Satellite communications system utilizing parallel concatenated coding

A VSAT communications system for communication via satellite, comprising:

• a plurality of VSAT terminals each comprising:
• a parallel concatenated encoder comprising a plurality of component encoders connected in a parallel concatenation, the parallel concatenated encoder applying a parallel concatenated code to a block of data bits received from a source and generating component codewords therefrom, the parallel concatenated encoder comprising a codeword formatter for formatting the bits of the component codewords to provide a composite codeword;
• a packet formatter for assembling data packets for transmission, each data packet comprising bits from at least one composite codeword;
• a modulator for receiving the data packets and providing modulated signals therefrom;
• an up-converter for translating modulated signals to a carrier frequency;
• an interface for connecting each respective VSAT terminal to an antenna for transmitting modulated signals to the satellite and receiving modulated signals from the satellite;
• a down-converter for translating each received signal from the carrier frequency to an intermediate frequency;
• a demodulator for synchronizing to and demodulating the received signals;
• a packet-to-codeword formatter for forming received composite codewords from the demodulated signals;
• and
• a composite decoder comprising a plurality of component decoders for decoding the received composite codewords.