Trellis constellation shaping

A system for reducing the average power of a constellation through reshaping, the system comprising:

• an input configured to receive two or more inputs bits;
• a filter configured to accept and process at least one of the two or more input bits to create two or more filtered bits, wherein the filter introduces at least one extra bit;
• an encoder configured to received and perform encoder processing on non-filtered input bits to create encoded bits;
• a buffer configured to receive the filtered bits and the encoded bits to create buffered bits;
• a decoder configured to receive and processes the filtered bits to create one or more decoded bits, wherein the processing by the decoder reduces average energy;
• one or more summing junctions configured to combine and output the decoded bits with the at least one of the buffered bits;
• a mapper configured to map the buffer output and the summing junctions outputs to a constellation point.