| 摘要 |
An electronic paging system and method for transmitting paging signals over a broadcast network, such as a standard pre-existing commercial radio broadcast system, adds paging signals to a normal radio baseband signal for non-interferential co-transmission therewith over the existing standard radio broadcast transmission system. A telephone interface receives paging information via normal telephone lines. The paging information is used to pseudo-randomly frequency-hop a frequency-synthesized signal which is added to the baseband audio of a standard commercial radio signal. This composite signal is then used to modulate the standard commercial radio broadcast carrier in the normal manner. Mobile pagers, or "beepers," receive and selectively decode (i.e. pseudo-randomly frequency-dehop) the standard commercial broadcast signal to determine whether and which pager is being summoned, i.e. addressed. The respective addresses of the individual pagers within the system correspond to start addresses used in pseudo-random code generators within the pager transmitter and each pager receiver.
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