Method and apparatus for packet transmission using CRC and equal length packets

摘要

The PDCAB packet (300) and the RRA packet (308) are transmitted together on the F-SCCH. For example, 9 RRA bits (305) are appended to the PDCAB field (303), in place of the pad bits (205), thereby allowing both the PDCAB (303) and RRA (311) messages to be protected against errors by a 16-bit CRC (307). In accordance with the embodiments, a receiver is able to distinguish between the varying PDCAB (303) and RRA (305) message formats and transmitting the packets (300) and (308) together is a normal mode of operation in the embodiments. Therefore, in accordance with the embodiments, when the PDCAB packet (300) and RRA packet (308) are transmitted together, the network replaces the N PDCAB pad bits, such as pad bits (205), with the first N bits from the RRA bitmap (311), in order to use the nominal CRC length for both packets (300) and (308).