UNIVERSITY OF CALGARY Concurrent Dual Band Six Port Receiver by Abdullah Oluwatosin ...

92 Pages·2014·3.85 MB·English

UNIVERSITY OF CALGARY

Concurrent Dual Band Six Port Receiver

by

Abdullah Oluwatosin Olopade

A THESIS
SUBMITTED TO THE FACULTY OF GRADUATE STUDIES
IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE
DEGREE OF MASTER OF SCIENCE

DEPARTMENT OF ELECTRICAL AND COMPUTER ENGINEERING
CALGARY, ALBERTA
JANUARY, 2014

© Abdullah Oluwatosin Olopade 2014
Abstract
Receiver front-ends have always been a critical component in wireless communication system
design. Its performance and characteristics determines the quality and fidelity of the
communication systems. Proliferation of communication protocols and standards however,
require that the front-ends should become more flexible, multi-standard and reconfigurable. In
addition, to enable higher communication throughput, there have been proponents of concurrent
dual-band receiver front-ends to receive signals in more than one band simultaneously. Typical
architecture for this concurrent multiband operation uses the front-end stack-up technique, which
builds parallel receiver paths with each path dedicated to one frequency band. This increases
complexity, power requirement, size and cost. The Six-Port receiver (SPR) is a low power and
low complexity alternative to conventional homodyne receiver, which is multi-standard, flexible
and easily reconfigurable. This thesis proposes the use of the SPR for a concurrent dual-band
operation without any component duplication in the frequency down-conversion path.
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Acknowledgements
All thanks and praises is due to almighty Allah; the creator, sustainer and lord of the worlds.
May his peace and blessings be upon the holy prophet Mohammed (SAW).
My sincerest gratitude to goes my supervisor, Dr. Mohamed Helauoi, and Prof Fadhel
Ghannouchi for giving me the opportunity to carry out this research work in their lab considering
I started my Master’s Degree program as a course based student. I really appreciate their
guidance, encouragement and support which has been very important in the success of my
research.
I would like to thank the other committee members Dr. Leonid Belostotski and Dr. Reda S.
Elhajj for their time in evaluating this work.
I would also like to take this opportunity to appreciate all members of the iRadio lab, the setting
and atmosphere has been a very friendly and productive one. Special thanks to Abul Hasan,
Andrew Kwan for the countless times of helping with the lab equipment, Ramzi Darraji for his
valuable advice and the soccer games and Ivana D’Adamo, the administrative support staff. This
page won’t be enough if I were to list everybody, you guys rock!
Last but not least, I would like to thank my parents, my brother and sister for their support and
encouragement, God knows I really needed it.

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To my parents…

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Table of Contents
Abstract .......................................................................................................................... ii
Acknowledgements ........................................................................................................ iii
Table of Contents ............................................................................................................ v
List of Tables ................................................................................................................ vii
List of Figures and Illustrations .................................................................................... viii
CHAPTER ONE: INTRODUCTION .............................................................................. 1
1.1 Modern Receiver Architectures ............................................................................. 4
1.1.1 Superheterodyne Receiver (SHR) .................................................................. 5
1.1.2 Direct Conversion Receivers (DCR) .............................................................. 6
1.1.3 Low-IF Receivers (LIF)................................................................................. 8
1.1.4 Subsampling Receiver ................................................................................... 9
1.1.5 Six Port Receiver (SPR) .............................................................................. 10
1.2 Receiver Architecture Comparison ...................................................................... 12
1.3 Concurrent Multiband Receivers ......................................................................... 14
1.4 Thesis Contribution ............................................................................................. 17
1.5 Thesis Outline ..................................................................................................... 19
1.6 Conclusion .......................................................................................................... 19
CHAPTER TWO: SINGLE BAND SIX PORT RECEIVER (SPR) ............................... 21
2.1 Introduction ......................................................................................................... 21
2.2 Structure of a Six Port Receiver. .......................................................................... 21
2.3 Theory of the SPR ............................................................................................... 24
2.4 Limitations of the SPR ........................................................................................ 27
2.5 SPR Calibration ................................................................................................... 28
2.5.1 Direct Linear Calibration ............................................................................. 29
2.5.2 Memory Polynomial Calibration.................................................................. 30
2.5.3 Least Square Technique............................................................................... 31
2.6 Conclusion .......................................................................................................... 32
CHAPTER THREE: PERFORMANCE ANALYSIS OF A SIX PORT RECEIVER IN A
WCDMA COMMUNICATION SYSTEM INCLUDING A MULTI-PATH FADING
CHANNEL .......................................................................................................... 34
3.1 Introduction ......................................................................................................... 34
3.2 Multipath Fading ................................................................................................. 35
3.2.1 Rician Channel ............................................................................................ 36
3.2.2 Rayleigh Channel ........................................................................................ 36
3.3 Six-port receiver in a WCDMA DL communication System ................................ 37
3.3.1 SPR Front-End Implementation. .................................................................. 39
3.3.2 Receiver Calibration .................................................................................... 40
3.4 MEASUREMENT RESULTS ............................................................................. 41
3.5 4G LTE System ................................................................................................... 44
3.6 CONCLUSION ................................................................................................... 46
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CHAPTER FOUR: CONCURRENT DUAL-BAND SIX-PORT RECEIVER FOR MULTI-
STANDARD AND SOFTWARE DEFINED RADIO APPLICATIONS .............. 47
4.1 Introduction ......................................................................................................... 47
4.2 Modern Dual-band Receivers Architectures ......................................................... 47
4.3 Concurrent Dual-band and multi-standard SPR.................................................... 50
4.4 Receiver Calibration ............................................................................................ 56
4.5 Concurrent Dual-Band and Multi-Standard SPR Implementation ......................... 58
4.6 Measurement Results........................................................................................... 59
4.7 Conclusion .......................................................................................................... 67
CHAPTER FIVE: CONCLUSION ................................................................................ 69
5.1 Research Summary .............................................................................................. 69
5.2 Comparison between the Concurrent Dual-band SPR and State-of -the-art receives72
5.3 Future Works....................................................................................................... 73
APPENDIX .................................................................................................................. 75
REFERENCES ............................................................................................................. 78

