Method and apparatus for allowing communication units to utilize non-licensed title spectrum

• US 7,239,624 B2
• Filed: 10/26/2004
• Issued: 07/03/2007
• Est. Priority Date: 10/26/2004
• Status: Active Grant

• Current Assignee: Motorola Solutions, Inc.
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Kuffner, Stephen L., Ecklund, Lawrence M., Silk, S. David, Buchwald, Gregory J., Rachwalski, Richard S.
• Primary Examiner(s): LE, DANH C
• Application Number:
  US10/973,530
• Publication Number:
  US 20060088010A1
• Time in Patent Office: 980 Days
• Field of Search: 370/338, 370/433, 370/329, 455/450, 455/509, 348/725, 375/346
• US Class Current: 370/338
• CPC Class Codes: H04H 20/42 Arrangements for resource management
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks

Abstract

The presence of the non-television transmission within a channel is used to indicate that secondary non-licensed usage of the channel is permitted. Specifically, if secondary users incorporate the means to identify the unique modulation signature of the secondary user, decoding of a beacon signal may not be necessary. With the above in mind, a radio will be prevented from transmitting within a frequency band when no transmission within the licensed spectrum is currently taking place; the licensee is currently transmitting on the spectrum (e.g., television transmissions are taking place utilizing the spectrum, or the radio cannot sense the presence of a data channel (beacon).

Claims

1. A method for allowing a communication unit to utilized non-licensed spectrum, the method comprising the steps of:

determining if any transmissions are taking place within the non-licensed spectrum;

determining if any transmissions taking place within the non-licensed spectrum are by a licensed user of the spectrum;

determining if a beacon exists within the non-licensed spectrum; and

transmitting within the non-licensed spectrum only when transmissions are taking place within the non-licensed spectrum, the licensed user of the spectrum is not transmitting, and when a beacon exists.

2. The method of claim 1 wherein the step of determining if any transmissions taking place within the non-licensed spectrum are by the licensed user of the spectrum comprises the step of determining if a television broadcast is being made within the non-licensed spectrum.

3. The method of claim 2 wherein the step of determining if the television broadcast is being made comprises the step of searching for a visual carrier and an aural carrier to determine if the television broadcast is being made.

4. The method of claim 2 wherein the step of determining if the television broadcast is being made comprises the step of searching for a digital television (DTV), ATSC, or an NTSC signal and determining if a DTV, ATSC, or NTSC signal is present.

5. The method of claim 1 wherein the step of transmitting comprises the steps of:

determining guard bands for the non-licenses spectrum; and

transmitting within the guard bands of the non-licensed spectrum.

6. The method of claim 1 wherein the step of transmitting comprises the step of transmitting via a radio taken from the group consisting of a cellular telephone, a wireless computer, a wireless computer utilizing one of the IEEE 802 family of system protocols, medical telemetry equipment, and a wireless microphone.

7. The method of claim 1 wherein the step of determining if the beacon exists within the non-licensed spectrum comprises the step of analyzing a center of a single channel, an odd multiple of aggregate channels, or an edge of an aggregate even number of channels to determine if the beacon exists.

8. A method for allowing a communication unit to utilized television spectrum, the method comprising the steps of:

determining if any transmissions are taking place within the television spectrum;

determining if a television broadcast is taking place within the television spectrum;

determining if a beacon exists within the television spectrum; and

transmitting within the television spectrum only when transmissions are taking place within the television spectrum, the television broadcast is not taking place, and when a beacon exists.

9. The method of claim 8 wherein the step of determining if the television broadcast is taking place comprises the step of searching for a visual carrier and an aural carrier to determine if the television broadcast is taking place.

10. The method of claim 8 wherein the step of determining if the television broadcast is taking place comprises the step of searching for a digital television (DTV) signal and determining if a DTV signal is present.

11. The method of claim 8 wherein the step of transmitting comprises the steps of:

determining guard bands for the television spectrum; and

transmitting within the guard bands of the television spectrum.

12. The method of claim 8 wherein the step of transmitting comprises the step of transmitting via a radio taken from the group consisting of a cellular telephone, a wireless computer, a wireless equipment utilizing one of the IEEE 802 family of system protocols, medical telemetry equipment, and a wireless microphone.

13. An apparatus comprising:

logic circuitry determining if any transmissions are taking place within non-licensed spectrum, determining if any transmissions taking place within the non-licensed spectrum are by a licensed user of the spectrum, and determining if a beacon exists within the non-licensed spectrum; and

a transmitter transmitting within the non-licensed spectrum only when transmissions are taking place within the non-licensed spectrum, the licensed user of the spectrum is not transmitting, and when a beacon exists.

14. The apparatus of claim 13 wherein the logic circuitry determines if any transmissions taking place within the non-licensed spectrum are by the licensed user of the spectrum by determining if a television broadcast is being made within the non-licensed spectrum.

15. The apparatus of claim 13 wherein the logic circuitry determines if the television broadcast is being made by searching for a visual carrier and an aural carrier.

16. The apparatus of claim 13 wherein the logic circuitry determines if the television broadcast is being made by searching for a digital television (DTV).

17. The apparatus of claim 13 wherein the transmitter transmits within guard bands of the non-licenses spectrum.

18. The apparatus of claim 13 wherein the transmitter comprises a transmitter taken from the group consisting of a cellular telephone, a wireless computer, a wireless equipment utilizing one of the IEEE 802 family of system protocols, medical telemetry equipment, and a wireless microphone.