Next generation TDMA terminal for INTELSAT system users

This paper provides the technical description of a next generation (Model 520) traffic terminal under development at Hughes Network Systems, Inc. (HNS) for INTELSAT TDMA system users. The design of this terminal takes full advantage of our current TDMA terminal (Model 1020), which has been very popular with the INTELSAT and EUTELSAT system users for more than 10 years. Additional improvements in the Model 520 are provided by extensive use of VLSI circuits to reduce module counts. BER performance is substantially improved by using an advanced digital modem and optional R7/8 soft decision BCH decoder. A key innovation in the modem is ASIC implementation of the Viterbi and Viterbi (1983) techniques for carrier recovery. This technique provides fast acquisition time, improved tolerance for carrier frequency offsets, and lower implementation loss. The reduction in modules count provides higher reliability, lower equipment cost, simpler installation and maintenance, and reduced power consumption. Operation and maintenance of the TDMA terminals is extremely simplified by using a PC-based integrated monitor and control console (IMCC)