Performance of convolutionally coded unbalanced QPSK systemsAn evaluation is presented of the performance of three representative convolutionally coded unbalanced quadri-phase-shift-keying (UQPSK) systems in the presence of noisy carrier reference and crosstalk. The use of a coded UQPSK system for transmitting two telemetry data streams with different rates and different powers has been proposed for the Venus Orbiting Imaging Radar mission. Analytical expressions for bit error rates in the presence of a noisy carrier phase reference are derived for three representative cases: (1) I and Q channels are coded independently; (2) I channel is coded, Q channel is uncoded; and (3) I and Q channels are coded by a common 1/2 code. For rate 1/2 convolutional codes, QPSK modulation can be used to reduce the bandwidth requirement.
Document ID
19820037060
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Divsalar, D. (Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Yuen, J. H. (California Institute of Technology, Jet Propulsion Laboratory, Pasadena CA, United States)
Date Acquired
August 10, 2013
Publication Date
January 1, 1980
Subject Category
Space Communications, Spacecraft Communications, Command And Tracking
Meeting Information
Meeting: In: NTC ''80; National Telecommunications Conference