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The method of frame synchronization in which the acquisition time is drastically reduced by using multi-component code is well known. There is a danger in this method, however, that large acquisition delays may occur in a low C/N environment due to errors of the partial correlation values. The purpose of this paper is to apply a multi-component code to acquisition in an effort to improve the performance of TDMA systems. The operation of the proposed acquisition method and the acquisition time performance in a low C/N environment are evaluated by experiment, theoretical analysis, and computer simulation and guidelines for acquisition system design to achieve fast and stable operation are proposed. The S/N value at the correlator output required for realizing the desired performance is determined. It is also shown here that performance can be improved greatly by providing a correlation detector with hysteresis. © 2005 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 88(5): 50–66, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.20157 [ABSTRACT FROM AUTHOR]

The conventional TDMA satellite communication system generally involves operations in which a sufficient amount of back-off is provided by using a large-scale high-power amplifier (HPA) in the earth station. However, if the HPA in the earth station can be operated at the saturation point, the earth station can be downsized and rendered into a low-power consumption station, with considerable benefits in terms of earth station installation and economy of operation. The authors have proposed a system combining an optimized transmission system and error-correction code, using burst modem filters and other devices, in a transmission system including two nonlinear devices of an earth station HPA and a satellite traveling-wave tube amplifier (TWTA), and have confirmed by computer simulations and experiments that it is feasible to operate the earth station HPA at its saturation point. The authors have also demonstrated that adequate performance characteristics can be attained in terms of burst-to-burst interference and cycle-skipping characteristics in the carrier recovery system. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(8): 47–62, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10149 [ABSTRACT FROM AUTHOR]