TDD frame format in wireless mesh network

• US 20090219839A1
• Filed: 02/29/2008
• Published: 09/03/2009
• Est. Priority Date: 02/29/2008
• Status: Active Grant

• Current Assignee: HMD Global Oy
• Original Assignee: Nokia Corporation
• Inventors: Zhao, Zhu Yan, Guan, Hao
• Granted Patent: US 7,808,934 B2
• Time in Patent Office: Days
• US Class Current: 370/280
• CPC Class Codes: H04W 74/02 Hybrid access
• CPC Class Codes: H04W 88/04 adapted for relaying to or from another terminal or user

Abstract

In a wireless mesh network a method includes, at a first node, receiving a transmission from a second node during a first sub-frame of a frame with a first transceiver operating with a first center frequency; processing the received transmission; and transmitting, after a predetermined fixed interval, with a second transceiver operating with a second center frequency the processed received transmission to a third node during a second sub-frame of a subsequent frame or of the same frame. Also disclosed are computer programs to execute the method, as well as apparatus constructed to implement the method.

Claims

1. A method, comprising:

at a first node, receiving a transmission from a second node during a first sub-frame of a frame with a first transceiver operating with a first center frequency;

processing the received transmission; and

transmitting, after a predetermined fixed interval, with a second transceiver operating with a second center frequency the processed received transmission to a third node during a second sub-frame of a subsequent frame or of the same frame.

2. The method of claim 1, where the subsequent frame is an immediately subsequent frame.

3. The method of claim 1, where the subsequent frame occurs after an intervening frame.

4. The method of claim 1, where the second node is a root node, where the first node is a first hop node relative to the root node, and where the third node is a second hop node relative to the root node.

5. The method of claim 1, where the second node is a second hop node relative to a root node, where the first node is a first hop node relative to the root node, and where the third node is the root node.

6. The method of claim 1, where when transmitting the processed received transmission to the third node during the second sub-frame of the same frame, the step of processing occurs during a guard time between the first sub-frame and the second sub-frame.

7. The method of claim 1, where the frame is a time division duplex frame comprised, for a given one of the first transceiver and the second transceiver, of a transmit sub-frame and a receive sub-frame, and where a duration of the transmit sub-frame is equal to the duration of the receive sub-frame.

8. The method of claim 1, where the frame is a time division duplex frame comprised, for a given one of the first transceiver and the second transceiver, of a transmit sub-frame and a receive sub-frame, and where a duration of the transmit sub-frame is not equal to the duration of the receive sub-frame.

9. The method of claim 8, where the duration of at least one of the transmit sub-frame and receive sub-frame is set in accordance with signaling.

10. The method of claim 8, where the duration of at least one of the transmit sub-frame and receive sub-frame is adjustable on a frame-by-frame basis.

11. The method of claim 1, where the step of receiving occurs through a first directional antenna, and where the step of transmitting occurs through a second directional antenna.

12. The method of claim 1, executed in a node that comprises part of a wireless mesh network having a tree topology.

13. A computer readable medium that stores computer program instructions, the execution of which at a first node results in operations that comprise:

receiving a transmission from a second node during a first sub-frame of a frame with a first transceiver operating with a first center frequency;

processing the received transmission; and

transmitting, after a predetermined fixed interval, with a second transceiver operating with a second center frequency the processed received transmission to a third node during a second sub-frame of a subsequent frame or of the same frame.

14. The computer readable medium of claim 13, where the subsequent frame is an immediately subsequent frame.

15. The computer readable medium of claim 13, where the subsequent frame occurs after an intervening frame.

16. The computer readable medium of claim 13, where the second node is a root node, where the first node is a first hop node relative to the root node, and where the third node is a second hop node relative to the root node.

17. The computer readable medium of claim 13, where the second node is a second hop node relative to a root node, where the first node is a first hop node relative to the root node, and where the third node is the root node.

18. The computer readable medium of claim 13, where when transmitting the processed received transmission to the third node during the second sub-frame of the same frame, the step of processing occurs during a guard time between the first sub-frame and the second sub-frame.

19. The computer readable medium of claim 13, where the frame is a time division duplex frame comprised, for a given one of the first transceiver and the second transceiver, of a transmit sub-frame and a receive sub-frame, and where a duration of the transmit sub-frame is equal to the duration of the receive sub-frame.

20. computer readable medium of claim 13, where the frame is a time division duplex frame comprised, for a given one of the first transceiver and the second transceiver, of a transmit sub-frame and a receive sub-frame, and where a duration of the transmit sub-frame is not equal to the duration of the receive sub-frame.

21. The computer readable medium of claim 20, where the duration of at least one of the transmit sub-frame and receive sub-frame is set in accordance with signaling, and may be adjustable on a frame-by-frame basis.

22. The computer readable medium of claim 13, where the step of receiving occurs through a first directional antenna, and where the step of transmitting occurs through a second directional antenna.

23. The computer readable medium of claim 13, embodied in a node that comprises part of a wireless mesh network having a tree topology.

24. An apparatus, comprising:

a first transceiver operating with a first center frequency;

a second transceiver operating with a second center frequency; and

a processor configurable to respond to receiving a transmission from a first node during a first sub-frame of a frame with the first transceiver for providing the received signal to the second transceiver for processing, further configurable for transmitting with the second transceiver, after a predetermined fixed interval, the processed received transmission to a second node during a second sub-frame of a subsequent frame or of the same frame.

25. The apparatus of claim 24, where the subsequent frame is one of an immediately subsequent frame or a frame that occurs after an intervening frame.

26. The apparatus of claim 24, where the first node is a root node, where the apparatus is embodied in a first hop node relative to the root node, and where the second node is a second hop node relative to the root node.

27. The apparatus of claim 24, where the first node is a second hop node relative to a root node, where the apparatus is embodied in a first hop node relative to the root node, and where the second node is the root node.

28. The apparatus of claim 24, where when transmitting the processed received transmission to the second node during the second sub-frame of the same frame the processing occurs during a guard time between the first sub-frame and the second sub-frame.

29. The apparatus of claim 24, where the frame is a time division duplex frame comprised, for a given one of the first transceiver and the second transceiver, of a transmit sub-frame and a receive sub-frame, and where a duration of the transmit sub-frame is one of equal to the duration of the receive sub-frame or not equal to the duration of the receive sub-frame.

30. The apparatus of claim 29, where the duration of at least one of the transmit sub-frame and receive sub-frame is set in accordance with signaling, and may be adjustable on a frame-by-frame basis.

31. The apparatus of claim 24, where the first transceiver operates with a first directional antenna, and where the second transceiver operates with a second directional antenna.

32. The apparatus of claim 24, embodied in a node that comprises part of a wireless mesh network having a tree topology.

33. An apparatus, comprising:

means for receiving a wireless transmission from a first node during a first sub-frame of a frame, said receiving means comprising a first directional antenna operating at a first frequency in a first time division duplex channel;

means for processing the received transmission; and

means for transmitting, after a predetermined interval, the processed received transmission to a second node during a second sub-frame of a subsequent frame or of the same frame, said transmitting means comprising a second directional antenna operating at a second frequency in a second time division duplex channel, where the subsequent frame is one of an immediately subsequent frame or a frame that occurs after an intervening frame.