Active signalling transmitter control

• US 4,972,439 A
• Filed: 01/19/1989
• Issued: 11/20/1990
• Est. Priority Date: 01/19/1989
• Status: Expired due to Term

• Current Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Schwendeman, Robert J., Kuznicki, William J.
• Primary Examiner(s): Olms, Douglas W.
• Assistant Examiner(s): Huseman, Marianne
• Application Number:
  US07/299,187
• Time in Patent Office: 670 Days
• Field of Search: 375/121, 375/3, 375/4, 375/60, 375/62, 375/59, 340/825.44, 340/825.47, 340/825.48, 340/825.72, 340/825.76, 455/53, 455/33, 455/52, 455/54, 455/69, 455/68, 455/43, 455/44, 455/92, 370/110.1, 379/63
• US Class Current: 375/296
• CPC Class Codes: H04J 3/0605 Special codes used as synchronising signal
• CPC Class Codes: H04L 25/242 with retiming
• CPC Class Codes: H04W 52/42 in systems with time, space, frequency or polarisation diversity
• CPC Class Codes: H04W 88/187 using digital or pulse address codes

Abstract

A transmitter, having controllable transmission functions is described for transmitting coded message signals to a plurality of portable communications receivers, the coded message signals including and message information interleaved with transmitter control signals synchornized with the message information. The transmitter includes a receiving section for receiving the coded message signals from an input source for transmission. A decoder which couples to the receiving section decodes the synchronized transmitter control signals to derive transmission control signals. A transmitter section, responsive to the transmission control signals, transmits the coded message signals. Additional transmission control signals may also be derived from one or more receiver control signals embedded in the coded message signals.

Claims

1. A transmitter, having controllable transmission functions, for transmitting coded message signals to a plurality of portable communication receivers, the coded message signals including message information interleaved with transmitter control signals and receiver control signals, the transmitter comprising:

receiving means, coupled to a communication link, for receiving the coded message signals transmitted thereon;

decoding means, coupled to said receiving means, for decoding the transmitter control signals and one or more of the receiver control signals, deriving transmission control signals in response thereto; and

transmitting means, responsive to the transmission control signals for transmitting the coded message signals.

2. The transmitter according to claim 1, wherein said transmitter means includes signal processing means and responsive to the transmission control signals, for processing the coded message signals for transmission.

3. The transmitter according to claim 2, wherein said decoding means generates at least first and second transmission control signals for controlling the transmission of coded message signals at at least first and second baud rates, and wherein said signal processing means comprises:

modulation means, coupled to said receiving means, for modulating the coded message signals; and

low pass filter means coupled to said modulation means, and having at least first and second selectable cut-off frequencies, said filter means responsive to the first transmission control signal for selecting the first cut-off frequency and further responsive to the second transmission control signal for selecting the second cut-off frequency.

4. The transmitter according to claim 3 wherein said modulation means comprises a frequency modulation (FM) modulator.

5. The transmitter according to claim 4, wherein said modulation means further comprises deviation level control means for generating at least first and second deviation signal levels.

6. The transmitter according to claim 5, wherein said deviation level control means being responsive to said first transmission control signal for selecting the first deviation signal level and further responsive to the second transmission control signal for selecting the second deviation signal level.

7. The transmitter according to claim 3 wherein said decoding means generating first and second transmission control signals for controlling carrier modulation, and wherein said modulation means being further responsive to the first transmission control signal for generating modulated carrier, and being further responsive to the second transmission control signal for generating an unmodulated carrier.

8. The transmitter according to claim 2 wherein said decoding means generating first and second transmission control signals for controlling the transmission of coded message signals, and wherein said transmitter means being further coupled to said decoding means and responsive to the first transmission control signal for keying said transmitter means, and being further responsive in the second transmission control signal for de-keying said transmitter means.

9. The transmitter according to claim 2 wherein the coded message signals transmitted by said transmitter means includes the message information interleaved with the communication receiver control signals.

10. The transmitter according to claim 3 wherein said signal processing means further comprising delay means, coupled to said receiving means and to said modulation means, for delaying the time of transmission of the coded message signals for a predetermined delay time interval.

11. The transmitter according to claim 10 wherein said delay means being programmable for providing a plurality of predetermined delay time intervals.

12. The transmitter according to claim 11 wherein said decoding means further generating first and second transmission control signals during transmission of coded message signals at first and second baud rates, and wherein said programmable delay means being responsive to the first transmission control signal for selecting a first predetermined delay time interval from the plurality of predetermined delay time intervals, and further responsive to the second transmission control signals for selecting a second predetermined delay time interval from the plurality of predetermined delay time intervals, thereby controlling the time of transmission of the coded message signals.

13. The transmitter according to claim 12 wherein said delay means further comprising programmable memory means for storing the first and second predetermined delay time intervals.

14. The transmitter according to claim 13 wherein either said first or said second predetermined delay time intervals may be zero.

15. The transmitter according to claim 1 wherein said transmitter means further comprising transmitter power control means for transmitting the coded message signals with at least first and second output power levels.

16. The transmitter according to claim 15, wherein said decoding means further generates a third transmission control signal for controlling the transmission of coded message signals at a first and second baud rates, and wherein said transmitter power control means being responsive to said first transmission control signal for selecting the transmission of the coded message signals at the first output power level, and being further responsive to the second transmission control signal for selecting the transmission of the coded message signals at the second output power level.

17. The transmitter according to claim 1 wherein said decoding means comprises a microprocessor.

18. The transmitter according to claim 1 wherein the coded message signals further include address signals to which the portable communications receivers are responsive for receiving the message signals and receiver control signals.

19. The transmitter according to claim 1 wherein said coded message signals are digital codewords.

20. The transmitter according to claim 1 wherein said decoding means comprises:

timing means for generating timing signals; and

synchronization means, responsive to the synchronized transmitter control signals, for synchronizing the timing signals with the coded message signals received for transmission.