Final Report,
Abstract
After first listing and summarizing previous publications issued under this contract, this Final Report contains the following studies: (1) The basic factors in multipath, and some existing systems of reducing these defects, are examined together with conjectures on possible modifications of these systems to improve bandwidth-time utilization. (2) Results of capability calculations of two special classes of 2-3 channels, the complete erasure channel, and the fractional erasure channel, are presented. A slope method for 3-3 and 2-3 channels is also discussed. A mathematical analysis of the ambiguity function for three classes of waveforms, and a theorem on the unimodular linear transformation of the ambiguity plane, are presented. (4) Two novel schemes of detection, an a posteriori probability computer for a digital communication channel with memory, and an asynchronous demodulator for double-sideband (carrier suppressed) transmissions, are studied. (5) A theoretical comparison is made on the relative per-word reliabilities in a digital channel between the uncoded case and the case where an error-correcting code is used at the same energy and time-bandwidth per word. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- May 31, 1961
- Accession Number
- AD0264765
Entities
People
- J. Spencer Rochefort
- Sze-hou Chang
Organizations
- Northeastern University