초록 ▼

A two-way paging system includes a paging terminal and one or more transmitters and receivers. The paging terminal, transmitter and receiver are synchronized to a common clock reference which is derived from the global positioning satellite system. The transmitter transmits paging signals in sequent

A two-way paging system includes a paging terminal and one or more transmitters and receivers. The paging terminal, transmitter and receiver are synchronized to a common clock reference which is derived from the global positioning satellite system. The transmitter transmits paging signals in sequential frames having a predefined start time and duration. A paging unit is instructed to transmit its acknowledge signal during a predefined time slot. By synchronizing the paging terminal transmitters and receivers to a common clock the receivers are able to determine the frame number and time slot during which an acknowledge signal is transmitted based on the time of reception of the acknowledge signal. If the acknowledge signal is transmitted during the correct flame and time slot, the paging system can determine that the paging unit has received the paging message correctly.

대표청구항 ▼

A circuit for decoding a paging signal received on a reverse channel from a remotely located paging unit which was transmitted in response to a paging message transmitted on a forward channel from a paging transmitter, comprising: a register for storing a synchronize code; a correlator circuit that

A circuit for decoding a paging signal received on a reverse channel from a remotely located paging unit which was transmitted in response to a paging message transmitted on a forward channel from a paging transmitter, comprising: a register for storing a synchronize code; a correlator circuit that samples the paging signal received on the reverse channel and analyzes the sample to determine if the received paging signal matches the synchronize code; a timing circuit for providing an indication of the current time; means for storing an indication of the time at which a beginning of the paging signal was received; and means for updating the register with a new synchronize code based on the time since the paging signal was received and the current time.