SITE DIVERSITY AGAINST RAIN FADING IN LMDS SYSTEMS

ZAID AHMED SHAMSAN ABDO

A thesis submitted in partially fulfillment of the

requirements for the award of the degree of

Master of Engineering

(M Eng. Electrical-Electronics and Telecommunications)

Faculty of Electrical Engineering

Universiti Technologi Malaysia

MAY 2007

iii  

 

 

To my beloved parents, to my beloved wife, to our sons Osamah and

Mohammad, and to our daughters Sumaih and Shadha.

iv  

ACKNOWLEDGEMENT

In the name of Allah, the Most gracious, the Most Merciful. Firstly, all

commendation to Allah for the incredible gift bestowed upon me and for give me the

determination to pursue with this study and enable me to prepare this thesis.

I deeply appreciate the inspirations and guideline that I have received from

my supervisor PM Dr. Jafri Bin Din for his personal kindness, skill, patience,

valuable advice and encouragement.

I would like to thank all of my family and all my friends for their moral

support on me for completing this work.

v  

ABSTRACT

Local Multipoint Distribution Service (LMDS) is a new terrestrial fixed radio

technology for broadband communication applicable that can be used to provide digital

two-way voice, data, Internet, and video services or other digital services requiring

high capacity traffic channels. LMDS is a point to multipoint wireless system operating

at frequencies above 20 GHz, the most serious impairment at these frequencies is rain

fading. In the system point of view a moving rain cell over the LMDS service area will

not only attenuate the desired signal but also the interferer. Many techniques could be

used to overcome rain fading. Applying Site Diversity as a possible solution to reduce

the effect of rain is necessary, because a rain-cell degrades the system performance at

a part of the service area but the rain can improve the carrier signal conditions

elsewhere depending on the locations of the Base Station, Terminal Station and the

rain-cell. The rain attenuation of different locations in Malaysia region in a given

LMDS is calculated and the effects of a moving rain cell over an LMDS system are

analyzed, different situations of interference according to the position of the rain-cell

over the service area of LMDS are elaborated. The site diversity is implemented based

on the ITU-R Recommendations to enhancement LMDS. The location dependent C/I

in the LMDS service area under rainy conditions with and without site diversity

technique is calculated and simulated. Different cell sizes of LMDS with and without

site diversity are considered in this project for significant analyses and discussions. It is

found that site diversity has high ability to improve the performance level of all LMDS

service area specially under rainy conditions.

 

 

 

 

vi  

 

 

 

ABSTRAK

 

 

Local Multipoint Distribution Service (LMDS) adalah suatu teknologi baru

daripada radio bumi yang ditetapkan untuk komunikasi jalur lebar yang dapat

digunakan untuk menyediakan jalur digital suara dua hala, data, Internet, dan

perkhidmatan video atau perkhidmatan digital lainnya yang memerlukan saluran trafik

berpasitas tinggi. LMDS adalah suatu sistem titik ke banyak titik dari media tanpa

wayar yang beroperasi pada frekuensi di atas 20 GHz, kebanyakan pelemahan

rangkaian pada frekuensi ini adalah pemudaran oleh hujan. Jika dilihat dari prespektif

system LMDS, sel hujan yang bergerak melepasi kawasan perkhidmatan LMDS bukan

sahaja melemahkan isyarat yang diterima, tetapi turut mengganggunya. Banyak cara

dapat digunakan untuk mengatasi masalah pemudaran hujan. Teknik kepelbagaian

lawan dapat digunakan sebagai kemungkinan mengurangi kesan hujan. Sel hujan akan

melemahkan prestasi perkhidmatan pada sebahagian kawasan liputan tetapi akan

meningkatkan prestasi perkhidmatan bergantung kepada kedudukan stesen tapak,

stesen terminal dan sel hujan. Pelemahan hujan pada beberapa lokasi LDMS di

Malaysia telah ditentukan dengan mengambilkira kesan pergerakan sel hujan melepasi

kawasan LDMS. Perbezaan situasi gangguan disebabkan oleh perbezaan kedudukan

sel hujan telah dilaporkan. Prestasi LDMS dinilai berdasarkan pengalaman

perlaksanaan perkhidmatan LDMS. Teknik kepelbagaian laluan dilaksanakan

berdasarkan rekomendasi ITU-R. Lokasi bersandar C/I dalam perkhidmatan LDMS

ketika hujan dengan dan tanpa teknik kepelbagaian lawan dihitung dan disimulasikan.

