Extensible Beamformer with Dynamic Focusing for 1.5D Sonar Arrays

Period of Performance: 03/16/1998 - 06/30/1999

$675K

Phase 2 SBIR

Recipient Firm

Q-dot, Inc.
1069 Elkton Drive
Colorado Springs, CO 80907
Principal Investigator

Research Topics

Abstract

Sonars for imaging used by divers, UUVs, AUV, and torpedoes are limited in their resolution by the size and power consumption of their receiver/beamformer electronics. For example, an actual 48-channel/71-beam stat-of-the-art sonar occupies 2600 in3 and dissipates 110 W. Increasing resolution by an order of magnitude at 54 in3/channel and 2.3 W/channel (37 in3/beam and 1.5 W/beam)is not feasible for small platforms. Q-Dot proposes a set of eight integrated circuit chips (ICs) which will form 512 beams from 512 channels while dissipating 7.2 W. Conventioal packaging will require about 64 in3 to house these chips. The result is a receiver/beamformer which occupies 1/8 in3 per channel (cr beam) that dissipates 17 mw per channel (or beam) including power conditioning. These ICs will utilize a combination of analog and digital signal processing. Front end chips comprise LNA, TGC (or TVG), apodizer, and AE modulators realized in bipolar technology. Extensible ID beamformer chips comprise dynamic focus, steering, demodulation, and interpolation realized in CMOS technolgy. Beams are formed with true time delays to produce wide bandwidth signals. 1D azimuthal beams are formed in elevation to 1.5D with a COTS DSP chip. Both the front-end chip and 1D beamformer chip will be designed and fabricated during the Phase II effort. During Phase III, these initial chips will be refined and integrated into a future sonar by our commercialization partner, SonTech, Inc.