System and apparatus for performing broadcast and localcast communications

• US 7,349,691 B2
• Filed: 10/26/2001
• Issued: 03/25/2008
• Est. Priority Date: 07/03/2001
• Status: Expired due to Fees

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Mitchell, William H., Karr, Lawrence J.
• Primary Examiner(s): Nguyen; Duc M.
• Application Number:
  US10/044,294
• Publication Number:
  US 20030008613A1
• Time in Patent Office: 2,342 Days
• Field of Search: 455/552, 455/553, 455/426.1, 455/426.2, 455/465, 455/422, 455/500, 455/507, 455/517, 455/11.1, 455/16, 455/17, 455/41.1, 455/41.2
• US Class Current: 455/422.1
• CPC Class Codes: G04G 21/04 using radio waves radio-controlled time-pieces G04R
• CPC Class Codes: H04B 1/385 Transceivers carried on the body, e.g. in helmets
• CPC Class Codes: H04H 20/18 Arrangements for synchronising broadcast or distribution via plural systems
• CPC Class Codes: H04H 20/30 by a single channel
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Described is a communication system including mobile communication devices. In the described system, the mobile devices many be wrist-worn watches such as are in common use today, except that the watches are specially configured to receive data in a “broadcast” mode and transmit and/or receive data in a “localcast” mode. The localcast mode includes the ability to transmit and receive data in a peer-to-peer fashion, allowing mobile devices to communicate directly with each other. The ability to combine two of these communication modes in a tiny, integrated and hence cheap and low-power package provides many advantages over existing personal communication device solution.

Claims

1. A system for performing wireless communications, comprising:

a broadcast transmission system configured to transmit broadcast information by employing wide-area FM subcarrier broadcasting on a predetermined schedule, wherein the broadcast information includes information for being conveyed to a user interface of a mobile device;

a localcast transmission system configured to transmit local information over a local area, wherein the local area is smaller than the wide area;

a peer-to-peer transmission system configured to transmit peer information; and

a mobile device comprising a transceiver that is configured to;

receive the broadcast information when the transceiver is in a broadcast mode and convey the broadcast information to the user interface of the mobile device;

receive the localcast information when the transceiver is in a localcast mode and convey the localcast information to the user interface of the mobile device;

transmit localcast information when the transceiver is in a localcast mode;

receive peer information when the transceiver is in a peer-to-peer mode and convey the peer information to the user interface of the mobile device;

transmit peer information when the transceiver is in a peer-to-peer mode;

transmit from a signal processing unit receive commands that describe a receive frequency, antenna tuning parameters, and a duration of capture time; and

adjust a variable tuning element to tune the antenna assembly in response to the receive commands.

2. The system of claim 1, wherein the broadcast transmitter further comprises:

an input-output controller that is coupled to a first input interface and to a buffer memory;

a control processor that is coupled to the input-output controller and to a second input interface;

a precision time base that is coupled to the control processor;

an encoding engine that is coupled to the input-output controller, the control processor, and to a first memory; and

a subcarrier signal generator that is coupled to the encoding engine, the control processor, a second memory, and to a subcarrier output.

3. The system of claim 2, wherein the input-output controller is arranged to receive data from an uplink device via the first input interface.

4. The system of claim 2, wherein the control processor is arranged to accept periodic commands and control information from an uplink device via the second input interface.

5. The system of claim 2, wherein the precision time base is arranged to track a master time-base associated with an uplink device, whereby transmission delays are minimized.

6. The system of claim 2, wherein the encoding engine is arranged to process frames of data received from an uplink device to produce an output image for transmission.

7. The system of claim 2, wherein the subcarrier signal generator is arranged to receive an output image from the encoding engine and generate a subcarrier signal for transmitting the broadcast information over the subcarrier channel.

8. An apparatus for transmitting a signal in a wireless communications system including a data source, comprising:

a broadcast transmitter configured to transmit broadcast information to a device over a subcarrier channel to a wide area according to a first transmission format, wherein the broadcast information includes information for being conveyed on a user interface of a mobile device;

a localcast transmitter coupled to the data source and configured to transmit local information to a device over a local area according to a second transmission format;

a mobile device comprising a transceiver that is configured to;

receive the broadcast information when the transceiver is in a broadcast mode and convey the broadcast information to a user interface of the mobile device;

receive the localcast information when the transceiver is in a localcast mode and convey the localcast information to a user interface of the mobile device;

transmit localcast information when the transceiver is in a localcast mode;

transmit from a signal processing unit receive commands that describe a receive frequency, antenna tuning parameters, and a duration of capture time; and

adjust a variable tuning element configured to tune the antenna in response to the receive commands.

