Method and apparatus for dispatch communications in a broadcast radio system

• US 6,397,076 B1
• Filed: 11/05/1999
• Issued: 05/28/2002
• Est. Priority Date: 11/05/1999
• Status: Expired due to Fees

• Current Assignee: Sirius XM Radio Inc. (Liberty Media Corporation)
• Original Assignee: XM Satellite Radio Incorporated (Liberty Media Corporation)
• Inventors: Brown, David L., Wadin, Craig
• Primary Examiner(s): Trost, William
• Assistant Examiner(s): LE, DANH C
• Application Number:
  US09/434,734
• Time in Patent Office: 935 Days
• Field of Search: 455/45,185.1,186.1,404,521,426,522,518,519,305
• US Class Current: 455/521
• CPC Class Codes: H04H 20/26 Arrangements for switching distribution systems
• CPC Class Codes: H04H 2201/70 characterised in that receivers can be addressed
• CPC Class Codes: H04H 60/13 Arrangements for device control affected by the broadcast information

Abstract

A method and apparatus for receiving dispatch messages in a broadcast radio receiver. In one embodiment, audio dispatch messages can be received, in another embodiment, data dispatch messages can be received. In either embodiment, a previously selected broadcast channel is received until a dispatch alert message is simultaneously received. The dispatch alert message includes a dispatch ID codes which is compared by the receiver with a previously stored dispatch ID code. If equality is found, the receiver switches from the previously selected broadcast channel to a dispatch broadcast channel to receive the dispatch message. Upon completion of the dispatch message, the receiver automatically switches back to the previously selected broadcast channel.

Claims

1. A method of receiving with a receiver dispatch messages in a system which transmits dispatch alert messages on broadcast information channels, transmits dispatch messages on dispatch broadcast channels, and transmits program content on broadcast channels;

comprising the steps of;

simultaneously monitoring a broadcast information channel to receive dispatch messages and receiving program content on a broadcast channel;

receiving a dispatch alert message on said broadcast information channel which identifies a dispatch broadcast channel and a dispatch message ID code;

comparing said dispatch message ID code to one or more previously stored dispatch ID codes in the receiver, and upon finding equality therebetween;

receiving a dispatch message identified by said dispatch ID code on said dispatch broadcast channel, and

subsequently reverting to receiving said broadcast channel.

2. The method of claim 1 wherein said dispatch message comprises digital data and the receiver comprises a memory, further comprising the step of storing said dispatch message in the memory.

3. The method of claim 2 wherein the receiver includes a display and said method further comprises the step of displaying said dispatch message on the display.

4. The method of claim 1 wherein said dispatch message comprises audio data, the receiver comprises an output circuit coupled to an audio transducer and said method further comprises the steps of:

converting said dispatch message to an analog audio signal by the output circuit, and

reproducing said analog audio signal by the transducer.

5. The method of claim 4;

further comprising the step of storing the audio data in a memory for replay at a later time.

6. The method of claim 1 wherein said previously stored dispatch ID code is fixed within the receiver and is unique thereto.

7. The method of claim 1 wherein said previously stored dispatch ID code is fixed within the receiver and is shared by and common to all receivers operable within the system.

8. The method of claim 1 wherein the receiver comprises a memory and wherein said previously stored dispatch ID codes are programmable in the memory.

9. The method of claim 8 wherein the system broadcasts ID code assignment messages on the broadcast information channels, and the ID code assignment messages include assigned dispatch ID codes related to unique dispatch ID codes and said method further comprises the steps of:

receiving an ID code assignment message on said broadcast information channel, said ID code assignment message having an assigned dispatch ID code and a unique dispatch ID code therein;

comparing said unique dispatch ID code to said previously stored dispatch ID code and upon finding equality there between;

storing said assigned dispatch ID code in the memory, and

comparing subsequently received dispatch ID codes with both of said previously stored dispatch ID code and said assigned dispatch ID code stored in the memory for a determination of equality.

10. The method of claim 1 wherein the dispatch messages comprise termination data and said reverting to receiving said broadcast channel step occurs upon detecting termination data in said dispatch message.

11. The method of claim 1 wherein the dispatch message comprises periodic repetitions of the dispatch ID code and said reverting to receiving said broadcast channel occurs upon failure of detection of the dispatch ID code within the dispatch method.

12. The method of claim 10 wherein said reverting to receiving said broadcast channel step occurs in the event of not detecting said termination data within a predetermined time of receiving said dispatch message.

13. The method of claim 1 wherein said reverting to receiving said broadcast channel step occurs in the event of receiving a second dispatch message on said dispatch channel having a dispatch ID code that is not equal to said previously stored dispatch ID code.

14. A radio receiver system adapted to receive dispatch messages through an antenna in a system which transmits dispatch alert messages on broadcast information channels, transmits dispatch messages on dispatch broadcast channels, and transmits program content on broadcast channels;

said system comprising;

a receiver for outputting multiplexed data signals including broadcast information signals, broadcast signals, and dispatch broadcast signals;

a demultiplexer coupled to said output of said receiver for receiving said multiplexed data signals, said demultiplexer having a first output for outputting demultiplexed broadcast information signals and a second output for selectively outputting broadcast signals or dispatch signals in accordance with control commands;

an output circuit coupled to said second output of said demultiplexer for receiving said broadcast signals or said dispatch signals, said output circuit operable to convert said signals to analog audio signals;

an address correlator coupled to said first output of said demultiplexer for receiving said broadcast information signals therefrom and continuously compare the flow of data in said broadcast information signals to a previously stored dispatch ID code, said address correlator having a dispatch alert output which indicates the existence of equality between a received dispatch ID code in said broadcast information signals and said previously stored dispatch ID code, and

a controller coupled to said demultiplexer and said dispatch alert output, said controller responsive to said indication of equality to output control commands to said demultiplexer, causing it to change states from demultiplexing said broadcast information signals to demultiplexing said dispatch signals.

15. A radio receiver adapted to receive dispatch messages through an antenna in a system which transmits dispatch alert messages on broadcast information channels, transmits dispatch messages on dispatch broadcast channels, and transmits program content on broadcast channels;

comprising;

a receiver having an output which outputs multiplexed data signals including broadcast information signals, broadcast signals, and dispatch broadcast signals;

a demultiplexer coupled to said output of said receiver for receiving said multiplexed data signals, and having a first output for outputting demultiplexed broadcast information signals and a second output for selectively outputting broadcast signals or dispatch signals in accordance with control commands;

an memory coupled to said second output of said demultiplexer for receiving said broadcast signals or said dispatch signals;

an address correlator coupled to said first output of said demultiplexer for receiving said broadcast information signals therefrom and continuously compare the flow of data in said broadcast information signals to a previously stored dispatch ID code, said address correlator having a dispatch alert output which indicates the existence of equality between a received dispatch ID code in said broadcast information signals and said previously stored dispatch ID code, and

a controller coupled to said demultiplexer and said dispatch alert output, said controller responsive to said indication of equality to output control commands to said demultiplexer, causing it to change states from demultiplexing said broadcast information signals to demultiplexing said dispatch signals.