资料介绍
communication circuits and systems performance measures of wireless communication6.976 High Speed Communication Circuits and Systems Lecture 20 Performance Measures of Wireless Communication
Michael Perrott Massachusetts Institute of Technology
Copyright 2003 by Michael H. Perrott
Recall Digital Modulation for Wireless Link
Baseband Input
it(t) Lowpass ir(t)
Receiver Output
t
2cos(2πf1t) 2sin(2πf1t) qt(t)
2cos(2πf1t) 2sin(2πf1t) Lowpass
t
qr(t)
t
Decision Boundaries
t Sample Times
- Spectral efficiency (transmitter) - Bit error rate performance (receiver) Nonidealities - Intersymbol interference - Noise Interferers M.H. Perrott
Send discrete-leveled values on I and Q channels Performance issues
MIT OCW
Impact of Receiver Noise
Baseband Input
it(t) Input-referred Receiver Noise
Receiver Output
Lowpass ir(t)
t
2cos(2πf1t) 2sin(2πf1t) qt(t)
2cos(2