Adaptive Communications Techniques.
Abstract
New methods were developed that are applicable to HF that will measure in a fraction of a second multipath, Doppler, in-band noise, signal strength, and frequency selective noise. These methods, which were developed for modems employing FSK and quaternary DPSK modulation, use the transmitted data to measure the characteristics of the medium; no additional test signals are required. As an outgrowth of the Doppler sensing technique, a new way of Doppler tracking for quaternary DPSK modems was developed. The measurements devised under this program can be used to initiate adaptive responses that will improve system performance. Several of the adaptive responses examined appear attractive for this application. A simulation program for evaluating the sensing techniques and these adaptive responses is presented. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1969
- Accession Number
- AD0854654
Entities
People
- Albert G. Franco
- Kenneth Morgan
- Marshall Egstein