METHOD OF LENGTHY MESSAGE TRANSMISSION COMPATIBLE WITH PRESENT POCSAG SYSTEM
Original Publication Date: 1991-Dec-01
Included in the Prior Art Database: 2001-Dec-26
The POCSAG paging format uses a block code for error correction. Block codes, however, do not perform well in RF Iiis characterized by Rayleigh fading. While the (31,21) BCH code used in POCSAG is double error correcting, and is therefore good for correcting random errors, it is insufficient for channels characterized by burst noise,.where the errors tend to be grouped together. For the transmission of large messages, such as computer files, fax, or other large amounts of data, a more robust burst-error-protected encoding scheme is needed. Such a system must be compatible with existing subscriber equipment and not require rework of existing pages in the field. hi addition, it must be able to accept messages of arbitrary length. The encoding method outlined below meets these requirements using interleaving by batches; as a bonus it conserves pager battery life.