Perbezaan saiz sel LMDS diambilkira dalam perbincangan dan analisa kajian. Ini

didapati bahawa teknik kepelbagaian lawan mempunyai keupayaan yang tinggi bagi

mempertingkatkan tahap prestasi semua kawasan perkhidmatan LMDS terutamanya

pada waktu hujan.

vii  

TABLE OF CONTENTS

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

CHAPTER

TITLE

DECLARATION

DEDICATION

ACKNOWLEDGEMENTS

ABSTRACT

ABSTRAK

TABLE OF CONTENTS

LIST OF FIGURES

LIST OF TABLES

LIST OF ABBREVIATIONS

LIST OF APPENDICES

INTRODUCTION

1.1 Background

1.2 Objective of the Project:

1.3 Scope of the Project

1.4 Methodology of the Project

1.5 Thesis Outline

LOCAL MULTIPOINT DISTRIBUTION SERVICE

AND RAIN FADING

2.1  Introduction

2.2 Basic Principles

PAGE

ii

iii

iv

v

vi

vii

xi

xiv

xv

xvii

1

1

3

3

3

4

6

6

8

1.

2.

viii  

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

  3.

2.2.1 Advantages/Disadvantages of LMDS

2.2.2 Applications and Service Performance

2.2.3 Frequency Band and Spectrum Allocation

2.3 Wireless Links and Access Options

2.3.1 TDMA or FDMA Selection

2.4 Cell planning  

2.5 Link Budget Calculation

2.6 Dynamic Bandwidth Allocation

2.7 C/I and Inter-Cellular Interference

2.8 The Rain Fading

2.8.1 Introduction

2.8.2 Rain Effects

2.8.3 Rain Attenuation Equation

2.8.4 Rain-Cell over LMDS System

2.9 Effects of Rain Fading on the Efficiency of the

Ka-Band LMDS System

2.9.1 Interference Analysis of the Boundary Subscriber

2.9.2 Channel Capacity in Rain Fading

2.9.3 Bit Error Rate

2.9.4 Cell-Coverage Effect

SITE DIVERSITY TECHNIQUE

3.1 Introduction

3.2 Site Diversity

3.3 Diversity Gain and Diversity Improvement Concepts

3.3.1 Cell-Site Diversity Performance

3.3.2 Cell-Site Diversity Performance Measures

3.4 Influenced Factors

10

13

13

15

17

17

19

20

21

23

23

24

25

27

28

29

30

31

32

33

33

34

36

36

38

40

ix  

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

4.

5.

PROJECT METHODOLOGY

4.1 Introduction 

4.2 Establishing of LMDS Network

4.3 Calculation of Rain Attenuation

4.3.1 Specific Rain Attenuation

4.3.2 Effective Path Length

4.3.3 Rain Attenuation

4.4 Rain Cell Movement within LMDS

4.5 Site Diversity Implementation

RESULTS AND ANALYSIS

5.1 Introduction

5.2 LMDS Configuration

5.3 LMDS Frequencies and Parameters

5.4 Rain Attenuation Data and Calculations

5.4.1 Specific Rain Attenuation Calculation

5.4.2 Effective Path Length Calculation

5.4.3 Rain Attenuation Calculation

5.4.3.1 Rain Attenuation at 24 GHz

5.4.3.2 Rain Attenuation at 26 GHz

5.4.3.3 Comparison between Rain Rates Attenuation at

Different Frequencies

5.5 Terminal Station Situation Possibilities

5.5.1 All LMDS Service Area with Rain and without Rain

5.5.2 The Four Cases and Rain Cell Movement Effects over

LMDS

42

42

43

45

46

46

47

47

47

49

49

50

51

52

52

53

54

54

56

58

60

61

63

x  

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

6.

 

