Method and apparatus for encoding and decoding digital information

A coding system for error protecting digital information transmitted from a transmitter station and received at a receiver station, comprising:

• (a) a transmitter encoder in said transmitter station for coding an information block of said digital information, said transmitter encoder including:
• (1) an information encoder for coding an information block of said digital information to produce an information code word including an information vector and a primary redundancy vector;
• (2) a redundancy encoder for coding said primary redundancy vector to produce a redundancy code word including said primary redundancy vector and a secondary redundancy vector;
• (b) a receiver decoder in said receiver station for decoding a received information code word and for selectively erasing said received information code word, said receiver decoder including:
• (1) a primary information decoder for decoding said received information code word to produce an initial estimated information vector;
• (2) a redundancy decoder for decoding a received redundancy code word to produce an estimated primary redundancy vector;
• (3) a secondary information decoder for decoding an initial estimated code word including said initial estimated information vector and said estimated primary redundancy vector to produce a subsequent estimated code word;
• (4) a comparison test where said initial estimated code word and said subsequent estimated code word are compared;
• (5) wherein said receiver decoder selectively erases said received code word based on said comparison of said initial estimated code word and said subsequent estimated code word.

A coding method for error protecting digital information transmitted from a transmitter station and received at a receiver station, comprising:

• (a) coding an information block of said digital information at said transmitter station to produce an information code word including an information vector and a primary redundancy vector;
• (b) coding said primary redundancy vector to produce a redundancy code word including said primary redundancy vector and a secondary redundancy vector;
• (c) transmitting said information code word and said redundancy code word;
• (d) receiving said transmitted information code word and said transmitted redundancy code word at said receiver station;
• (e) decoding said received information code word to produce an initial estimated in formation vector;
• (f) decoding said received redundancy code word to produce an estimated primary redundancy vector;
• (g) decoding an initial estimated code word including said initial estimated information vector and said estimated primary redundancy vector to produce a subsequent estimated code word;
• (h) comparing said initial estimated code word and said subsequent estimated code word;
• (i) selectively erasing said received code word based on said comparison of said initial estimated code word and said subsequent estimated code word.

A coding system, comprising:

• (a) a transmitter encoder for coding an information block to produce an information code word including an information vector and a primary redundancy vector, and for coding said primary redundancy vector to produce a redundancy code word including said primary redundancy vector and a secondary redundancy vector;
• (b) a transmitter for transmitting said information code word and said redundancy code word;
• (c) a receiver for receiving said transmitted redundancy code word and information code word;
• (d) a receiver decoder for producing an initial estimated code word in response to said received information code word and a subsequent estimated code word in response to said received redundancy code word and said initial estimated code word, said receiver decoder comparing said initial estimated code word and said subsequent estimated code word and selectively erasing said receive code word based on said comparison of said initial estimated code word and said subsequent estimated code word.

A method for decoding a received codeword repeated at a receiver station through diversity means, wherein each repetition of the received codeword includes an information vector and redundancy vector, said method comprising:

• (a) inputting one or more of said information vectors in said received codewords to a series of parallel decoders;
• (b) inputting one or more of said redundancy vectors in said received codewords to said parallel decoders;
• (c) decoding the information vectors separately in said parallel decoders to generate a plurality of estimates of the information sequence;
• and
• (d) combining at least two estimates of the information sequence to generate a composite estimate.