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List of Tables
TABLE 3.1: WCDMA end-to-end physical layer Subsystems ................................................... 37
TABLE 3.2: Estimated EVMs of receiver FE at all SNRs ......................................................... 43
TABLE 3.3 Summary of performance LTE based communication system ................................. 46
TABLE 4.1: Summary of performance for the demodulation process of 64 QAM and 16
QAM signal ....................................................................................................................... 63
TABLE 4.2: Summary of performance for the demodulation process of a WCDMA and LTE
signal ................................................................................................................................. 65
TABLE 5.1: Summary of performance for the demodulation process of 64 QAM and 16
QAM signal ....................................................................................................................... 71
TABLE 5.2: Summary of performance for the demodulation process of a WCDMA and LTE
signal ................................................................................................................................. 72

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List of Figures and Illustrations
Figure 1.1 SDR transmitter and receiver ......................................................................................2
Figure 1.2 Realizable implementation of a SDR receiver. ............................................................4
Figure 1.3 Superheterodyne Receiver ..........................................................................................5
Figure 1.4 Direct Conversion Receiver ........................................................................................7
Figure 1.5 Low IF Receiver .........................................................................................................9
Figure 1.6 Subsampling receiver ............................................................................................... 10
Figure 1.7 Six Port Receiver...................................................................................................... 11
Figure 1.8 Front-end stack-up technique in Multiband Receiver Design .................................... 15
Figure 1.9 Evolution of dual-band receivers from single-band receivers .................................... 16
Figure 2.1 a symmetrical five port ring junction and a directional coupler based six port wave
correlator ........................................................................................................................... 22
Figure 2.2 Wilkinson divider and directional couplers based six port wave correlator ................ 23
Figure 2.3 Typical Six Port Receiver Architecture ..................................................................... 25
Figure 2.4 Typical Six Port Receiver Architecture ..................................................................... 29
Figure 3.1 Multipath Channel. ................................................................................................... 35
Figure 3.2 MATLAB Simulink WCDMA end-to-end physical layer demo ................................ 38
Figure 3.3 Test bench set-up for the SPR Front End. ................................................................. 40
Figure 3.4 BER plot of the communication system. ................................................................... 44
Figure 3.5 Test bench set-up for the SPR Front End using transmitting and receiving
antennas ............................................................................................................................ 45
Figure 4.1: Front-end Stack-up concurrent dual-band receiver ................................................... 48
Figure 4.2 Evolution of dual-band receivers from single-band receivers. ................................... 49
Figure 4.4 Concurrent dual-band six-port receiver architecture. ................................................ 51
Figure 4.5. Schematic diagram of the DSP block of proposed dual-band architecture. .............. 51
Figure 4.6 Illustration of the LO frequency selection of proposed dual-band SPR ..................... 52
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Figure 4.7 Test bench set-up for the concurrent dual-band SPR. ................................................ 59
Figure 4.8 Diode Output Frequency Spectrum. .......................................................................... 61
Figure 4.9 Window of 16QAM Transmit and Received Signal (a) Constellation Plot; ............... 61
Figure 4.10 64QAM Transmitted and Received Signals (a) Constellation Plot; ......................... 62
Figure 4.11 BER plot for 16 QAM at 2Mbps. ............................................................................ 64
Figure 4.12 BER plot for 64 QAM at 2Mbps. ............................................................................ 64
Figure 4.13 WCDMA Transmit and Received Signal Frequency Spectrum ............................... 66
Figure 4.14 LTE Transmit and Received Frequency Signal Spectrum ....................................... 67

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List of Symbols, Abbreviations and Nomenclature
Symbol Definition
3G Third Generation
4G Fourth Generation
ADC Analog To Digital Converter
AGC Automatic Gain Control
AWGN Additive White Gaussian Noise
BB Baseband
BER Bit Error Rate
BPF Band Pass Filter
BS Base Station
BW Bandwidth
DAC digital to analog converter
DB Dual band
DBA Dual-band Antenna
DC Direct Current
DCR Direct Conversion Receivers
DL Downlink
DSP Digital Signal Processing
EVM Error vector Magnitude
FDD Frequency Division Duplex
FE Front-end
GPS Global Positioning System
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