5.5.2.1 Effect of Rain Movement on the Received

Signal at 24 GHz

5.5.2.2 Effect of Rain Movement on the Received

Signal at 26 GHz 

5.6 Maximum Coverage & Different Sector Size

5.6.1 Relationship between Sector Size and Maximum

Coverage at 24 GHz

5.6.2 Relationship between Sector Size and Maximum

Coverage at 26 GHz

5.7 Site Diversity Implementation and Calculations

5.7.1 LMDS with Site Diversity

5.7.1.1 Site Diversity Calculations at 24 GHz

5.7.1.2 Site Diversity Calculations at 26 GHz

5.7.1.3 Overall Average C/I values of LMDS with and

without Site Diversity

5.8 Site Diversity with Different Cell Sizes of LMDS

CONCLUSION AND FUTURE WORK

6.1 Summary

6.2 Conclusion

6.3 Future Work

63

65

67

67

69

72

73

73

75

77

79

84

84

85

86

87

91- 104

REFERENCES

Appendices A - H

xi  

LIST OF FIGURES

TITLE

Illustration of an LMDS network

The operation of LMDS for broadcast and interactive services

Multipath propagation and LMDS systems

LMDS band allocation

FDMA access

TDMA access

Frequency plan for an LMDS service

Inter-Cellular Interference

Typical scenario of cell-site diversity

Diversity gain and diversity improvement concepts

Geometrical configuration of a cell-site diversity scheme

Single and joint annual exceedance probability of rain

attenuation for typical diversity LMDS system

LMDS area structure

The supposed scenario of LMDS

Site diversity implementation

The supposed scenario of LMDS without site diversity

Rain attenuation vs. path length at 24 GHz and 96 mm/h

(Jelebu)

Rain attenuation vs. path length at 24 GHz and 125 mm/h

(Johor Bahru)

Rain attenuation vs. path length at 24 GHz and 145 mm/h

(Taiping)

PAGE

8

9

10

14

15

15

18

22

33

36

37

40

43

45

48

50

55

55

56

FIGURE No.

2.1

2.2

2.3

2.4

2.5

2.6

2.7

2.8

3.1

3.2

3.3

3.4

4.1

4.2

4.3

5.1

5.2

5.3

5.4

xii  

 

 

 

 

 

Rain attenuation vs. path length at 26 GHz and 96 mm/h (Jelebu)

Rain attenuation vs. path length at 26 GHz and 125 mm/h

(Johor Bahru)

Rain attenuation vs. path length at 26 GHz and 145 mm/h (Taiping)

Rain attenuation vs. rain rates at 24 GHz

Rain attenuation vs. rain rates at 26 GHz

All LMDS with rain and without rain at 24 GHz

All LMDS with rain and without rain at 26 GHz

The four cases under 24 GHz and 96 mm/h conditions

The four cases under 24 GHz and 125 mm/h conditions

The four cases under 24 GHz and 145 mm/h conditions

The four cases under 26 GHz and 96 mm/h conditions

The four cases under 26 GHz and 125 mm/h conditions

The four cases under 26 GHz and 145 mm/h conditions

Maximum coverage vs. different sector size of worst case at

24 GHz and 96 mm/h

Maximum coverage vs. different sector size of worst case at

24 GHz and 125 mm/h

Maximum coverage vs. different sector size of worst case at

24 GHz and 145 mm/h

Maximum coverage vs. different sector size of worst case at

26 GHz and 96 mm/h

Maximum coverage vs. different sector size of worst case at

26 GHz and 125 mm/h

Maximum coverage vs. different sector size of worst case at

26 GHz and 145 mm/h

Implementation of site diversity

LMDS with and without site diversity at 24 GHz and 96 mm/h

LMDS with and without site diversity at 24 GHz and 125 mm/h

LMDS with and without site diversity at 24 GHz and 145 mm/h

57

57

58

58

59

62

62

63

64

64

65

65

66

68

68

69

69

70

70

72

73

74

74

5.5

5.6

5.7

5.8

5.9

5.10

5.11

5.12

5.13

5.14

5.15

5.16

5.17

5.18

5.19

5.20

5.21

5.22

5.23

5.24

5.25

5.26

5.27

xiii  

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

5.28

5.29

5.30

5.31

5.32

5.33

5.34

5.35

5.36

LMDS with and without site diversity at 26 GHz and 96 mm/h

LMDS with and without site diversity at 26 GHz and 125 mm/h

LMDS with and without site diversity at 26 GHz and 145 mm/h

Site diversity vs. different sector sizes of worst case at 24GHz

and 96 mm/h

Site diversity vs. different sector sizes of worst case at 24GHz

and 125 mm/h

Site diversity vs. different sector sizes of worst case at 24GHz

and 145 mm/h

Site diversity vs. different sector sizes of worst case at 26GHz

and 96 mm/h

Site diversity vs. different sector sizes of worst case at 26GHz

and 125 mm/h

Site diversity vs. different sector sizes of worst case at 26GHz

and 145 mm/h

 

75

76

76

80

80

81

81

82

82

xiv  

LIST OF TABLES

TABLE NO.

