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公开(公告)号：AT104491T
公开(公告)日：1994-04-15
申请号：AT88901685
申请日：1988-01-11
Applicant: MOTOROLA INC
Inventor： STEEL FRANCIS ROBERT , LEITCH CLIFFORD DANA , SUAREZ JOSE IGNACIO
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公开(公告)号：AT126638T
公开(公告)日：1995-09-15
申请号：AT89906916
申请日：1989-05-22
Applicant: MOTOROLA INC
Inventor： LEITCH CLIFFORD D , STEEL FRANCIS ROBERT
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公开(公告)号：AU2940289A
公开(公告)日：1989-08-01
申请号：AU2940289
申请日：1989-12-13
Applicant: MOTOROLA INC
Inventor： SIWIAK KAZIMIERZ , JASINSKI LEON , STEEL FRANCIS ROBERT
Abstract: An acknowledge back (ack-back) paging system is provided 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.
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公开(公告)号：AU2944589A
公开(公告)日：1989-08-01
申请号：AU2944589
申请日：1989-12-12
Applicant: MOTOROLA INC
Inventor： SIWIAK KAZIMIERZ , KEBA JAMES M , STEEL FRANCIS ROBERT
Abstract: An acknowledge back (ack-back) pager is provided for use in a paging system including 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. To accurately control the ack-back transmit frequency, the pager receives and down-converts the FRX signal thus producing a down-converted FC signal, the frequency of which is measured and stored. The pager selects which sub-band of a plurality of frequency sub-bands within a predetermined range of frequencies is to be used for transmission of the ack-back signal. The pager determines a frequency offset FD corresponding to the selected sub-band, such offset being with respect to a predetermined frequency within such range of frequencies. The pager generates an acknowledge back signal at a frequency (FC+FD)-FCTX and up-converts such signal to a transmit frequency FTX corresponding to said selected sub-band, FCTX being the frequency of a down-converted sample of the FTX signal.
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公开(公告)号：DE2719530A1
公开(公告)日：1977-11-24
申请号：DE2719530
申请日：1977-05-02
Applicant: MOTOROLA INC
Inventor： HODGES III EUGENE WALTON , STEEL FRANCIS ROBERT , ENDERBY RALPH THOMAS
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Patent Agency Ranking
公开(公告)号：HK119797A
公开(公告)日：1997-09-05
申请号：HK119797
申请日：1997-06-26
Applicant: MOTOROLA INC
Inventor： SIWIAK KAZIMIERZ , JASINSKI LEON , STEEL FRANCIS ROBERT
Abstract: An acknowledge back (ack-back) paging system is provided 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.
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公开(公告)号：DE3854434T2
公开(公告)日：1996-04-18
申请号：DE3854434
申请日：1988-12-12
Applicant: MOTOROLA INC
Inventor： SIWIAK KAZIMIERZ , KEBA JAMES , STEEL FRANCIS ROBERT
Abstract: An acknowledge back (ack-back) pager is provided for use in a paging system including 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. To accurately control the ack-back transmit frequency, the pager receives and down-converts the FRX signal thus producing a down-converted FC signal, the frequency of which is measured and stored. The pager selects which sub-band of a plurality of frequency sub-bands within a predetermined range of frequencies is to be used for transmission of the ack-back signal. The pager determines a frequency offset FD corresponding to the selected sub-band, such offset being with respect to a predetermined frequency within such range of frequencies. The pager generates an acknowledge back signal at a frequency (FC+FD)-FCTX and up-converts such signal to a transmit frequency FTX corresponding to said selected sub-band, FCTX being the frequency of a down-converted sample of the FTX signal.
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公开(公告)号：AU3808178A
公开(公告)日：1980-01-17
申请号：AU3808178
申请日：1978-07-17
Applicant: MOTOROLA INC
Inventor： IRWIN JAMES STUART , STEEL FRANCIS ROBERT
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公开(公告)号：DE2646255A1
公开(公告)日：1977-05-05
申请号：DE2646255
申请日：1976-10-13
Applicant: MOTOROLA INC
Inventor： GILMORE MERLE LEE , STEEL FRANCIS ROBERT , TEMPKA JOHN ANTHONY
IPC: H04L27/00 , H04L27/227 , H04L27/233 , H04L27/22
Abstract: A digital detection system for binary differential phase shift keyed (DPSK) signals includes first and second multipliers to which the signal is applied, and which receive reference signals applied in quadrature to the two multipliers. The outputs of the multipliers are each applied through a filter to a one bit delay circuit, with the outputs of the filters and delay circuits being applied to third and fourth multipliers. The outputs of the third and fourth multipliers which receive signals from the two filters are summed to provide the detected digital signal. The filters may be matched filters each including an integrate, sample and dump circuit, and a data transition tracking loop coupled to the first multiplier and to the detector system output provides a bit synchronization signal for the matched filters. An I-Q loop may be coupled to the outputs of the two matched filters and controls an oscillator which provides the reference signals for the first and second multipliers. The addition of two multipliers and three summing circuits can extend the detection system for use with quaternary (four-phase) differential phase shift keyed signals.
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公开(公告)号：HK69197A
公开(公告)日：1997-05-30
申请号：HK69197
申请日：1997-05-22
Applicant: MOTOROLA INC
Inventor： JASINSKI LEON , STEEL FRANCIS ROBERT
Abstract: A system for transmitting long text messages includes a plurality of transmission cells defining different geographical areas, each having a transmitter for simulcast address transmission at a first data bit rate and for transmitting the address and a message at a second data bit rate higher than the first data bit rate. A paging transceiver generates and transmits an acknowledgment signal in response to receiving a transmitted address at the first data bit rate. Receivers located within each of the transmission cells receive the transmitted acknowledgment signal. An apparatus responsive to the received acknowledgment signal identifies the transmission cell in which the paging transceiver is located effecting the selection of the transmitter in the transmission cell in which the paging transceiver is located to transmit the address and message at the second data bit rate higher than the first data bit rate.
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