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Linscott, I.

Publications and source records attributed to Linscott, I..

The Mars Relay

The UHF Mars Relay onboard the orbiting Mars Global Surveyor spacecraft provides data relay capability for landed systems on Mars.

Mars Mars Global Surveyor spacecraft UHF Mars Rela

Ultranarrowband searches for extraterrestrial intelligence with dedicated signal-processing hardware

An evaluation is made of the prospects for SETI applications of multichannel spectroscopy, assuming narrowband RF beacon transmission, with a mHz resolution that matches interstellar medium properties. Receiver Doppler corrections must furnish substantial interference rejection. Results are presented from an Arecibo antenna search of 250 sunlike stars at 1.4 and 2.8 GHz. A meridian transit search of the northern sky is also in progress with the Harvard-Smithsonian 26-m antenna.

Horowitz, P.

Stanford Hardware Development Program

Architectures for high performance, digital signal processing, particularly for high resolution, wide band spectrum analysis were developed. These developments are intended to provide instrumentation for NASA's Search for Extraterrestrial Intelligence (SETI) program. The real time signal processing is both formal and experimental. The efficient organization and optimal scheduling of signal processing algorithms were investigated. The work is complemented by efforts in processor architecture design and implementation. A high resolution, multichannel spectrometer that incorporates special purpose microcoded signal processors is being tested. A general purpose signal processor for the data from the multichannel spectrometer was designed to function as the processing element in a highly concurrent machine. The processor performance required for the spectrometer is in the range of 1000 to 10,000 million instructions per second (MIPS). Multiple node processor configurations, where each node performs at 100 MIPS, are sought. The nodes are microprogrammable and are interconnected through a network with high bandwidth for neighboring nodes, and medium bandwidth for nodes at larger distance. The implementation of both the current mutlichannel spectrometer and the signal processor as Very Large Scale Integration CMOS chip sets was commenced.

Peterson, A.