mainly introduces cabinet-top power and other parameters of
typical SZDR sites, the key point is to highlight the link budget differences with
traditional sites or specially noted parameters, and examples for link budget will
also be demonstrated.
To sum up, the link budget of SDR sites has three main differences in
comparison with that of traditional site:
Cabinet-top output power calculation method;
Consideration for feeder loss when RRU is installed close to the
antenna/platform under distributed networking mode;
Extra uplink/downlink gains under OTSR networking mode;
2.1 RU60
RU60 is a G/U dual mode multi-density RF unit which can support GSM
single frequency, UMTS single frequency, GSM dual frequency and G/U dual
mode networking. The link budget difference between RU60 and traditional
BTS is the method for calculating cabinet- top power. The traditional 7/8, 5/4
or 1- 5/8 cables are taken as main feeder cables, and the feeder cable
calculation method is the same with that of traditional BTS.
2.1.1 Typical Sites Configuration
2.1.1.1 GSM Single Frequency Band Networking
2.1.1.1.1 S1~6
When a single sector has less than 6 TRXs or 6TRXs, each cell should be
configured with a RU60 and a pair of duplex & dual polarization antennas. The
number of BBU should be determined based on total number of physical
carriers in GSM network. And each UBPG board can support 12TRXs at
maximum.
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The total cabinet-top output power of each cell is 60W, and the power is
equally allocated to each TRX. For cabinet-top output power under different
carrier configurations of RU60, please refer to section Erreur ! Source du
renvoi introuvable. .
Select RU60-900 for 900MHz GSM independent networking, and select
RU60-1800 for 1800MHz GSM independent networking.
The antenna connection of RU60 is as shown in following figure:
Figure 2-1 1 to 6 GSM Carriers Configuration for RU60
2.1.1.1.2 S7~12
When one sector has more than 6 TRXs (7 to 12 TRXs/cell), each cellshould be configured with two RU60 modules but only one duplex &
dual-polarized antenna is needed. Two RU60 are bridged via extended RX
interface and no external combiner is needed. The configuration of BBU should
be determined based on total number of physical carriers in GSM network. And
each UBPG board can support 12TRXs at maximum.
For cabinet-top output power under different carrier configurations of RU60,
please refer to section Erreur ! Source du renvoi introuvable. .
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For example, if the cell is configured with 8TRXs, two RU60 are used with
4 carriers configured on each RU60, and the cabinet-top output power of each
carrier is 15W.
Select RU60-900 for 900MHz GSM independent networking, and select
RU60-1800 for 1800MHz GSM independent networking.
The specific antenna connection is as follows:
Figure 2-2 7 to 12 Carriers Configuration for RU60
2.1.1.1.3 S1~6 (DDT+FWDR)
When DDT and FWDR are adopted, each cell must be configured with two
RU60s, and two duplex & dual-polarized antennas are also needed. As two
RU6s transmit the same signals, the TRXs are logically thought as the same
TRX. At this time, the baseband board quantity needs to be calculated
according to the quantity of physical carriers, for example, for S4/4/4 under
DDT+FWDR mode, the quantity of baseband boards (two UBPG boards)
configured should be calculated as per 24TRXs.
For cabinet-top output power under different carrier configurations of RU60,
please refer to section Erreur ! Source du renvoi introuvable. .
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Select RU60-900 for 900MHz GSM independent networking, and select
RU60-1800 for 1800MHz GSM independent networking.
Antenna feeder connection under such mode is as shown in following
figure:
Figure 2-3 1 to 6 Carriers (DDT+FWDR) Configuration for RU60
2.1.1.2 UMTS Single Frequency Band Networking
2.1.1.2.1 1~3 C1S
For UMTS single frequency band networking, one RU60 can support 4
carriers/sectors at maximum. To guarantee the cabinet-top output of 20W for
each carrier, each RU60 can support 3 carriers/sectors at maximum. Under
3C1S conditions, only a pair of duplex & dual-polarized antennas are needed,
the BBU can be configured as per quantity of UMTS sectors, and each BPC
board can support 3 CS at maximum.
The total cabinet-top output power of each RU60 is 60W, and the output
power of each carrier should be guaranteed to be no less than 20W.
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Figure 2-4 1 to 3 Carriers Configuration in Each UMTS Sector for RU60
2.1.1.2.2 4~6 C1S
For UMTS single frequency band networking, to guarantee a cabinet-top
output power of 20W for each carrier, each RU60 can support 3
carriers/sectors at maximum. If each sector is configured with 4 to 6 carriers,
only a pair of duplex & dual-polarized antennas are needed, two RU60s are
bridged via extended RX interface, and no external combiner is needed. TheBBU should be configured as per quantity of UMTS sector, and each BPC
board can support 3 CS at maximum.
The total cabinet-top output power of each RU60 is 60W, and the power of
each carrier should be guaranteed to be no less than 20W.
