RESEARCH IN MULTIPLE ALTERNATIVE COMMUNICATIONS.
Final rept., 1 May 64-31 Oct 66,
LITTON SYSTEMS INC WALTHAM MASS SIGNAL PROCESSING DEPT
Pagination or Media Count:
A generic digital communication method, called q-M-ary transmission, is introduced and evaluated under the conditions of phase coherent and two types of phase incoherent reception of signals transmitted through a non-fading medium. The basic feature of this method is the use of M-ary transmission alphabets employing only q different waveforms to synthesize the transmitted signals. Special attention is directed to the effect of bandwidth constraints on the performance attainable with this method, and to the value of high-order M-ary transmission alphabets, when implemented with this method. Comparison of a particular form of this methodq2 with conventional binary coding indicates that at least a few dB improvement is provided by the 2-M-ary method with M large, even when bandwidth is severely limited. One of the types of phase incoherent operating modes is found to produce very nearly the same performance as that achievable with optimum phase coherent operation, when the transmission alphabet is large. Author
- Non-Radio Communications