US 5,204,874 A · Method and apparatus for using orthogonal coding in a communication system

Abstract

A method and apparatus is provided for encoding and decoding. In encoding, bits (202) are encoded (204) into symbols (206) such that maximum likelihood decoding is facilitated. Groups of symbols (206) are translated by either interleaving by group each group within a block (208) and subsequently deriving an orthogonal code from each group (212) or deriving an orthogonal code from each group and subsequently interleaving by code each code within a block. In decoding, groups of samples (228, 229) are transformed by either generating metrics and index symbols (242) for each group of samples (232, 234, 236, 238, 240) and subsequently deinterleaving by group each group of metrics within a block (244) or deinterleaving by group each group of samples within a block and subsequently generating metrics and index symbols for each deinterleaved group of samples. Each metric represents the confidence that a group of samples is a particular orthogonal code. Subsequently, maximum likelihood decoding (266) generates an estimated bit (268) from the index symbols and metrics (260).

Claims25

Dependent claims

An apparatus comprising a signal encoder, the signal encoder comprising:

(a) encoding means for encoding input data bits of a signal into data symbols and grouping the data symbols, the data symbols being encoded with an encoding algorithm, wherein the encoding algorithm produces data symbols which are subsequently decoded into data signal bits using maximum likelihood decoding, the encoding algorithm comprising implementing at least one generator function having weight spectrum optimized for use in orthogonal coding;
and
(b) translating means, operatively coupled to the encoding means, for translating the groups of data symbols according to an algorithm selected from the group consisting essentially of (i) interleaving by group each group of data symbols within a predetermined size block and subsequently deriving an orthogonal code from each group of interleaved data symbols and (ii) deriving an orthogonal code from each group of data symbols and subsequently interleaving by orthogonal code each orthogonal code within a predetermined size block.

A method of convolutionally encoding data bits of a signal for transmission, comprising:

(a) convolutionally encoding input data bits of the signal into data symbols, the data symbols being encoded with an encoding algorithm such that the data symbols may be subsequently decoded into data signal bits with maximum likelihood decoding techniques, the encoding algorithm comprising implementing at least one generator function having weight spectrum optimized for use in orthogonal coding;
(b) grouping the data symbols;
(c) translating the groups of data symbols according to an algorithm selected from the group consisting essentially of (i) interleaving by group each group of data symbols within a predetermined size block and subsequently deriving an orthogonal code from each group of interleaved data symbols and (ii) deriving an orthogonal code from each group of data symbols and subsequently interleaving by orthogonal code each orthogonal code within a predetermined size block;
and
(d) transmitting the translated groups of data symbols over a communication channel.

2 more elements

Dependencies are inferred from the claim text.

Method and apparatus for using orthogonal coding in a communication system

Life of this patent

Method and apparatus for using orthogonal coding in a communication system

Life of this patent

Abstract

Claims25