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Figure 2-5 4 to 6 Carriers Configuration in Each UMTS Sector for RU60
2.1.1.3 GSM900/1800 Dual Frequency Band NetworkingThe configuration principle for dual frequency networking is the same with
that of single frequency networking and the differences is that each RU60
module can only support a frequency band; therefore, dual-frequency band cell
needs two RU modules at least, for example, for GSM900 S2+GSM1800 S2,
each cell needs to be configured with a RU60-900 and a RU60-1800. The
baseband board quantity is determined by total TRX quantity of dual frequency
band.
Please see section Erreur ! Source du renvoi introuvable. for
calculation of cabinet-top powers under GSM900/1800.
If the antenna feeder configuration should be jointly shared, an external
bandwidth combiner is also needed.
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Figure 2-6 GSM900/1800 Dual Frequency Band Networking for RU60 (Antenna Unshared)
2.1.1.4 GSM/UMTS Dual Mode Networking2.1.1.4.1 G/U CO-Frequency Band Configuration
For G/U co-frequency band, the RU60 module can be jointly shared, S2
(GSM) + S2 (UMTS) or S4 (GSM) + S1 (UMTS) are supported, and the
antenna feeder and antenna are all shared. UBPG and BPC should be
configured as per respective carrier quantities of GSM and UMTS network.
Please see section Erreur ! Source du renvoi introuvable. for
cabinet-top power of each carrier under G/U hybrid mode.
Figure 2-7 Configuring S2 (G) + S2 (U) or S4 (G) + S1 (U) by RU60 under G/U Co-Frequency Band Conditions
As shown in the figure, the cabinet-top power of GSM carrier is 10W and
the cabinet-top power of UMTS carrier is 20W.
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Figure 2-8 Configuring S8 (G) + S2 (U) or S4 (G) + S4 (U) by RU60 under G/U Co-Frequency Band Conditions
As shown in above figure, the cabinet-top power of GSM carrier is 10Wand the cabinet-top power of UMTS carrier is 20W.
Figure 2-9 Configuration of the Site with Maximum Capacity by RU60 under G/U Co-Frequency Band Conditions
for BS8800
As shown in above figure, under G/U co-frequency band conditions,
BS880 adopts RU60 as RF module, which can support the configuration of
S666(G)+S333(U) or S888(G)+S222(U) at maximum. The cabinet-top power of
GSM carriers is 10W, and the cabinet-top power of UMTS carriers is 20W.
2.1.1.4.2 G/U Inter-frequency Band Configuration
Under G/U inter-frequency conditions, G/U needs to be configured with
independent RU module. For example, for GSM1800+WCDMA900,
RU60-1800 and RU60-900 should be respectively configured, and independent
feeder cable and antenna should also be used, as shown in following figure. If
broadband antenna is needed, additional external broadband combiner should
also be used.
The configuration principle of G/U baseband board is unchanged, and the
board number is still calculated as per carrier quantities of G/U.
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Figure 2-10 G/U Inter-Frequency Band Configuration for RU60
2.1.2 Link Budget Examples
Caution:
All following link budget results can only be taken as reference, and should not
be quoted in link budget of any project, as the estimation result is of no
usability and is not informative. Any one who quotes the estimation result
directly in any specific project will undertake corresponding result.
Hypothesis:
Following four sections introduce some link budget examples. For G/U hybrid
mode and G mode, only link budget for GSM network is introduced. And the
link budgets are all under conditions of 900M frequency band, common urban
area (MU), adopting Okumura-Hata module, antenna mounting height
supposed to be 25m, and 7/8 main feeder cable.
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For GSM900/1800 dual frequency networking and G/U inter-frequency
networking, the link budget needs to be conducted respectively. Please refer to
following link budget examples.
2.1.2.1 GSM900 S2 & S3
RU60 2TRX RU60 3TRXEGSM/900M,MU EGSM/900M,MU
UpLink DownLink UpLink DownLinkTX Rank-top Output Power(dBm) 33.00 44.77 33.00 43.01DDT (dB) 0.00 0.00Total Cable Loss (dB) 2.22 2.22 2.22 2.22Feeder Loss (dB) 1.16 1.16 1.16 1.16Jumper Loss (dB) 0.56 0.56 0.56 0.56Connector Loss (dB) 0.30 0.30 0.30 0.30Lightening rod Loss (dB) 0.20 0.20 0.20 0.20TMA Insertion Loss (dB) 0.00 0.00TX Antenna Gain (dBi) 0.00 17.00 0.00 17.00EIRP (dBm) 33.00 59.55 33.00 57.79
Antenna Diversity Gain (dB) 3.00 3.00RX Sensitivity (dBm) -112.00 -102.00 -112.00 -102.00TMA Contribution to Sens. (dB) 0.00 0.00RX Antenna Gain (dBi) 17.00 0.00 17.00 0.00FWDR (dB) 0.00 0.00IRC (dB) 0.00 0.00Acceptance Level (dBm) -73.00 -73.00Log-Normal Margin (dB) 8.70 8.70Allowed Max Path Loss (dB) 125.08 123.85 125.08 122.09Uplink-Downlink (dB) 1.23 2.99Limited DL Limited DL LimitedAllowed Max Path Loss (dB) 123.85 122.09SSdesign (dBm) -64.30 -64.30SSacceptance (dBm) -73.00 -73.00BTS Antenna Height (m) 25.00 25.00
MS Antenna Height (m) 1.50 1.50 Area Coverage Probability 95% 95%Cell Radius (km) 0.90 0.80
Table 2-1 Link Budget for GSM S2 and S3 Type Sites Configuration by RU60
It can be seen from above table that when configuring GSM900 S2 and S3
type sites by RU60, only the cabinet-top output power is different, and all other
link budget parameters are the same. For S2-type site, the cabinet-top power is
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30W (44.77dBm) and for S3-type site, the cabinet-top power is 20W
(43.01dBm).
