Distress Buoy System Analysis.
Abstract
This report presents a brief analysis and comparison of two candidate approaches to the implementation of a multiple access Emergency Position Indicating Radio Beacon (EPIRB) system for maritime use. One approach uses frequency-shift-keyed (FSK) audio tone pairs for user identification, with detection employing a bank of narrow-band filters. False alarm probabilities and other parameters are calculated for this approach. An alternative to this approach, promising improved performance in the presence of multiple interfering EPIRBs, is also described. This alternative uses orthogonal Pseudo-Noise (PN) spread-spectrum sequences to identify each EPIRB uniquely. These sequences are easily generated using linear shift registers, and the resulting receiver structure is comparable in complexity with that needed for the FSK approach. It is concluded that the acquisition and detection performance of the two approaches is about equal, but that the spread-spectrum method has advantages in a multiple-access environment.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1978
- Accession Number
- ADA053676
Entities
People
- Howard C. Salwen