CDMA Reference Blockset

IS-95A Walsh Code Generator

Generate the Walsh code sequences corresponding to the specified Walsh order and indices

Library

IS-95A Common

Description

This block generates the Walsh code sequences corresponding to the specified Walsh order and indices, according to the IS-95A specification. If W is the Walsh order parameter, then the block generates one of the 2^W sequences for each index specified in the parameters. Walsh code sequences have length 2^W and the different Walsh code sequences are mutually orthogonal. The Walsh code sequences corresponding to a Walsh order of 6 are given in a table in the IS-95A specification.

Outputs

Real vector of bipolar data representing the Walsh code sequences. The output size is an integer multiple of 2^W. The block outputs the Walsh code sequences of length 2^W in the order corresponding to the Walsh indices parameter. The output is a frame-based signal.

Dialog Box

Parameters

Walsh order

Integer scalar that specifies the Walsh code order. The output of the block consists of vector(s) of 2^W elements. The default value for IS-95A is 6.

Walsh indices

Integer vector that specifies the index or indices of the Walsh code sequences to be generated. If this parameter contains one index, then the output is a vector of length 2^W elements containing the Walsh code sequence of that index. If this parameter has length N, then the output is N concatenated vectors. Each output segment of length 2^W contains the Walsh code sequence for one of the indices given in the vector.

Sample time

Real scalar that specifies the block sample time.

See Also

IS-95A Fwd Ch Rake Finger
IS-95A Fwd Ch Detector
IS-95A Fwd Ch Base Station Transmitter Interface
IS-95A Forward Traffic Channel Detection Demo

Specification References

IS-95A 7.1.3.1.8
J-STD-008 3.1.3.1.8, 3.1.3.1.9

IS-95A Syndrome Detector