A frame including two error detection codes, one of the codes masking additional information such as a terminal identifier or Walsh code identifier

摘要

An initial error detection code is calculated for information which is to be transmitted in a frame across a wireless communication network using CDMA. The error detection code is then combined with one or more identifiers, such as a terminal identifier for the terminal which is to receive the frame or/and a Walsh code allocation (WCA) identifier, to produce a first error detection code. The frame contains the information, the first error detection code and a second error detection code which protects both the information and the first error detection code. This method allows additional information (i.e. the identifiers) to be implicitly transmitted, without adding overhead. Preferably the frame is transmitted on PDCCH control channel. The error detection codes may be generated using CRC. The combining operation may be performed using an Exclusive-OR operation, or by initialising CRC registers with identifier bits. The frame may also include tail bits.