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Issues in the development of a 10 MBPS K=15 Viterbi decoderThe NMSU Telemetry Center, in collaboration with the NASA Microelectronics Center (MRC) at UNM, has completed a study of the feasibility of building a constraint length 15, rate 1/2 Viterbi Decoder (or BVD) to operate at a rate of 10 Mbps. The BVD, if built, would make TDRSS more accessible to all users, small satellites in particular, by providing an additional 2 dB of link margin, relative to the use of the standard constraint length 7 decoder. The study included the following: review of the 1 Mbps BVD built by the Jet Propulsion Laboratory (JPL), currently the only BVD in existence; development of Specifications for the basic processing unit of the BVD (MRC); analytical Determination of performance of large constraint length convolutional codes; investigation of the impact of processor design on the overall system design; and two feasible packaging technologies, proposed by Cincinnati Electronics of Ohio. It was concluded that while the construction of the BVD is feasible, it will require the most advanced packaging technology currently available, and that the project would be best accomplished in an industrial facility. While the size, complexity, and power requirements of the BVD will be extreme, these will impact only the ground station. The spacecraft will incur a minor change in the encoder design, and the increased coding gain will allow a satellite to operate with a smaller antenna.
Document ID
19940030851
Acquisition Source
Legacy CDMS
Document Type
Contractor Report (CR)
Authors
Osborne, William P.
(New Mexico State Univ. Las Cruces, NM, United States)
Date Acquired
September 6, 2013
Publication Date
January 1, 1994
Subject Category
Space Communications, Spacecraft Communications, Command And Tracking
Report/Patent Number
NASA-CR-196083
NAS 1.26:196083
Accession Number
94N35357
Funding Number(s)
CONTRACT_GRANT: NAG5-1491
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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