Design and evaluation of antennae for ECE measurements on JET
Abstract
Antenna design principles for ECE measurements are outlined and two antennas for spatial scan ECE diagnostic on JET are described. The antenna design is based on diffraction optics of a rectangular horn operating in its fundamental mode. One antenna was optimized for measurements of the fundamental ECE harmonic in the o mode, the other for the second ECE harmonic in the e mode. Spatial resolution of copper prototypes, tested at frequencies from 70 to 130 GHz, is satisfactory. Polarization scrambling is 0.5 %, with transmission 85 %. Optimal spatial resolution is only achieved when the system is aligned to within + or - 5 deg.
- Publication:
-
NASA STI/Recon Technical Report N
- Pub Date:
- July 1982
- Bibcode:
- 1982STIN...8311402B
- Keywords:
-
- Antenna Design;
- Cyclotron Radiation;
- Plasma Diagnostics;
- Tokamak Devices;
- Alignment;
- Antenna Radiation Patterns;
- Horn Antennas;
- Polarization (Waves);
- Signal Distortion;
- Spatial Resolution;
- Communications and Radar