Method and apparatus for reliably communicating information packets in a wireless communication network

• US 6,741,554 B2
• Filed: 08/16/2002
• Issued: 05/25/2004
• Est. Priority Date: 08/16/2002
• Status: Active Grant

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Gorday, Paul E., Simpson, Floyd D., DʼAmico, Thomas Victor
• Primary Examiner(s): Kizou, Hassan
• Assistant Examiner(s): Levitan, Dmitry
• Application Number:
  US10/222,317
• Publication Number:
  US 20040032853A1
• Time in Patent Office: 648 Days
• Field of Search: 370/216, 370/225, 370/227, 370/228, 370/276, 370/277, 370/278, 370/279, 370/280, 370/281, 370/294, 370/295, 370/310, 370/313, 370/314, 370/343, 370/344, 370/345, 370/349, 709/230, 709/236, 709/238, 709/239, 709/240, 714/748, 714/749
• US Class Current: 370/225
• CPC Class Codes: H04L 1/02 by diversity reception
• CPC Class Codes: H04L 1/1893 Physical mapping arrangements physical resource mapping in general H04L5/00
• CPC Class Codes: H04L 1/22 using redundant apparatus to increase reliability

Abstract

A wireless communication network (100) employs a method and apparatus for reliably communicating information packets in the network. A first wireless device (101) in the network transmits an information packet to a second wireless device (e.g., 102) in the network over a first wireless communication channel (403, 404). The first device then determines whether the information packet was successfully received (e.g., received without errors) by the second device. If the information packet was not successfully received, the first device retransmits the information packet to the second device over a second wireless communication channel (405, 406). In addition, and preferably substantially contemporaneous with retransmission of the first information packet, the first device transmits a second information packet to the second device over the first channel in an effort to communicate an information sequence to the second device without delays typically associated with use of a reliable protocol.

Claims

1. A method for a first wireless device to reliably communicate information packets to a second wireless device in a wireless communication network, the method comprising the steps of:

transmitting a first information packet to the second wireless device over a first wireless communication channel;

determining whether the first information packet was successfully received by the second wireless device;

retransmitting the first information packet to the second wireless device over a second wireless communication channel in the event that the first information packet was not successfully received by the second wireless device; and

transmitting at least a second information packet to the second wireless device over the first wireless communication channel substantially contemporaneously with retransmitting the first information packet, wherein the first information packet and the at least a second information packet form a sequence of information.

2. The method of claim 1, further comprising the steps of:

prior to the step of transmitting the first information packet,

determining respective signal quality levels for a plurality of wireless communication channels that are available for use in the wireless communication network;

receiving signal quality information for the plurality of wireless communication channels from the second wireless device; and

selecting the second wireless communication channel from the plurality of wireless communication channels based on the signal quality levels and the received signal quality information.

3. The method of claim 1, further comprising the steps of:

storing the first information packet in a memory of the first wireless device;

retrieving the first information packet from the memory in the event that the first information packet is to be retransmitted; and

deleting the first information packet from the memory in the event that the first information packet was determined to be successfully received by the second wireless device.

4. The method of claim 1, wherein the first wireless communication channel and the second wireless communication channel are two of a plurality of wireless communication channels available for use in the wireless communication network, the method further comprising the steps of:

determining a signal quality level of the second wireless communication channel;

receiving signal quality information relating to the second wireless communication channel from the second wireless device; and

selecting a third wireless communication channel from the plurality of wireless communication channels for purposes of retransmitting unsuccessfully received information packets in the event that at least one of the signal quality level and the signal quality information indicates unacceptable signal quality of the second wireless communication channel.

5. The method of claim 4, wherein the steps of determining a signal quality level and receiving signal quality information are performed on a regular basis in order to permit a substantially continuous signal quality determination of the second wireless communication channel at least while the second wireless communication channel is being utilized for purposes of retransmitting unsuccessfully received information packets.

6. The method of claim 1, wherein the first wireless communication channel and the second wireless communication channel are two of a plurality of wireless communication channels available for use in the wireless communication network, the method further comprising the steps of:

determining signal quality levels of the second wireless communication channel and of a third wireless communication channel;

receiving signal quality information relating to the second wireless communication channel and the third wireless communication channel from the second wireless device;

determining expected signal quality of the second wireless communication channel and of the third wireless communication channel based upon the signal quality levels and the signal quality information; and

selecting the third wireless communication channel from the plurality of wireless communication channels for purposes of retransmitting unsuccessfully received information packets in the event that the expected signal quality of the third wireless communication channel Is more favorable than the expected signal quality of the second wireless communication channel.

7. The method of claim 1, wherein the wireless communication network employs a time division multiple access protocol in which information is communicated in time slots arranged into time frames, wherein the first wireless communication channel is at least one time slot on a first carrier frequency and wherein the second wireless communication channel is at least one time slot on a second carrier frequency.

8. The method of claim 7, wherein the step of transmitting the second information packet comprises the step of:

transmitting the second information packet in at least one time slot over the first carrier frequency during a time frame in which the first information packet is retransmitted in at least one time slot over the second carrier frequency.

