III
CONTENTS
1.
INTRODUCTION .................................................................................................... 1
1.1.
Evolution of wireless technology ................................................................... 1
1.2.
Objectives and scope of the research ............................................................. 2
1.3.
Research methodology ................................................................................... 3
2.
LONG TERM EVOLUTION ................................................................................... 4
2.1.
LTE requirements ........................................................................................... 4
2.2.
Evolved Packet System (EPS) ....................................................................... 5
2.2.1.
Logical elements of EPS .................................................................. 6
2.2.2.
Interfaces and Protocols ................................................................... 9
3.
LTE RADIO ACCESS TECHNOLOGY ............................................................... 11
3.1.
Introduction to OFDM ................................................................................. 11
3.2.
Single Carrier FDMA ................................................................................... 12
3.3.
Multiple Input Multiple Output (MIMO) ..................................................... 13
3.4.
Modulation techniques ................................................................................. 14
3.5.
LTE frame structure ..................................................................................... 14
4.
EPS MOBILITY MANAGEMENT (EMM) .......................................................... 16
4.1.
EPS connection procedure ........................................................................... 16
4.2.
IDLE state mobility management ................................................................ 17
4.2.1.
Public Land Mobile Network (PLMN) selection ........................... 17
4.2.2.
Cell selection .................................................................................. 17
4.2.3.
Cell re-selection ............................................................................. 18
4.2.4.
Location Management.................................................................... 19
4.3.
Handover ...................................................................................................... 20
4.3.1.
Intra-LTE handover ........................................................................ 20
4.3.2.
Inter RAT handover ....................................................................... 25
4.4.
Measurement events and triggers ................................................................. 25
5.
PERFORMANCE INDICATORS .......................................................................... 27
5.1.
Link adaptation ............................................................................................. 27
5.2.
Physical Cell Identity (PCI) ......................................................................... 28
5.3.
Reference Signal Received Power (RSRP) .................................................. 28
5.4.
Reference Signal Received Quality (RSRQ) ............................................... 28
5.5.
Signal to Interference-Noise Ratio (SINR) .................................................. 29
5.6.
Capacity of memoryless channels ................................................................ 30
5.7.
Received Signal Code Power (RSCP) .......................................................... 31
5.8.
Downlink throughput ................................................................................... 31
6.
RADIO COVERAGE AND LINK BUDGET ........................................................ 33
IV
6.1.
Free space model .......................................................................................... 33
6.2.
Okumura-Hata model ................................................................................... 34
6.3.
Link budget calculations .............................................................................. 34
6.3.1.
Cell edge SINR calculations .......................................................... 35
6.4.
Theoretical cell coverage calculations ......................................................... 36
7.
MEASUREMENTS AND ANALYSIS .................................................................. 38
7.1.
LTE 800 MHz coverage measurements ....................................................... 40
7.1.1.
Measurement setup ........................................................................ 40
7.1.2.
CQI and link adaptation ................................................................. 40
7.1.3.
RSRP coverage analysis................................................................. 44
7.1.4.
RSRQ coverage analysis ................................................................ 51
7.1.5.
SNR analysis .................................................................................. 53
7.1.6.
Downlink throughput analysis ....................................................... 56
7.2.
LTE 1800 MHz measurements and comparison .......................................... 60
7.2.1.
CQI and link adaptation comparison ............................................. 60
7.2.2.
RSRP comparison .......................................................................... 62
7.2.3.
RSRQ comparison.......................................................................... 66
7.2.4.
SNR comparison ............................................................................ 68
7.2.5.
Throughput comparison ................................................................. 70
7.3.
UMTS 900 comparison ................................................................................ 73
7.3.1.
RSRP vs. RSCP.............................................................................. 73
7.3.2.
Throughput comparison ................................................................. 74
8.
CONCLUSION AND DISCUSSION ..................................................................... 77
8.1.
Measurement analysis .................................................................................. 77
8.2.
Reliability and validity test .......................................................................... 78
8.3.
Limitations of the analysis ........................................................................... 78
8.4.
Moving ahead ............................................................................................... 78
REFERENCES ................................................................................................................ 80
APPENDIX ..................................................................................................................... 83