WIRELESS TRANSMITTER INITIATED COMMUNICATION METHODS

• US 20070091825A1
• Filed: 10/21/2005
• Published: 04/26/2007
• Est. Priority Date: 10/21/2005
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Gonia, Patrick, Kolavennu, Soumitri, Budampati, Ramakrishna
• Granted Patent: US 8,644,192 B2
• Time in Patent Office: Days
• US Class Current: 370/255
• CPC Class Codes: H04B 1/713 using frequency hopping
• CPC Class Codes: H04W 72/02 Selection of wireless resources by user or terminal
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

Wireless communication systems using transmitter initiated communications methods. Several devices in the system listen by following a common frequency hopping sequence. When communication is desired, a transmitting device sends a request to send signal to an addressee; if available, the addressee sends a clear to send signal, and the transmitting device and the addressee then perform communications using a separate frequency hopping sequence. Methods for adding new devices are also included. In an example, a new device uses a discovery frequency hopping sequence to ping a number of frequencies until the common frequency hopping sequence is discovered. In another example, a new device listens on a single frequency forming part of the common frequency hopping sequence until the common frequency hopping sequence overlaps the single frequency.

Claims

1. A method of wireless communication comprising:

providing a system of peer communication devices configured for sending and receiving signals wirelessly;

the peer communication devices following a first channel succession defining a number of communications channels to which the communication devices are tuned at particular times;

a first peer communication device generating a request to send data to a second peer communication device using a first channel in the channel succession;

the second peer communication device receiving the request to send data from the first peer communication device and generating a clear to send data message to the first peer communication device using the first channel;

the first and second peer communication devices then following a second channel succession to perform data transfer between the first peer communication device and the second peer communication device; and

when a new device is added to the system, the new device entering into a discovery mode wherein the new device learns the system timing and the state of the first channel succession.

2. The method of claim 1 wherein the step of the new device entering into a discovery mode includes the new device observing a selected channel from among the number of communications channels for a period of time predetermined to assure that the peer communication devices will use the observed channel during the period of time.

3. The method of claim 1 wherein the step of the new device entering into a discovery mode includes the new device following a third channel succession, the third channel succession changing channels more quickly than the first or second channel successions.

4. The method of claim 1 wherein the step of the new device entering into a discovery mode includes the new device transmitting hailing messages on succession of channels until a response is received or a time out is observed.

5. The method of claim 1 wherein the first and second channel successions are pseud-orandom frequency hopping spread spectrum successions.

6. The method of claim 1 wherein the first and second channel successions are CDMA successions.

7. The method of claim 1 wherein the second channel succession is defined by the second peer communication device.

8. The method of claim 7 wherein the step of the second peer communication device generating a clear to send message includes the second peer communication device sending data indicative of the second channel succession to the first peer communication device.

9. The method of claim 1 wherein the system further comprises a central time device, and the method further includes the central time device periodically generating a time synchronization signal.

10. The method of claim 9 wherein the first and second peer communication devices are each located a number of hops from the central time device, wherein one of the first or second peer communication device is a closer device with respect to the central time device, wherein, during communication between the first and second peer communication devices, a time synchronization signal is generated by the closer device and communicated to the other device.

11. The method of claim 1 wherein the second channel succession is defined by the first peer communication device.

12. The method of claim 11 wherein the step of the first peer communication device generating a request to send data message includes the first peer communication device sending data indicative of the second channel succession to the second peer communication device.

13. The method of claim 1 further comprising at least one of the plurality of peer communication devices sending a broadcast message to the other peer communication devices using a channel defined in the first channel succession.

14. The method of claim 1 further comprising the first peer communication device performing a clear channel assessment on the first channel before sending the request to send message.

15. The method of claim 1 further comprising:

a third peer communication device generating a request to send data message to a fourth peer communication device using the first channel after the first and second peer communication devices generate their respective request to send data and clear to send data messages on the first channel;

the fourth peer communication device generating a clear to send data message in response to the request to send data message from the third peer communication device; and

the third peer communication device sending to the fourth peer communication device using a channel defined in a third channel succession.

16. The method of claim 15 further comprising one of the third or the fourth peer communication device defining the third channel succession.

17. The method of claim 15 further comprising the third peer communication device performing a clear channel assessment on the first channel before transmitting the request to send message.

18. A method of wireless communication for a communication system comprising a number of peer devices configured to generate requests to send data when data is ready to send, the method comprising:

the devices in the system following a first channel succession when not transmitting data;

when a first device is prepared to send data, the device addressing a request to send data to a second device;

the second device sending a clear to send data message to the first device; and

the first and second devices following a second channel succession when transmitting data, the second channel succession being different from the first channel succession.

19. A method of wireless communication for a communication system comprising a number of peer devices configured to generate requests to send data when data is ready to send, wherein new devices can be added to the system, the method comprising:

when a new device is added to the system, the new device defaulting to a discovery process, the discovery process comprising listening on a single channel chosen from a number of channels included in the first channel succession until either the new device times out, or until a message is generated by one of the existing peer devices in the single channel; and

once the message is generated on the single channel, the new device time synchronizing with the other peer devices.

20. A method of wireless communication for a communication system comprising a number of peer devices configured to generate requests to send data when data is ready to send, wherein new devices can be added to the system, the method comprising:

when a new device is added to the system, the new device defaulting to a discovery process, the discovery process comprising following a second channel succession covering channels covered by the first channel succession until either the new device times out, or until a message is generated by one of the existing peer devices and captured by the new device.

21. The method of claim 20 wherein the discovery process includes the new device generating a hailing signal at channels determined by the second channel succession.

22. The method of claim 20 wherein the first channel succession is configured to include a repeating frame including a discovery subframe for discovering new devices and an operation subframe for peer devices to communicate with one another.

23. The method of claim 22 wherein the discovery process includes the new device generating a hailing signal at channels determined by the second channel succession, the new device operating with a periodicity enabling the new device to hail at least two channels during each discovery subframe.