Adaptive Beamforming for Submarine-Satellite Communications with the (MBCA) Multielement Buoyant Cable Array Antenna
Abstract
In order to provide the capability for submarines to communicate through a satellite while remaining submerged and traveling at operational speeds a towed buoyant cable array antenna is being developed. The array is adaptive from the point of view that the direction of the satellite need not be known, the position and orientation of the array need not be know, and the shape of the flexible array need not be known. A blind equalization procedure is used to estimate the signal space from the downlink signal and create a spatial matched filter for receive. While the frequency division satellite system is intended to allow only one signal per frequency slot, the system can also operate in the presence of jamming by separating multiple sources spatially. Once the downlink receive antenna weights have been obtained, the more difficult task of obtaining uplink weights at a separated frequency must be performed. Since no data is available for blind equalization at the transmit frequency a frequency extrapolation method is used to extend the downlink receive weights to frequencies beyond where the equalization data was collected. This extrapolation is complicated by 2-pi ambiguities of the measured phases as well as amplification of measurement errors in the extrapolation process. An algorithm has been developed that performs well.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2001
- Accession Number
- ADA404878
Entities
People
- Blair D. Carlson
Organizations
- Massachusetts Institute of Technology