2.1

2.2

2.3

2.4

2.5

2.6

5.1

5.2

5.3

5.4

5.5

5.6

5.7

5.8

5.9

5.10

5.11

TITLE

Capacity comparison of available access technologies

LMDS Advantages/Disadvantages

Parameters and formulas for LMDS

Key parameter of some modulation scheme

An example of calculation of rain attenuation

Relationship between reversed distance dR, rain rate RR and

cell size

The distance between terminal station and the effective

base stations

Parameters, formulas for LMDS (26GHz)

Parameters, formulas for LMDS (24GHz)

Specific rain attenuation

Effective path length value of effective signals

Rain attenuation at corner of LMDS cell

Maximum coverage during worst case without using site

diversity

Average C/I (dB) of LMDS service area at d= 4.2456 km

(24 GHz)

Average C/I (dB) of LMDS service area at d= 4.2456 km

(26 GHz)

Average C/I (dB) of LMDS service area at d= 2 km (24 GHz)

Average C/I (dB) of LMDS service area at d= 2 km (26 GHz)

PAGE

11

12

19

21

27

29

51

51

52

53

54

60

71

77

78

78

79

xv  

LIST OF ABBREVIATIONS

ADSL/VDSL -

ATM -

BER -

BS -

BSC -

BTS -

BWA -

C/B -

CDF -

CDMA -

C/I -

CPE -

DBA -

FCC -

FDMA -

FEC -

FTTH -

HFC -

HS -

ISI -

ITU-R -

LAN -

LMCS -

 

Asynchronous/Very High– Rate Digital Subscriber Line

Asynchronous transfer mode

Bit Error Rate

Base Station

Base Station Controller

Base Station Transceiver

Broadband wireless access

Channel Capacity

Cumulative Distribution Function.

Code Division Multiple Access.

Carrier to Interference ratio

Customer Premise Equipment

Dynamic Bandwidth Allocation

Federal Communications Commission

Frequency Division Multiple Access.

Forward error correction

Fiber-to-the-home.

Hybrid Fiber Coax

Hub Station

Inter-symbol Interference

International Telecommunication Union Radio-Broadcasting

Local Area Network

Local Multipoint Communication Systems

 

xvi  

LMDS -

LOS -

MCMC -

MSS -

NOC -

PDF -

PONs -

PSTN -

QAM -

QPSK -

SD -

SDBS -

S/I -

SNR -

SRSP -

TDMA -

TS -

WAN -

Local Multipoint Distribution Services.

Line of sight.

Malaysian Communications and Multimedia Commission

Mobile Satellite Service

Network Operations Center

Probability Density Function

Passive Optical Networks

Public Switch Telephone Networks

Quadrature Amplitude Modulation

Quadrature Phase Shift Keying

Site Diversity

Site Diversity Base Station

Signal-to-Interference Ratio.

Signal to noise ratio

Standard Radio System Plan

Time Division Multiple Access.

Terminal Station

Wide Area Network

 

xvii  

LIST OF APPENDICES

APPENDIX TITLE PAGE

Appendix A Part of the ITU-R Specific Attenuation Parameters 91

Appendix B LMDS Frequencies of Malaysia 92

Appendix C MATLAB Program for Rain Attenuation 93

Appendix D MATLAB Program for ALL LMDS with and

Without Rain 95 

Appendix E MATLAB Program for Possibilities Scenarios of

LMDS Area 97 

Appendix F MATLAB Program for the Worst Case Scenario

and Different LMDS Cell Sizes 100

Appendix G MATLAB Program for the Worst Case Scenario

by Using Site Diversity 102

Appendix H MATLAB Program for the Worst Case Scenario

and Different LMDS Cell Sizes by Using Site

Diversity Technique 104 

CHAPTER 1

INTRODUCTION

1.1 Background

There is a growing interest in providing broad-band services through local

access networks to individual users. Millimetric-wave radio solutions are considered

as the optimal delivery systems for these services. They are termed as broad-band

wireless access (BWA) systems or local multipoint distributed services LMDS.

(Panagopoulos et al., 2002).

The new broadband networks and services are developed continuously to

serve the different demands, e.g., Internet, mobile Internet, broadcasting, telephony,

e-commerce, Video on Demand, etc. Point-to-multipoint wireless system could be a

promising solution to connect the users to the backbone network instead of

broadband wired networks because of its cost efficiency, easy and fast installation,

and re-configurability; however due to the time and location variable channel

conditions the system should apply fade mitigation techniques to reach the quality of

service requirements. (Sinka and Bito, 2003).

