Document Type

Thesis

Date of Award

9-30-1986

Degree Name

Master of Science in Electrical Engineering - (M.S.)

Department

Electrical Engineering

First Advisor

Joseph Frank

Second Advisor

Stanley S. Reisman

Abstract

Multi-h CPM, a generalization of CPFSK and also one of the so-called Combined Modulation and Coding schemes, is useful in digital communication systems where both the bandwidth and power are constrained. The increased signal processing complexity, which can be viewed as the third communication resource, is used to trade for both power and bandwidth, and to approach the error-free communication promised by Shannon's theorem.

The transmitted multi-h CPM signal carries a coded sequence of continuous phase changes; the possible phase states form a cylindrical trellis in phase and time, in which the modulation indices are reused in a cyclical fashion. The trellis diagram, minimum Euclidean distance between symbols, error rate and bounds, and power spectral density are investigated. Comparisons with other basic digital communication techniques are also examined. Simple codes using 4-16 phases, together with a Viterbi Algorithm decoder, allow a 2-4 dB power savings over BPSK with a narrower bandwidth. Four-ary 2-h schemes are found to have the best trade-off between complexity and coding gain. The free distance and decision depth are also determined. Finally, Viterbi Algorithm applied in the detection of a received AWGN-corrupted multi-h CPM signal is studied.

Share

COinS
 
 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.