Active Interference Cancellation System.
Abstract
The report reviews some of the principles and performance of an active Interference Cancellation System fabricated for UHF communication applications, and the techniques investigated and incorporated to increase the power handling capability of its signal controller. The system employs a synchronous cancellation technique for the suppression of receiver adjacent channel interference. The assigned task involved the investigation of techniques that would extend the power handling capability of the existing signal controller by employing more or alternate diodes, RM amplification, or alternate coupling devices to handle at least a +20 dBm interference signal at the receive antenna. Simultaneously with the above, the overall noise figure of the Interference Cancellation System will not degrade a receiver of -115 dBm sensitivity with a 50 kHz IF bandwidth. It was found that the best method for achieving the goal of +20 dBm was to employ alternate diodes and that higher power levels could be provided by employing more diodes and/or RF amplification. Still higher interference signal power levels can be cancelled by employing alternate coupling devices such as 10 or 20 dB summing couplers. The operational tradeoff for this option is that the apparent receiver sensitivity would decrease by 7 dB or 17 dB respectively. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1970
- Accession Number
- AD0864938
Entities
People
- David R. Martin
- Walter A. Sauter