2.1.2.2 GSM900 S2 (DDT+FWDR)
RU60 2TRX(DDT+FWDR)EGSM/900M,MU
UpLink DownLinkTX Rank-top Output Power(dBm) 33.00 44.77DDT (dB) 3.00Total Cable Loss (dB) 2.22 2.22Feeder Loss (dB) 1.16 1.16Jumper Loss (dB) 0.56 0.56Connector Loss (dB) 0.30 0.30Lightening rod Loss (dB) 0.20 0.20TMA Insertion Loss (dB) 0.00TX Antenna Gain (dBi) 0.00 17.00EIRP (dBm) 33.00 62.55
Antenna Diversity Gain (dB) 3.00RX Sensitivity (dBm) -112.00 -102.00TMA Contribution to Sens. (dB) 0.00RX Antenna Gain (dBi) 17.00 0.00FWDR (dB) 2.00IRC (dB) 0.00Acceptance Level (dBm) -73.00Log-Normal Margin (dB) 8.70Allowed Max Path Loss (dB) 127.08 126.85Uplink-Downlink (dB) 0.23Limited DL LimitedAllowed Max Path Loss (dB) 126.85SSdesign (dBm) -64.30SSacceptance (dBm) -73.00BTS Antenna Height (m) 25.00MS Antenna Height (m) 1.50
Area Coverage Probability 95%Cell Radius (km) 1.09
Table 2-2 Link Budget for GSM S2-type Sites (DDT+FWDR) Configuration by RU60
2.1.2.3 GSM900 S8
RU60 S8 (2*RU60)EGSM/900M,MU
UpLink DownLinkTX Rank-top Output Power(dBm) 33.00 41.76DDT (dB) 0.00
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Total Cable Loss (dB) 2.22 2.22Feeder Loss (dB) 1.16 1.16Jumper Loss (dB)
0.56 0.56Connector Loss (dB) 0.30 0.30Lightening rod Loss (dB) 0.20 0.20TMA Insertion Loss (dB) 0.00TX Antenna Gain (dBi) 0.00 17.00EIRP (dBm) 33.00 56.54
Antenna Diversity Gain (dB) 3.00RX Sensitivity (dBm) -112.00 -102.00TMA Contribution to Sens. (dB) 0.00RX Antenna Gain (dBi) 17.00 0.00FWDR (dB) 0.00IRC (dB)
0.00Acceptance Level (dBm) -73.00Log-Normal Margin (dB) 8.70Allowed Max Path Loss (dB) 125.08 120.84Uplink-Downlink (dB) 4.24Limited DL LimitedAllowed Max Path Loss (dB) 120.84SSdesign (dBm) -64.30SSacceptance (dBm) -73.00BTS Antenna Height (m) 25.00MS Antenna Height (m) 1.50
Area Coverage Probability 95%Cell Radius (km) 0.74
Table 2-3 Link Budget for GSM S8-type Site Configuration by RU60
For this case, S8 adopts two RU60, and each RU60 supports 4 carriers,
thus the cabinet-top power of each carrier is 15W (41.76dBm).
2.1.2.4 GSM900 S4+UMTS900 S1
S4 (G) + S1 (U)
EGSM/900M,MUUpLink DownLink
TX Rank-top Output Power(dBm) 33.00 40.00DDT (dB) 0.00Total Cable Loss (dB) 2.22 2.22Feeder Loss (dB) 1.16 1.16Jumper Loss (dB) 0.56 0.56Connector Loss (dB) 0.30 0.30Lightening rod Loss (dB) 0.20 0.20TMA Insertion Loss (dB) 0.00
TX Antenna Gain (dBi) 0.00 17.00
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EIRP (dBm) 33.00 54.78 Antenna Diversity Gain (dB) 3.00RX Sensitivity (dBm)
-112.00 -102.00TMA Contribution to Sens. (dB) 0.00RX Antenna Gain (dBi) 17.00 0.00FWDR (dB) 0.00IRC (dB) 0.00Acceptance Level (dBm) -73.00Log-Normal Margin (dB) 8.70Allowed Max Path Loss (dB) 125.08 119.08Uplink-Downlink (dB) 6.00Limited DL LimitedAllowed Max Path Loss (dB) 119.08SSdesign (dBm) -64.30SSacceptance (dBm) -73.00BTS Antenna Height (m) 25.00MS Antenna Height (m) 1.50
Area Coverage Probability 95%Cell Radius (km) 0.66
Table 2-4 Link Budget for Configuring GSM900 S4+UMTS900 S1 by one RU60
For GSM900 S4+UMTS900 S1, the cabinet-top power of four GSM
carriers is 10W, and the cabinet-top power of UMTS carriers is 20W.