The Ka (20/30 GHz) and V (40/50 GHz) frequency bands are becoming increasingly

attractive for user oriented future commercial satellite services, due to their large

available bandwidths. However, they suffer more from rain fades in comparison to

the almost congested Ku (12/14 GHz) band. Therefore, prediction models for annual

rain attenuation, such as the ones developed by several research groups over the past

2

three decades are required to provide guidance in the course of balancing availability

requirements and cost. (Panagopoulos et al., 2002).

To combat rain attenuation, several fade mitigation techniques have been

developed such as diversity protection schemes, power control and adaptive

processing techniques. Among these techniques, the most efficient is site diversity

(SD). SD takes advantage of the spatial characteristics of the rainfall medium by

using two earth stations to exploit the fact that the probability of attenuation due to

rain occurring simultaneously on the alternative Earth-space paths is significantly

less than the relevant probability occurring on either individual path. (Panagopoulos

et al., 2002).

Though the cost effectiveness of SD remains questionable, the interest on SD

has been renewed, due to the significant reduction of ground terminal antennas and

other hardware sizes. Nowadays, terminals can be installed in customers’ premises

and the use of public terrestrial networks to carry out signaling seems possible.

(Panagopoulos et al., 2002).

A rain-cell degrades the system performance at a part of the service area but

the rain can improve the carrier-to-interference ratio C/I conditions elsewhere

depending on the locations of the Base Station, Terminal Station and the rain-cell.

Interference fluctuation is a very important thing in LMDS network planning

procedures, which needs countermeasure techniques to avoid degradation of the

quality of service. (Sinka et al., 2002).

From the pervious paragraphs, it is clarified that the problem statement of this

project indicates that the high availability of LMDS can not be obtained under rain

effects, so site diversity should be suggested as one effective means to overcome rain

fading.

3

1.1 Objective of the Project:

The main objective of this project is to study the effects of site diversity in

LMDS under rainy conditions in Malaysia.

1.2 Scope of the Project

The scope of this project includes:

• To analyze the effects of a moving rain cell over an LMDS system

• This study includes calculation of Rain Attenuation in a given LMDS system.

1.3 Methodology of The Project

To carry out this project, the following methodology is designed as the following

steps:

• Establishing of LMDS Network:

By determining

- Frequency used and sectorisation

- Structure of system (BS & TS)

- Distance or cell size

• Calculation of Rain Attenuation based ITU-R Model by using Rainfall rate of

different locations over Malaysia in order to cover all Malaysia region

weather and therefore the study can be generalized to include the regions that

have the same climate (tropical climate weather).

4

• Analyzing of Rain cell Movement within LMDS, this is done by taking all

possibilities or terminal station situations over LMDS area and effect of

Interference signals.

• Site Diversity Implementation, this step is done according to the previous

studies related to LMDS system.

1.5 Thesis Outline

The layout of this report is as follows, chapter one includes a brief general

background of LMDS system and rain attenuation. The objective of this project is

clearly stated. The research scope and methodology are presented.

Chapter two is the first chapter of the literature review, presents the Local

Multipoint Distribution Service Systems and its specifications and components as

will as rain fading and its effects on the signal, also this chapter includes steps to

calculate rain attenuation.

Chapter three shows the concept of Site Diversity system and expressions

which are used to describe the performance of the site diversity. This chapter

explains brief details about how to implement site diversity in LMDS system during

rainy conditions and some parameters to express site diversity.

Chapter four represents the methodology of this project, including the

details of how to establish LMDS, rain attenuation calculation, effects of rain over

LMDS area and site diversity implementation are presented.

Chapter five presents the whole results of this work and discussions of these

results as well as some of analyses. The results include specific rain attenuation, rain

attenuation and different LMDS cell sizes with and without site diversity.

Comparisons and simulations of these results are also presented.

5

Chapter six contains summary, conclusion and the recommendations or future

work which are presented based on the obtained results.

REFERENCES

Agne Nordbotten, Telenor R&D (2000). LMDS Systems and their

Application. IEEE Communications Magazine June 2000.

Arapoglou, P. D. M., Kartsakli, E., Chatzarakis, G. E. and Cottis, P. G.

(2004). Cell-Site Diversity Performance of LMDS Systems Operating in

Heavy Rain Climatic Regions. International Journal of Infrared and

Millimeter Waves, 2004 – Springer.

Arapoglou, P. D. M., Panagopoulos, A. D., Kanellopoulos, J.D. and Cottis,

P.G. (2005). Intercell radio interference studies in CDMA based LMDS

network. IEEE Trans. Antennas Propag. vol. 53, no. 8, Aug. 2005.

