DATA TRANSMISSION INVESTIGATION
Abstract
Field test results of various modems operating over the AN/VRC-12 radio set are presented. Map profiles of each data link are shown and the average error rates are given for digital data transmission at rates from 300 to 4800 bps. Bit error rates vary depending upon the site and bit rate. The errors are analyzed for multiple error characteristics and the probability of receiving a message error free as a function of message length. Photographs of the frequency spectra generated by each modem at their various bit rates are presented and used to discuss the relative bandwidth requirements of the modems. The performance of the FSK (AN/TYC-1,XC-2), Di Phase and Quad-phase modems in the presence of a controlled impulse moise test while operating at 1200 bps is shown in graphical form. A multi-frequency modem is being constructed for the HF data transmission study phase of the contract. The modem will have the capability of 18 bit rates and will be used in the investigation of the short range HF data transmission. System block diagrams of the multi-frequency modem are presented, and the performance of the clock genera tor and clock recovery circuits is discussed. The limits of the code's error correcting and detecting capability are shown, and the code's performance when these capabilities are exceeded is discussed.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 10, 1963
- Accession Number
- AD0417754
Entities
People
- R. F. Salava
Organizations
- Motorola Mobility