2.2 RSU60
2.2.1 Typical Sites Configuration
2.2.1.1 GSM Single Frequency Band Networking
2.2.1.1.1 S1~6
When a single sector has less than 6 or 6 TRXs, each cell should be
configured with one RSU60 and a pair of duplex & dual-polarized antennas.
The BBU should be configured as per total number of physical GSM carriers,
and each UBPG board can support 12 TRXs at maximum.
The cabinet-top output power of each cell is 80W, and the power is equally
allocated to each TRX. For cabinet-top output power under different carrier
configurations of RU60, please refer to section Erreur ! Source du renvoi
introuvable. .
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Select RSU60-900 for 900MHz GSM independent networking, and select
RSU60-1800 for 1800MHz GSM independent networking.
The antenna feeder connection of RU60 is as shown in following figure:
Figure 2-11 S1 to 6 Carriers Configuration for RSU60
2.2.1.1.2 S7~12
When a single sector has more than 6 TRXs (7 to 12 TRXs/cell), each cell
needs to be configured with two RSU60 modules and only one duplex &
dual-polarized antenna is needed. Two RSU60 are bridged via extended RX
interface and no external combiner is needed. The BBU should be configured
as per total number of physical GSM carriers, and each UBPG board can
support 12 TRXs at maximum.
For cabinet-top output power under different carrier configurations of RU60,
please refer to section Erreur ! Source du renvoi introuvable. .
For example, when a cell is configured with 8 TRXs, two RSU60 should be
used, each one is configured with 4 carriers, and each carrier has a cabinet-top
output power of 20W.
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Select RSU60-900 for 900MHz GSM independent networking, and select
RSU60-1800 for 1800MHz GSM independent networking.
The specific antenna connection is as shown as follows:
Figure 2-12 7 to 12 Carriers Configuration for RSU60
2.2.1.1.3 S1~6 (DDT+FWDR)
When DDT and FWDR are adopted, each cell must be configured with two
RSU60s, and two duplex & dual-polarized antennas are also needed. As those
two RSU60 transmit the same signals, the TRXs are thought as the same TRX
logically. At this time, the quantity of the baseband board needs to be
calculated as per the quantity of physical TRX, for example, for S4/4/4 underDDT + FWDR mode, the baseband board (two UBPG boards) quantity should
be calculated as per 24 TRXs.
For cabinet-top output power under different carrier configurations of
RSU60, please refer to section Erreur ! Source du renvoi introuvable. .
Select RSU60-900 for 900MHz GSM independent networking, and select
RSU60-1800 for 1800MHz GSM independent networking.
The specific antenna connection is as shown as follows:
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Figure 2-13 1 to 6 Carriers Configuration (DDT + FWDR) for RSU60
2.2.1.2 GSM900/1800 Dual Frequency Band Networking
The configuration principle of dual frequency band networking is the same
with that of single frequency band networking, and the difference is: as each
RSU60 module can only support a frequency band, the dual frequency cell
needs two RU modules at minimum. For example, for GSM900 S2+GSM1800
S2, each cell needs to be configured with a RSU60-900 and a RSU60-1800.
And the baseband board quantity is calculated as per total TRX quantity under
dual frequency mode.
For cabinet-top power calculation of GSM900/1800, please refer to section
Erreur ! Source du renvoi introuvable. .
If the antenna feeder configuration needs to be jointly shared, an external
broadband combiner is also needed.
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Figure 2-14 RSU60 GSM900/1800 Dual Frequency Networking (Antenna Unshared)
2.2.2 Link Budjet Examples
Caution:
All following link budget results can only be taken as reference, and should not
be quoted in link budget of any project, as the estimation result is of no
usability and is not informative. Any one who quotes the estimation result
directly in any specific project will undertake corresponding result.
Hypothesis:
900M frequency band, common urban area (MU), adopting Okumura-Hata
module, antenna mounting height supposed to be 25m, and 7/8 main feeder
cable.
For GSM900/1800 dual frequency band networking, the link budget needs
to be conducted respectively; please refer to following link budget examples.