Athanasios, D. Panagopoulos, Pantelis-Daniel M. Arapoglou, John D.

Kanellopoulos, and Panayotis G. Cottis. (2005). Long-Term Rain Attenuation

Probability and Site Diversity Gain Prediction Formulas. IEEE Transactions

on Antennas and Propagation, vol. 53, no. 7, July 2005.

Blake, R. (2001). Wireless Communication Technology. Wadsworth Inc.

Chu, C. and Chen, K. S. (2005). Effects of Rain Fading on the Efficiency of

the Ka-Band LMDS System in the Taiwan Area. IEEE Transactions on

Vehicular Technology, Vol. 54, NO. 1, January 2005.

88

Douglas A. Gary (1997). A Broadband Wireless Access System at 28 GHz.

IEEE, Wireless Communications Conference, Aug11-13, pp.1-7.

Enjamio, C., Vilar, E. and Fontán, F. P. (2002). Spatial Distribution of

Rainfall Rate: Benefits of the Site Diversity as a Dynamic Fade Mitigation

Technique. COST 280 PM3009 1st International Workshop 2002.

Falconer, D. D. and DeCruyenaere, J. P. (2003). Coverage Enhancement

Methods for LMDS. IEEE Communications Magazine, vol. 41, no. 7, pp. 86-

92, July.

Heder, B., Singliar, R., and Bito, J. (2005). Site Diversity Examination based

on Rain Attenuation Measurement. 47th International Symposium ELMAR,

08-10 June 2005, Zadar, Croatia.

Hendrantoro, G., Bultitude, R. J. C. and Falconer, D. D. (2002). Use of Cell-

Site Diversity in Millimeter-Wave Fixed Cellular Systems to Combat the

Effects of Rain Attenuation. IEEE JSAC, vol. 20, no. 3, Apr. 2002, pp. 602-14.

Hikmet Sari. (2000). “Trends and Challenges in Broadband Wireless Access.

0-7803-6684, IEEE, 2000.

ITU-R Recommendations (2005). Propagation data and prediction methods

required for the design of terrestrial line-of-sight systems. P.530-11.

ITU-R Recommendations (2005). Specific attenuation model for rain for

use in prediction methods. P.838-3.

Lee, C., Chung, B. and Lee, S. (1998). Dynamic Modulation Scheme In

Consideration of Cell Interference for LMDS. International Conference on

Communication Technology, ICCT'98 October 22-24, Beijing China, 1998.

89

Michael D. Lei. (2001). Factors Affecting Deployment Strategies for an

LMDS System in a Rural Commercial Environment. M.Eng. Thesis, Faculty

of the Virginia Polytechnic Institute and State University.

Panagopoulos, A. D. and Kanellopoulos, J. D. (2002). Cell-site diversity

performance of millimeter-wave fixed cellular systems operating at

frequencies above 20 GHz. IEEE Antennas Wirel. Propag. Lett., vol. 1, pp.

183-185.

Panagopoulos, A. D, Liolis, K. P. and Cottis, P. G. (2006). Cell-Site Diversity

Against Co-Channel Interference in LMDS Networks. Wireless Personal

Communications 39: 183–198, Springer.

Salem Salamah (2000). Transmit power control in fixed broadband wireless

systems”, M.Eng. Thesis, Carleton University Aug. 2000.

Sinka, C., Bito, J. (2003). Site diversity against rain fading in LMDS systems.

IEEE Microw. Wireless Comp. Lett., vol 13, no. 8, pp. 317-319, August

2003.

Sinka, C., Lakatos, B., Bitó, J. (2002). The Effects of Moving Rain Cell Over

LMDS Systems. COST Action 280, PM3027, 1st International Workshop

July 2002.

Standard Radio System Plan. (2003). Requirements for Local Multipoint

Communications Service (LMCS) Operating in the Frequency Bands From

24.25 GHz to 27.0 GHz, 27.0 GHz to 29.5 GHz and 31.00 GHz to 31.3 GHz.

Malaysia Communications and Multimedia Commission (MCMC SRSP)-

509, Issue 3.

The International Engineering Consortium (IEC). (2005). Local Multipoint

Distribution Service (LMDS). web proforum tutorials,

(www.iec.org.14/9/2006).

90

Zvanovec S., Pechac P. (2004). Site Diversity Time-Space Simulations for

LMDS. 0-7803-8521-7/04 IEEE.