9. An apparatus for transmitting a signal in a wireless communications system including a data source, comprising:

a mobile device comprising a transceiver that is configured to;

receive broadcast information from a broadcast transmitter when the transceiver is in a broadcast mode and convey the broadcast information to a user interface of the mobile device, wherein the broadcast information is received over a subcarrier channel distributed to a wide area according to a first format;

receive localcast information from a localcast transmitter when the transceiver is in a localcast mode and convey the localcast information to a user interface of the mobile device, wherein the localcast information is received over a locally-unused FM frequency over a local area according to a second format that is different from the first format;

transmit localcast information when the transceiver is in a localcast mode;

transmit from a signal processing unit receive commands that describe a receive frequency, antenna tuning parameters, and a duration of capture time; and

adjust a variable tuning element configured to tune the antenna in response to the receive commands.

10. An apparatus for performing wireless communications, comprising:

a mobile device comprising a transceiver that is configured to;

receive broadcast information from a broadcast transmitter when the transceiver is in a broadcast mode and convey the broadcast information to a user interface of the mobile device, wherein the broadcast information is received over a subcarrier channel distributed a wide area according to a first format;

receive localcast information from a localcast transmitter when the transceiver is in a localcast mode and convey the localcast information to a user interface of the mobile device, wherein the localcast information is received over a locally-unused FM frequency over a local area according to a second format;

receive peer information from a peer-to-peer transmitter when the transceiver is in a peer-to-peer mode and convey the peer information to a user interface of the mobile device, wherein the peer information is received from a peer device over a local area according to a third format;

transmit localcast information when the transceiver is in a localcast mode;

transmit peer information when the transceiver is in a peer-to-peer mode, wherein the peer information is transmitted in accordance with the third format;

transmit from a signal processing unit receive commands that describe a receive frequency, antenna tuning parameters, and a duration of capture time; and

adjust a variable tuning element configured to tune the antenna in response to the receive commands.

11. The apparatus of claim 10, wherein the localcast transmitter further comprises:

a first interface;

a control function that is coupled to the first interface;

an encoder that is coupled to the first interface and the control function;

processing logic that is coupled to the encoder and the control function;

a modulator that is coupled to the processing logic; and

an antenna.

12. The apparatus of claim 11, wherein the first interface is arranged to connect the localcast transmitter to its data source such that data packets are received by the localcast transmitter from the data source via the first interface.

13. The apparatus of claim 11, wherein the control function is arranged to collect data packets via the first interface, perform handshaking between the localcast transmitter and a data source, and set a desired transmission frequency, a mode, and a signal power.

14. The apparatus of claim 11, wherein the encoder is arranged to format data received from a data source as baseband samples, whereby encoding data for the localcast transmission is similar to encoding for broadcast transmission.

15. The apparatus of claim 11, wherein the processing logic is arranged to add correlation information for synchronization to audio samples received from the encoder.

16. The apparatus of claim 11, wherein the modulator is arranged to receive audio samples provided by the processing logic and produce an FM frequency output for transmitting data over a local area and in a locally-unused FM frequency.

17. The apparatus of claim 10, wherein the device configured to receive a wireless communication further comprises:

an antenna assembly;

a real-time component comprising;

a system timing function;

a real-time event dispatching function; and

a digital radio;

a digital control and processing circuit;

a microcomputer assembly;

a random access memory;

a nonvolatile memory; and

a microprocessor-controlled user interface.

18. The apparatus of claim 10, wherein the device is further arranged to transmit and receive information from a second mobile device.

19. The apparatus of claim 10, wherein the device is further arranged to receive information from a plurality of mobile devices and transmit data to a plurality of mobile devices.

20. The apparatus of claim 10, wherein the device is further arranged to receive wireless communications transmitted in a localcast mode from a second mobile device.

21. The apparatus of claim 10, wherein the device is further arranged to receive both the wireless communications transmitted in a localcast mode and the wireless communication transmitted in a broadcast mode using substantially the same circuitry.

22. An apparatus for performing wireless communications, comprising:

a mobile device including an antenna assembly;

a digital control and processing circuit;

a microcomputer assembly;

a random access memory;

a nonvolatile memory;

a microprocessor-controlled user interface; and

a real-time component having a system timing function, a real-time event dispatching function, and a digital radio; and

the mobile device being configured to;

receive broadcast information from a broadcast transmitter when the transceiver is in a broadcast mode and convey the broadcast information to a user interface of the mobile device, wherein the broadcast information is received over a subcarrier channel distributed to a wide area according to a first format;

receive localcast information from a localcast transmitter when the transceiver is in a localcast mode and convey the localcast information to a user interface of the mobile device, wherein the localcast information is received over a local area;

receive peer information from a peer-to-peer transmitter when the transceiver is in a peer-to-peer mode and convey the peer information to a user interface of the mobile device, wherein the peer information is received from a peer device over a local area;

transmit localcast information when the transceiver is in a localcast mode;

transmit peer information when the transceiver is in a peer-to-peer mode;

transmit from a signal processing unit receive commands that describe a receive frequency, antenna tuning parameters, and a duration of capture time; and

adjust a variable tuning element configured to tune the antenna in response to the receive commands.