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2.2.2.1 S2/S4/S8
RSU60 S2 RSU60 S4
RSU60
S8(2*RSU60)EGSM/900M,MU EGSM/900M,MU EGSM/900M,MUUpLink DownLink UpLink DownLink UpLink DownLink
TX Rank-top Output Power(dBm) 33.00 46.02 33.00 44.77 33.00 44.77DDT (dB) 0.00 0.00 0.00Total Cable Loss (dB) 2.22 2.22 2.22 2.22 2.22 2.22Feeder Loss (dB) 1.16 1.16 1.16 1.16 1.16 1.16Jumper Loss (dB) 0.56 0.56 0.56 0.56 0.56 0.56Connector Loss (dB) 0.30 0.30 0.30 0.30 0.30 0.30Lightening rod Loss (dB) 0.20 0.20 0.20 0.20 0.20 0.20TMA Insertion Loss (dB) 0.00 0.00 0.00TX Antenna Gain (dBi) 0.00 17.00 0.00 17.00 0.00 17.00EIRP (dBm) 33.00 60.80 33.00 59.55 33.00 59.55
Antenna Diversity Gain (dB) 3.00 3.00 3.00RX Sensitivity (dBm) -112.00 -102.00 -112.00 -102.00 -112.00 -102.00TMA Contribution to Sens. (dB) 0.00 0.00 0.00RX Antenna Gain (dBi) 17.00 0.00 17.00 0.00 17.00 0.00FWDR (dB) 0.00 0.00 0.00Acceptance Level (dBm) -73.00 -73.00 -73.00Log-Normal Margin (dB) 8.70 8.70 8.70Allowed Max Path Loss (dB) 125.08 125.10 125.08 123.85 125.08 123.85Uplink-Downlink (dB) -0.02 1.23 1.23Limited UL Limited DL Limited DL LimitedAllowed Max Path Loss (dB) 125.08 123.85 123.85SSdesign (dBm) -64.30 -64.30 -64.30SSacceptance (dBm) -73.00 -73.00 -73.00BTS Antenna Height (m) 25.00 25.00 25.00MS Antenna Height (m) 1.50 1.50 1.50
Area Coverage Probability 95% 95% 95%Cell Radius (km) 0.76 0.70 0.70
Table 2-5 Link Budget for GSM S2 and S3 Configuration by RSU60
It can be seen from above table that when configuring GSM900 S2, S4
and S8 type sites by RSU60, only the cabinet-top output power is different, and
all other link budget parameters are the same. For S2 type site, the cabinet-top
power is 40W (46.02dBm) and for S4 type site, the cabinet-top power is 20W
(43.01dBm)
2.2.2.2 S2 (DDT+FWDR)
RSU60S2(DDT+FWDR)
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EGSM/900M,MUUpLink DownLink
TX Rank-top Output Power(dBm) 33.00 46.02DDT (dB) 3.00Total Cable Loss (dB) 2.22 2.22Feeder Loss (dB) 1.16 1.16Jumper Loss (dB) 0.56 0.56Connector Loss (dB) 0.30 0.30Lightening rod Loss (dB) 0.20 0.20TMA Insertion Loss (dB) 0.00TX Antenna Gain (dBi) 0.00 17.00EIRP (dBm) 33.00 63.79
Antenna Diversity Gain (dB) 3.00RX Sensitivity (dBm) -112.00 -102.00TMA Contribution to Sens. (dB) 0.00RX Antenna Gain (dBi) 17.00 0.00FWDR (dB) 2.00Acceptance Level (dBm) -73.00Log-Normal Margin (dB) 8.70Allowed Max Path Loss (dB) 127.08 128.09Uplink-Downlink (dB) -1.01Limited UL LimitedAllowed Max Path Loss (dB) 127.08SSdesign (dBm) -64.30SSacceptance (dBm) -73.00BTS Antenna Height (m) 25.00MS Antenna Height (m) 1.50
Area Coverage Probability 95%Cell Radius (km) 0.87
Table 2-6 Link Budget for GSM S2 (DDT + FWDR) by RU60
2.3 BS8700 (R8860 + B8200)
B8200+R8860 constitute to distributed BS8700, namely BBU + RRU mode.
It can be widely used for coverage of special scenarios including indoor, tunnel,
high-speed railway, highway, dense urban area and other areas. RF remote
mode poses lower requirements for the equipment room, and R8860
local-antenna installation can save feeder cable loss and provides more flexible
site deployment scheme. BBU is generally placed indoor and connected to
RRU via optical fiber.
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B8200 and R8860 networking can be in star topology, chain topology and
hybrid topology.
For star networking, two FS board are configured to provide 12 optical
interfaces for connecting with 12 RRUs;
For chain networking, currently the maximum cascade depth of RRU is 4
tiles;
For hybrid networking, 48 RRUs can be supported at maximum.
The networking topology structure for B8200 & RNC/BSC as well as RRU
is as shown in following figure:
Figure 2-15 Sketch Map for Networking of B8200, RNC/BSC and RRU
2.3.1 Typical Sites Configuration
The typical site configuration of R8860 is consistent with that of RU60, and
the conversion method of cabinet-top power is also the same. No more details
are provided here repeatedly. The link budget difference with RU60 is that the
feeder cable loss needs to be re-considered after adopting R8860 RF remote
mode.
Herein under introduction to antenna feeder connection of R8860 under
conventional configurations are given.
2.3.1.1 Each Pair of Antennas Connected with One RRU
When each pair of dual-polarized antennas is connected to one RRU, the
RX/TX and RX interfaces of RRU are respectively connected to two interfaces
of the dual-polarized antennas.
