Planar waveguide yields mm-wave monopulse comparators
Abstract
The miniature monopulse comparator assemblies are machined from small split blocks of aluminum 3.000 in. in diameter and 0.375 in. thick at 94 GHz; at 35 GHz, the dimensions are 3.500 in. and 0.750 in., respectively. A computerized milling machine ensures very close control of the machining tolerances. The feed distribution lines are designed on the top of the comparator block without introducing waveguide runs. This allows the four balanced output ports to be distributed from their wide separation inside the comparator to a small cluster for proper feedhorn excitation. It is noted that these signals are then coupled to a unique multimode scalar feed horn through a sensitive resonant cavity. The horn throat of this feed is circular and sufficiently large to accommodate the HE(11) mode for the sum and HE(01) and HE(21) for the difference modes. It is pointed out that miniature monopulse comparators for 35 and 94 GHz employ planar waveguide technology to give a performance that is equivalent to much larger designs.
- Publication:
-
Microwaves
- Pub Date:
- March 1984
- Bibcode:
- 1984MicWa..23...99S
- Keywords:
-
- Antenna Feeds;
- Comparator Circuits;
- Millimeter Waves;
- Monopulse Antennas;
- Strip Transmission Lines;
- Waveguides;
- Antenna Radiation Patterns;
- Far Fields;
- Horn Antennas;
- Integrated Circuits;
- Microwave Antennas;
- Miniaturization;
- Parabolic Reflectors;
- Planar Structures;
- Electronics and Electrical Engineering