Antimultipath Techniques for Packet Radio, III: The M'ary Case
Abstract
In previous Packet Radio Technical Notes (1), (2), we have restricted ourselves to consideration of antimultipath techniques for binary signaling. Even with such complex receivers, we have found that multipath-induced intersymbol interference takes a toll of several dB of transmitter power. In the present report, we analyze and simulate the performance of several Mary systems in the multipath environment, and compare them with those of binary system. The fundamental conclusion we come to is that we can do no better in urban/suburban multipath at high (1 Mbps) rates than by using the self-adaptive estimator/ correlator structure of that uses binary DPSK signalling and RAKE reception. The choice between, say 16'ary 'orthogonally' keyed RAKE and binary DPSK RAKE lies simply in the following issues: The estimator/correlator of for binary signalling (which must unscramble intersymbol interference) so much more complicated than the estimator/correlators for 16'ary signalling (which have no intersymbol interference to consider) is to outweigh the natural simplicity of binary transmitter and receiver. Radio communications.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 17, 1980
- Accession Number
- ADA214654
Entities
Organizations
- SRI International