Emission channel: RX/TX interface of RRU.
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Reception channel: main set reception comes from RX/TX interface and
diversity reception comes from RX interface.
Figure 2-16 Each Pair of Antennas Connected with One RRU
2.3.1.2 Each Pair of Antennas Connected with 2 RRUs
When each pair of dual-polarized antennas is connected to two RRUs, the
RX/TX interfaces of each RRU are respectively connected to two interfaces ofthe dual-polarized antennas. Secondly, for two RRUs, connect the RXOUT
interface of RRU1 with RXIN interface of RRU2, and connect the RXIN
interface of RRU1 with RXOUT interface of RRU2.
Emission channel: two RRU2 transmit signals via respective RX/TX
interfaces.
Reception channel: two RRUs collect main set reception signals via their
respective RX/TX interfaces, and the diversity reception signals are gained
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through connecting RXOUT interface of one RRU with RXIN interface of the
other.
Figure 2-17 Each Pair of Antennas Connected with 2 RRUs
2.3.2 Feeder Cable Loss Consideration
2.3.2.1 RRU Installed Close to Antenna
Under permissible conditions (such as tower load bearing, wind speed and
other factors), RRU can be installed close to the antenna, RRU and BBU are
connected via optical fiber, and RRU and an tenna are connected via 1/2 soft jumper.
Under such conditions, the feeder cable loss only refers to the loss of 1/2
soft jumper between RRU and the antenna as well as the loss between two
connectors. The 1/2 feeder cable is generally at the length o f 2m, or can be
configured as per actual conditions. And no lightning arrester is configured
under such conditions.
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Figure 2-18 Sketch Map for Antenna Installed Close to the RRU
For example, for near antenna installation of R8860-900, RRU and the
antenna are connected via 1/2 super soft jumper at a length of 2M, under such
conditions, the feeder cable loss is 11.2/100*2+2*0.05=0.32dB. No lightning
arrester is configured under such conditions.
Caution:
Whether the RRU can be installed close to the antenna should be understood
by communicating with the market department in tendering process, and the
link budget can then be made accordingly.
2.3.2.2 RRU Installed Close to the Platform
If the conditions are non-permissible, the RRU can only be installed on the
tower platform (the platform below the antenna) or on the roof platform. Under
such conditions, the RRU and BBU are still connected via optical fiber; the
RRU and the antenna are connected in conventional mode: 1/2 sof t jumper at
both ends + main feeder cable (7/8, 5/4 or 1 -5/8 feeder cable). The length of
the main feeder cable is equal to the height from RRU to the antenna, and the
length of two 1/2 soft jumpers is generally 22m=4m. Under such conditions,
the lightning arrester should be configured.
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Figure 2-19 Sketch Map for RRU Installed Close to the Platform
Summary table for feeder cable loss (taking Hansen product for an
example):
Feeder Type 900M 1800M Unit
1/2 Jumper 11.2 16.6dB/100
m
7/8 Feeder 3.88 5.75
dB/100
m
5/4 Feeder 2.77 4.16
dB/100
m
1-5/8 Feeder 2.29 3.47
dB/100
m
Fiber 0 0
dB/100
m
Table 2-7 Summary Table for Hansen Feeder Cable Loss
The connector loss is 0.05 dB/piece.
MountHeight
of Antenna
(m)
PlatformMountingHeight ofRRU (m)
Lengthof 7/8Main
FeederCable
(m)
Lengthof 1/2Soft
Jumper(m)
Connector 900M(dB)1800M
(dB)
50 0 50 4 6 2.89 4.0450 10 40 4 6 2.5 3.46
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50 20 30 4 6 2.11 2.8950 30 20 4 6 1.73 2.3150 40 10 4 6 1.34 1.7450 50 0 2 2 0.32 0.43
Table 2-8 Examples for Feeder Cable Loss at Different RRU Mounting Heights
Prompt:
If the RRU can not be installed close to the antenna, its location should be
understood by communicating with the market department in tendering process,
including details related to the height of the tower platform for placing RRU. And then the feeder cable length and loss can be calculated according to the
height of the platform when making link budget.
2.3.3 Application of Multi-carrier Association
Multi-carrier association is a product imported from OTSR of 3G into GSM,
it permits a logical cell to have antennas at multiple positions and multiple
angles and adopts multiple RRUs for transmitting the same carrier on different
antennas. It is different with traditional STSR networking, and is suitable to be
used for dense urban areas with complex transmission environment (such as
Hong Kong) as well as high speed mobile scenarios (such as high-speed
railway, highway). It can greatly reduce inter-cell handover/reselection, and is
in favor of enhancing network performance and subscriber acknowledgement.
Terminology explanation:
STSR: Sectorized TX Sectorized RX (each cell has only one coverage area
with repeater system excluded). Such networking mode is the networkingmode for conventional omni-directional site or N-sectorized directional site.
OTSR: Omni TX Sectorized RX (each cell is allowed to have multiple different
coverage areas). Such networking mode allows one logical cell to have
multiple antennas placed at different locations and different angles. OTSR can
be implemented by traditional power splitter or by SDR multi-carrier unite
combine mode.
