Local oscillators for frequency agile systems
Abstract
The paper compares two kinds of solid state LOs (Local Oscillators) and describes their use in frequency agile radars with the help of block diagrams and graphs. The requirements of tuning curve linearity, rapid transient frequency response, no frequency drift and acceptable noise performance are imposed. The transistor oscillator is found to satisfy the above conditions better than the Gunn oscillator. Cleanliness of the varactor surface is instructed for the reduction of post tuning drift. LO FM noise problem is solved by replacing the antenna with a variable attenuator and a movable short. Application of LO to MTI operation is achieved by phase-locking it to a YIG-tuned, high-stability oscillator with sufficiently high Q and low noise. Similar units have also been developed for X- and Ku-Band.
- Publication:
-
Microwave Journal
- Pub Date:
- January 1977
- Bibcode:
- 1977MiJo...20...35W
- Keywords:
-
- Frequency Stability;
- Magnetrons;
- Microwave Oscillators;
- Phase Locked Systems;
- Radar Receivers;
- Tuning;
- Block Diagrams;
- Frequency Control;
- Gunn Diodes;
- Harmonic Oscillators;
- Systems Engineering;
- Electronics and Electrical Engineering