Abstract: A communications system has a high altitude communication device generates a plurality of user link beams having a first communication characteristic and a feeder link having a first communication characteristic. A gateway terminal receives the user link beam for receiving a first received signal and a second received signal thereafter. The receiver circuit has a recursive filter for generating differential amplitude of symbol timing estimate from said first received signal.

Abstract: An improved method and system for estimating the signal to noise ratio in a communications system is provided. An FEC coded signal is received and demodulated. The signal is decoded, resulting in FEC coding gain. The decoded signal is re-encoded, and the re-encoded signal is used by the signal to noise ratio estimator to estimate the signal to noise ratio, thereby taking advantage of the FEC coding gain.

Abstract: A system and method of soft decision decoding is disclosed. An average signal magnitude is generated from a plurality of message bits. A scale factor is generated in accordance with the average signal magnitude, and soft decision bits are generated by processing the message bits using the scale factor. The scale factor and soft decision bits are transmitted and received across a communication link. The soft decision bits are rescaled using the scale factor and then rounded to the nearest integer value. The rounded values are then decoded. The soft decision bits are generated using a quantization having at least two bits, and soft decision bits are preferably rescaled using at least five bits.

Abstract: A method of channel estimation in a wireless communication system has steps of receiving a data burst comprising a plurality of portions of known data, and remaining data that is unknown; comparing reference data to each of the plurality of portions of known data and determining error for each of the portions of known data; averaging the determined error for predetermined ones of the portions of known data; and estimating error for at least a portion of the remaining data as a function of the determined error having been averaged.