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MCUM (Multi Carrier Unite Combine): it refers to connection of M RRUs and N
pairs of antennas (M is a multiple of N, and the value can be 1, 2 .), the
carriers of all those RRUs belong to the same cell, the downlink emission
signals of multiple RRUs are completely the same, and selectable combination
is performed in the downlink process.
Explanations to differences between traditional 3-sectors STSR and OTSR
are given as follows by analyzing following two figures.
2.3.3.1 STSR Example
The following figure is a sketch map for configuring a STSR-3 sector intoS8/8/8. Each sector supports 8-TRXs and is configured with two RRUs. Each
RRU is configured with 4 TRXs. The antenna direction of Cell 1 is 30 degrees,
Cell 2 60 degrees, and Cell 3 90 degrees.
The first RRU of each sector is connected with FS board of BBU, and the
second RRU of each sector is in cascade with the first RRU via optical fiber.
Each UBPG board can process 12-channel baseband signals. As S8/8/8 STSR
totally has 24 TRXs, thus 2 UBPG boards are needed.
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Figure 2-20 Sketch Map for Configuring STSR-3 Sector into S8/8/8
2.3.3.2 Example for Implementing OTSR Function Via Traditional Power SplitterThe power splitter mode is applicable to any BTS. For example, when
B8018 is configured into OTSR-2 02 type site with 2 TRXs, the cabinet-top
power is 20W. As the power splitter is used, the power is reduced to 10W with
3dB power splitter loss.
To implement OTSR by power splitter, an extra 3dB loss is caused, thus
the cabinet-top power is half reduced.
Figure 2-21 Implementing OTSR by Power Splitter
2.3.3.3 Example for Implementing OTSR Via MCUM (Multi Carrier Unite Combine)
To configure OTSR-2 O2 type site by MUCM mode, two R8860 are
configured, and each R8860 is configured with 2 TRXs. The cabinet-top output
power is 30W. To implement OTSR by MCUM mode will not cause extra loss.
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Figure 2-22 Implementing OTSR by MCUM
The following figure is a sketch map for configuring OTSR-3 sector into 08
type site by MCUM function. The angles of the three antennas are the same
with above mentioned conditions, which are respectively 30 degrees/60
degrees/90 degrees, and the three antennas (Antenna 1, Antenna 2 and Antenna 3) can be placed in three different places rather than in the same
position, but the three antennas belong to the same logical Cell 1.
Each Antenna is connected to two RRUs with 8 TRXs supported, but those
8 TRXs are completely same in three antenna directions, thus the capacity of
Cell 1 is not O24 but O8. 8 TRXs in each antenna direction are configured with
completely the same frequency points, thus can be seen as the same emission
signal which acquires downlink transmit diversity gains. At the same time, as
the uplink signals are received via different antennas, the selectablecombination can bring a certain uplink diversity gains.
The first RRU connected with each antenna is connected with FS board of
BBU via optical fiber, and the second RRU is in cascade with the first RRU via
optical fiber. Although the actual capacity of Cell 1 is O8, as the baseband part
still needs to process 38=24 baseband signals, the quantity of UBPG board is
2 pieces.
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Figure 2-23 Sketch Map for OTSR-3 O8
Note:
In the above figure, X, X and X correspond to the same carrier transmitted by
Antenna1/2/3.
Caution 1:
For OTSR networking, the quantity of UBPG board can not be calculated
according to actual logic capacity of OTSR BTS but according to the quantity of
physical carriers configured. In the above example, one OTSR-3 O8-type site
has logic capacity of 8 TRXs, but the number of actual physical carrier is
83=24, thus it should be configured with 2 UBPG boards. Another examplerefers to a OTSR-5 (five directional antennas) O10-type site, the actual UBPG
board quantity should be calculated according to the number of physical
carriers: 510=50, and totally 5 UBPG boards should be configured.
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Caution 2:
For OTSR, the same carrier must be implemented on the same UBPG board. For OTSR-5 O10-type site shown in following figure, each UBPG board is
actually configured with 2 logic carriers (2), the other eight TRXs (2/2/2/2)
are the same signals with (2), and the actual number of physical carriers
configured on each UBPG board is 10. Five UBPG boards can not be
configured into the format of 10+10+10+10+10.
Figure 2-24 Sketch Map for OTSR-5 O10
Caution 3:
For OTSR networking, the hardware quantities of RRU and UBPG need to be
increased. A traditional 08-type site needs two RRUs and one UBPG board.
However, for a OTSR-3 08-type site, six RRUs and two UBPG boards are
needed.
For influences of MCUM on coverage/capacity/frequency planning/network
performance and applicable special scenarios, please refer to the article of
Special Subject Research---Analysis for Application of GSM SDR Equipment in
OTSR Networking .
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2.3.4 Factors to be Considered for OTSR Link Budget
In downlink direction, as multiple antennas transmit the same signal, the
incoherent emission energy is input for countermining poor C/I caused by
multipath effect, acquiring a certain downlink emission diversity gains valued at
2dB.
