Adaptive time delay circuitry for interference cancellation systems
Abstract
The objective of this research program was to study and investigate variable time delay techniques for use in interference cancellation systems so as to improve their performance. A comprehensive survey of past research pertaining to HF, VHF, and UHF variable time delay techniques was undertaken. The survey also included microwave variable time delay techniques that are adaptable to the lower bands. As part of this program, variable delay lines were constructed and experimental measurements performed. Specifically, two types of delay lines were investigated, one using a coaxial transmission section with a helix surrounding a ferrite rod and the other a powdered ferrite and dielectric loaded coaxial section. The report presents experimental results over the HF, VHF, and UHF bands.
- Publication:
-
NASA STI/Recon Technical Report N
- Pub Date:
- April 1980
- Bibcode:
- 1980STIN...8030605C
- Keywords:
-
- Acoustic Delay Lines;
- Cancellation Circuits;
- Delay Circuits;
- Phase Shift Circuits;
- Radio Frequency Interference;
- Time Lag;
- Curves (Geometry);
- Duplex Operation;
- Electric Relays;
- Ferrites;
- Communications and Radar