Note:

ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / The Viterbi algorithm has uses for both the decoding of convolutional codes and the detection of signals distorted by intersymbol interference (ISI). The operation of these processes is characterized by a trellis. An ARTM Tier-1 space-time coded telemetry receiver required the use of an irregular Viterbi trellis decoder to solve the dual antenna problem. The nature of the solution requires the trellis to deviate from conventional trellis structure and become time-varying. This paper explores the architectural challenges of such a trellis and presents a solution using a modified systolic array allowing the trellis to be realized in hardware.

ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada / Current IRIG standards provide guidelines for system phase noise and several manufactures provide receivers and transmitters that perform within this standard. However, legacy receivers and transmitters that do not meet the current IRIG standards are sometimes still used during a mission. This paper will address how phase noise outside of the current IRIG standard affects the performance of an FM data link when using a trellis demodulator, as well as the performance of an SOQPSK data link in a high phase noise environment. Bit error rate performance and test results at several different rates with various phase noise masks are presented in this paper.

No description available.

Thesis (Ph.D.)--City University of Hong Kong, 2009. / "Submitted to Department of Electronic Engineering in partial fulfillment of the requirements for the degree of Doctor of Philosophy." Includes bibliographical references (leaves [142]-152)

Thesis (M.S.)--University of Texas at Dallas, 2007. / Includes vita. Includes bibliographical references (leaves 84-85)

International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Shaped Offset QPSK (SOQPSK), as proposed and analyzed by Terrance Hill, is a family of constant envelope waveforms that is non-proprietary and exhibits excellent spectral containment and detection efficiency. Results using a conventional coherent OQPSK demodulator without any special pulse shaping to recover the SOQPSK signal have been previously presented. This paper describes a trellis detector for SOQPSK-A and SOQPSK-B that provides superior detection performance, as compared to a traditional OQPSK detector, by accounting for the pulse shaping. Analytical error performance bounds, implementation of the trellis demodulator, and computer simulation results are presented.

International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / The Advanced Range Telemetry (ARTM) program is a tri-service telemetry modernization project whose goal is to assure that all Department of Defense (DoD) test and training ranges are able to use telemetry as necessary to carry out their respective missions. Multi-h Continuous Phase Modulation (CPM) has been selected by the ARTM JPO as the Tier II ARTM waveform, because it offers significant improvements over both legacy telemetry waveforms (PCM/FM) and the newly-introduced Tier I waveform (Feher-patented FQPSK) in terms of spectral containment and detection efficiency, while retaining a constant envelope characteristic. The paper describes the theoretical and measured performance of the ARTM Tier II multi-h CPM waveform, and the implementation of the trellis demodulator being developed for it.

No description available.

Due to constraints on spectrum availability and transmitter power, both bandwidth and power efficient communication techniques are desirable for mobile radio. Continuous phase modulated (CPM) signals have gained attention because of their attractive power spectra (Steele, 1992). It has been shown that the trellis coded modulation (TCM) schemes could provide better bit error rate performances compared to the uncoded schemes (Ungerboeck, 1982). Therefore, the combination of TCM which improves error probability and CPM signals which yield low spectral occupancy is expected to provide good coding and modulation over bandwidth and power limited channels such as the one encountered in mobile radio communications.In this research, a Trellis Coded Modulation (TCM) scheme, which combines convolutional coding and partial response Continuous Phase Modulation (CPM) such as Gaussian Minimum Shift Keying (GMSK), is investigated. Also, this study concentrates on the use of rate-half convolutional codes, and GMSK (B(subscript)0T=0.3). The latter has been adopted in the Global System for Mobile Communications (GSM) system.Appropriate codes are selected assuming Maximum Likelihood Sequence Detection (MLSD) based on the Viterbi algorithm using an extensive computer search. The bit-error-rate (BER) performances of the selected trellis coded GMSK schemes are theoretically evaluated in the presence of additive white Gaussian noise (AWGN) and frequency-flat fading. In the case of fading, the analysis is simplified to assume only amplitude-fading, and without considering the effect of fading on the phase of the received signal.Computer simulations are used to evaluate the BER performances of the proposed trellis coded GMSK schemes in the presence of AWGN and practical impairments, such as sample timing offset and carrier phase errors. Coding gains of up to 2.2dB at a BER of 10(subscript)-3 ++ / are obtained under ideal sample timing and carrier recovery conditions. This has been achieved without increasing the receiver complexity based on the number of states in the Viterbi decoder, compared to the uncoded GMSK scheme. Furthermore, these coded schemes are more tolerant to sample timing and carrier phase impairments.Also, the BER performances of the proposed trellis coded GMSK schemes have been extensively investigated by computer simulations for frequency-flat and frequency-selective fading channels. In the case of frequency-selective fading, the Viterbi decoding is made adaptive to cater for the channel impulse response variations with time. With this adaptive receiver, the irreducible BERs of the coded scheme is found to be lower than that of the uncoded. Performance improvements are obtained with a trellis coded GMSK scheme using a constraint length 2 code with a Viterbi decoder of 16 states compared to the 128 states required for the uncoded scheme. Further, the coded scheme has shown less sensitivity to carrier phase errors, compared to the uncoded.