In uplink direction, the same logic cell has multiple antennas for diversity
reception, after processing via MRC combination, it can be thought as having
acquired 2dB 4-channel diversity reception gains.
2.3.5 Link Budget Examples
Caution:
All following link budget results can only be taken as reference, and should not
be quoted in link budget of any project, as the estimation result is of no
usability and is not informative. Any one who quotes the estimation result
directly in any specific project will undertake corresponding result.
2.3.5.1 Link Budget for STSR Networking
Hypothesis:
900M frequency band, common urban area (MU), adopting Okumura-Hata
module, antenna mounting height supposed to be 25m, case 1: R8860 is not
placed on the tower, and RRU and the antenna are connected via 7/8 main
feeder cable; case 2: R8860 is installed on the tower and close to the antenna,
and the loss of the 2m 1/2 super soft jumper cable should be taken into
consideration.
R8860 2TRX R8860 2TRXEGSM/900M,MU EGSM/900M,MU
UpLink DownLink UpLink DownLinkTX Rank-top Output Power(dBm) 33.00 44.77 33.00 44.77DDT (dB) 0.00 0.00Total Cable Loss (dB) 2.03 2.03 0.32 0.32Feeder Loss (dB) 0.97 0.97 0.00 0.00Jumper Loss (dB) 0.56 0.56 0.22 0.22Connector Loss (dB) 0.30 0.30 0.10 0.10
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Lightening rod Loss (dB) 0.20 0.20 0.20 0TMA Insertion Loss (dB) 0.00 0.00TX Antenna Gain (dBi)
0.00 17.00 0.00 17.00EIRP (dBm) 33.00 59.74 33.00 61.45 Antenna Diversity Gain (dB) 3.00 3.00RX Sensitivity (dBm) -112.00 -102.00 -112.00 -102.00TMA Contribution to Sens. (dB) 0.00 0.00RX Antenna Gain (dBi) 17.00 0.00 17.00 0.00FWDR (dB) 0.00 0.00Acceptance Level (dBm) -73.00 -73.00Log-Normal Margin (dB) 8.70 8.70Allowed Max Path Loss (dB) 125.27 124.04 126.98 125.75Uplink-Downlink (dB) 1.23 1.23Limited DL Limited DL LimitedAllowed Max Path Loss (dB) 124.04 125.75SSdesign (dBm) -64.30 -64.30SSacceptance (dBm) -73.00 -73.00BTS Antenna Height (m) 25.00 25.00MS Antenna Height (m) 1.50 1.50
Area Coverage Probability 95% 95%Cell Radius (km) 0.91 1.02
Table 2-9 Link Budget for Tower-off Installation and Near-Antenna Installation of R8860
2.3.5.2 Link Budget for MCUM Configuration (OSTR Networking)
Hypothesis
900M frequency band, high density urban area (HMU), adopting
Okumura-Hata module, and antenna mounting height supposed to be
25m.When R8860 is installed on the tower at a position near to the antenna,
the loss of the 2m 1/2 super soft jumper cable should be taken into
consideration. MCUM (three antenna directions) and traditional 3-sector BTS
can be respectively adopted.
R8860 STSR 2TRX R8860 OTSR 2TRXEGSM/900M,DU EGSM/900M,DU
UpLink DownLink UpLink DownLinkTX Rank-top Output Power(dBm) 33.00 44.77 33.00 44.77Tx Diversity (dB) 0.00 2.00Total Cable Loss (dB) 0.32 0.32 0.32 0.32Feeder Loss (dB) 0.00 0.00 0.00 0.00
Jumper Loss (dB) 0.22 0.22 0.22 0.22
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Connector Loss (dB) 0.10 0.10 0.10 0.10Lightening rod Loss (dB) 0 0 0 0TMA Insertion Loss (dB)
0.00 0.00TX Antenna Gain (dBi) 0.00 17.00 0.00 17.00EIRP (dBm) 33.00 61.45 33.00 64.45
Antenna Diversity Gain (dB) 3.00 3.00RX Sensitivity (dBm) -112.00 -102.00 -112.00 -102.00TMA Contribution to Sens. (dB) 0.00 0.00RX Antenna Gain (dBi) 17.00 0.00 17.00 0.00FWDR (dB) 0.00 2.00Acceptance Level (dBm) -73.00 -73.00Log-Normal Margin (dB) 8.70 8.70Allowed Max Path Loss (dB) 126.98 125.75 128.98 127.75Uplink-Downlink (dB) 1.23 1.23Limited DL Limited DL LimitedAllowed Max Path Loss (dB) 125.75 127.75SSdesign (dBm) -64.30 -64.3SSacceptance (dBm) -73.00 -73BTS Antenna Height (m) 25.00 25MS Antenna Height (m) 1.50 1.5
Area Coverage Probability 95% 95%Cell Radius (km) 1.02 1.16
Table 2-10 Link Budget for R8860 STSR & OTSR Application