Patent ID: 6061408
Filing Date: 2000-05-09
Classification: H04L

Abstract:
A trellis encoder for 8PSK modulation of the type wherein input data bits are encoded to three-bit symbols, the encoder comprising:a first differential encoder having an input for receiving a first data bit of a set of input data bits;a convolutional encoder having an input connected to an output of the first differential encoder, and first and second convolutional encoder outputs; andfirst and second encoding assemblies, each encoding assembly comprising:a first multiplexer having a data input for receiving a pair of data bits of the set of input data bits, one of the pair of data bits preceding another of the pair of data bits in time, first and second select inputs respectively connected to the first and second convolutional encoder outputs, and a pair of outputs;a second differential encoder having an input connected to one of the first multiplexer outputs;a third differential encoder having an input connected to another one of the first multiplexer outputs;a second multiplexer having a pair of data inputs each respectively connected to a different one of the second and third differential encoder outputs, first and second select inputs respectively connected to the first and second convolutional encoder outputs, and an output.