초록 ▼

An acknowledge back (ack-back) pager is provide for use in a paging system which includes a central station which transmits a group of message signals to a group of ack-back pagers which are addressed as a group. The users of the group of addressed ack-back pagers indicate a response to their respec

An acknowledge back (ack-back) pager is provide for use in a paging system which includes a central station which transmits a group of message signals to a group of ack-back pagers which are addressed as a group. The users of the group of addressed ack-back pagers indicate a response to their respective pagers thus providing ack-back data. The pagers in the group of addressed ack-back pagers then simultaneously transmit back to the central station their ack-back data on different frequency sub-bands, a different frequency sub-band being allocated to each of the pagers in the group. The invention provides apparatus for controlling the frequency of the selected sub-band with very high accuracy.

대표청구항 ▼

An acknowledge back pager for processing paging signals transmitted at a paging channel frequency of FRX from a central paging station, said pager comprising; a local oscillator oscillating at a frequency FLO to generate an FLO signal; first mixing means, coupled to said oscillator, for mixing said

An acknowledge back pager for processing paging signals transmitted at a paging channel frequency of FRX from a central paging station, said pager comprising; a local oscillator oscillating at a frequency FLO to generate an FLO signal; first mixing means, coupled to said oscillator, for mixing said paging signals with said FLO signal to generate a down-converted signal at a frequency FC; frequency determining means, coupled to said first mixing means, for determining the frequency FC of the down-converted signal; sub-band selection means for selecting one of a plurality of frequency sub-bands on which said pager is to transmit an acknowledge back signal, said selection means determining a selected sub-band and a frequency offset FD corresponding to said selected sub-band, said offset FD being with respect to the frequency FRX; memory means for storing the value of the frequency FRX; determining means for determining the value of N for the selected sub-band wherein N=(FRX-FC)/(FD+FC) dividing means, coupled to said determining means, for dividing the FLO signal by N to generate an FLO/N signal, and second mixing means, coupled to said dividing means and said oscillator means, for mixing said FLO signal with said FLO/N signal to generate a carrier signal for said acknowledge back signal.