Accession Number : ADA185474

Title :   An Analysis of Simplified Feed Architectures for MMIC (Monolithic Microwave Integrated Circuit) T/R (Transmit/Receive Module Arrays,

Corporate Author : ROME AIR DEVELOPMENT CENTER GRIFFISS AFB NY

Personal Author(s) : Poirier, J Leon

PDF Url : ADA185474

Report Date : Feb 1987

Pagination or Media Count : 31

Abstract : MMIC T/R modules offer the possibility for simplifying the feed networks of active aperture phased arrays. In particular, the addition of amplitude control along with the existing phase control would allow the same feed network to be used in the transmit and receive modes even though the two require grossly different aperture tapers. This is easily accomplished by using the amplitude control in the modules to provide the weighting required to produce low sidelobe receive beams. Specific examples in which amplitude control is implemented with digital attenuators are examined. The effect of the attenuators on the array output signal-to-noise ratio and the error sidelobe level due to the amplitude quantization are evaluated. The results indicate that the component values needed - total attenuation 20 to 30 dB, low noise amplifier gains and noise figures 20 to 30 dB and 3 to 4 dB respectively, and quantization of 2 to 6 bits - are readily achievable in current GaAs technology. With these, active aperture monopulse arrays with sidelobe levels of -20 to -50 dB below the peak of the mainbeam may be designed with greatly simplified feed networks. (Author)

Descriptors :   *ANTENNA FEEDS, *DIGITAL SYSTEMS, *LOW NOISE AMPLIFIERS, *MODULAR CONSTRUCTION, *MONOPULSE RADAR, *PHASED ARRAYS, AMPLITUDE, APERTURES, ARCHITECTURE, ARRAYS, ATTENUATORS, CONTROL, ERRORS, FEEDING, GALLIUM ARSENIDES, INTEGRATED CIRCUITS, MICROWAVE EQUIPMENT, MONOLITHIC STRUCTURES(ELECTRONICS), NETWORKS, OUTPUT, PHASE CONTROL, POWER LEVELS, QUANTIZATION, SIDELOBES, SIGNAL TO NOISE RATIO, SIMPLIFICATION

Subject Categories : Active & Passive Radar Detection & Equipment
      Electrical and Electronic Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE