SMART ANTENNAS FOR WIRELESS COMMUNICATION

workablejeansΚινητά – Ασύρματες Τεχνολογίες

21 Νοε 2013 (πριν από 3 χρόνια και 8 μήνες)

50 εμφανίσεις

MIMO WIRELESS
COMMUNICATION SYSTEMS

Bhaskar D. Rao



University of California, San Diego

La Jolla, CA 92093
-
0407

Textbooks


Introduction to Space
-
Time Wireless
Communications, A. Paulraj, R. Nabar and D.
Gore, Cambridge University Press


Fundamentals of Wireless Communications,
D. Tse and P. Vishwanath


Space
-
Time Block Coding for Wireless
Communications, E. G. Larsson and P. Stoica


MIMO Wireless Communications, Edited by E.
Biglieri, R. Calderbank

.

Prerequistive Classes


Digital Communication (ECE 258A,B)


Channel Coding (ECE 259A,B)


Information Theory (ECE 255A)


Statistical Signal Processing (ECE 251A)


Array Processing (ECE 251D)


Estimation Theory (ECE 275A,B)

Prerequisites

Course Grading


Homeworks 40%


Theory and Matlab


Project 25%


Presentation on day of Finals


Exam 35%

Wireless Channel Characteristics


Fading:
Multiple Paths with different phases add
up at the receiver resulting in a random path gain


ISI
: Paths with different delays causing intersymbol
interference (Frequency Selective Channels)


CCI
: Co
-
Channel users create interference


Noise
: Thermal noise from electronics


Doppler
: Channel varies over time (mobility)


Bandwidth
: Bandwidth limited and so data rates
can grow only as log(1 + SNR)

Space
-
Time Processing for

Wireless Communications

Base station

Base station

Mobile

Mobile

Mobile

Mobile

Mobile

Goal:

Exploit the spatial dimension to improve capacity and


quality of network

Variants of Multiple Antenna Systems

Terminology

Benefits of Space
-
Time Processing


Increased Capacity


Improved Signal Quality


Increased Coverage


Lower Power Consumption


Higher Data Rates

These requirements are often conflicting.

Need balancing to maximize system performance

Technical Rationale


Spatial Diversity to Combat Fading


Spatial Signature for Interference
Suppression


Array Gain enables Lower Power
Consumption


Multiple Transmit Antennas provide Transmit
Diversity


Capacity Improvements using Spatial
Multiplexing

Scenarios


Base Station or Mobile


Receive versus Transmit Antennas


MIMO systems


Choice of Multiple Access Scheme
(CDMA or TDMA)


Microcell versus Macrocell


Mobility versus Fixed

Beamforming

Antenna Array
Interferer
Interferer
Interferer
Desired
User
Multi
-
Input Multi
-
Output System

Capacity of MIMO systems

Role of Diversity

Two Fading Channels combined to improve SNR: Diversity gain

Spatial Diversity to Combat Fading