Importance

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Abstract

A 'narrow band' public service trunking (PST) simulcast radio frequency transmission system having high-speed and low-speed digital data access capabilities in addition to analog voice operates in the 900 MHz frequency-range, as distinguished from a conventional 'wide band' PST system that operates in the 800 MHz frequency range. In a narrow band PST simulcast system having digital access capabilities, the handling of low speed digital data must be accomplished differently than high speed data since it becomes unique to each channel. This would ordinarily require providing an additional data path for each channel, or a wider band width audio path neither of which is feasible or cost effective. Arrangements are therefore provided for the routing of low-speed data to each transmit site via the high-speed digital data channel path for each site and for holding the high-speed data resynchronization circuitry at each site at its previous latency during the transmission of low-speed data, which would otherwise cause erroneous triggering of the resynchronization circuitry.

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First Claim