9. The method of claim 1, wherein the wireless communication network employs a time division multiple access protocol in which information is communicated in time slots arranged into time frames, wherein the first wireless communication channel is at least one time slot on a first carrier frequency and wherein the second wireless communication channel is at least one other time slot on the first carrier frequency.

10. The method of claim 1, wherein the information packets include real-time information.

11. The method of claim 10, wherein the second wireless communication channel is used primarily in support of non-real-time information packet transmissions and secondarily for purposes of retransmitting unsuccessfully received, real-time information packets.

12. A method for a first wireless device to reliably communicate information packets to a second wireless device in a wireless local area network, the method comprising the steps of:

transmitting a first information packet to the second wireless device over a first wireless communication channel, the first information packet including real-time information;

transmitting packetized, non-real-time information to at least one of the second wireless device and a third wireless device over a second wireless communication channel;

determining whether the first information packet was successfully received by the second wireless device;

in the event that the first information packet was not successfully received by the second wireless device,

temporarily interrupting transmission of the packetized, non-real-time information over the second wireless communication channel;

retransmitting the first information packet to the second wireless device over the second wireless communication channel; and

substantially contemporaneous with retransmission of the first information packet, transmitting a second information packet to the second wireless device over the first wireless communication channel, wherein the first information packet and the second information packet form a sequence of information.

13. The method of claim 12, wherein the first wireless communication channel and the second wireless communication channel are two of a plurality of wireless communication channels available for use in the wireless local area network, the method further comprising the steps of:

temporarily and regularly interrupting transmissions of the packetized, non-real-time information over the second wireless communication channel to produce interrupt periods;

determining signal quality levels of the second wireless communication channel during the interrupt periods;

receiving signal quality information relating to the second wireless communication channel from the second wireless device; and

selecting a third wireless communication channel from the plurality of wireless communication channels for purposes of retransmitting unsuccessfully received information packets in the event that at least one of the signal quality levels and the signal quality information indicate unacceptable signal quality of the second wireless communication channel.

14. The method of claim 12, wherein the wireless local area network employs a time division multiple access protocol in which information is communicated in time slots arranged into time frames, wherein the first wireless communication channel is at least one time slot on a first carrier frequency, wherein the second wireless communication channel is at least one time slot on a second carrier frequency, and wherein the step of transmitting the second information packet substantially contemporaneous with retransmission of the first information packet comprises the step of:

transmitting the second information packet in at least one time slot over the first carrier frequency during a time frame in which the first information packet is retransmitted in at least one time slot over the second carrier frequency.

15. A method for a first wireless device to reliably receive information packets from a second wireless device in a wireless communication network, the method comprising the steps of:

receiving a first information packet from the second wireless device over a first wireless communication channel;

informing the second wireless device as to whether the first information packet was successfully received;

receiving the first information packet from the second wireless device over a second wireless communication channel in the event that the first information packet was not successfully received previously; and

receiving at least a second information packet from the second wireless device over the first wireless communication channel substantially contemporaneously with receiving the first information packet over the second wireless communication channel, wherein the first information packet and the at least a second information packet form a sequence of information.

16. The method of claim 15, further comprising the steps of:

in the event that the first information packet was not originally received successfully on the first wireless communication channel, storing the first information packet in memory until receipt of the first information packet over the second wireless communication channel to produce a stored information packet;

combining the stored information packet with the first information packet received on the second wireless communication channel to produce a corrected information packet; and

processing the corrected information packet and the at least a second information packet to reconstruct the sequence of information.

17. The method of claim 15, further comprising the steps of:

in the event that the first information packet was not originally received successfully on the first wireless communication channel, storing the first information packet in memory until receipt of the first information packet over the second wireless communication channel to produce a stored information packet;

replacing the stored information packet with the first information packet received over the second wireless communication channel to produce a corrected information packet; and

processing the corrected information packet and the at least a second information packet to reconstruct the sequence of information.

18. The method of claim 15, further comprising the steps of:

prior to the step of receiving the first information packet over the first wireless communication channel,

determining respective signal quality levels for a plurality of wireless communication channels that are available for use in the wireless communication network;

transmitting the signal quality levels to the second wireless device; and

receiving an identification of the second wireless communication channel from the second wireless device, the second wireless communication channel being selected from the plurality of wireless communication channels based at least on the signal quality levels.

19. The method of claim 15, wherein the first wireless communication channel and the second wireless communication channel are two of a plurality of wireless communication channels available for use in the wireless communication network, the method further comprising the steps of:

determining a signal quality level of the second wireless communication channel;

transmitting the signal quality level to the second wireless device; and

receiving an identification of a third wireless communication channel from the second wireless device in the event that at least one of (a) the signal quality level and (b) signal quality information determined by the second wireless device indicates unacceptable signal quality of the second wireless communication channel, the third wireless communication channel being selected from the plurality of wireless communication channels for use in retransmitting unsuccessfully received information packets.

20. The method of claim 15, wherein the first wireless communication channel is a time division duplex channel and wherein the step of informing the second wireless device comprises the step of:

transmitting an acknowledgment message to the second wireless device in a first time slot of a first time frame, the first time slot occurring later in time than a second time slot of the first time frame in which the first information packet was received, but earlier in time than commencement of a second time frame.

21. The method of claim 15, wherein the wireless communication network employs a time division multiple access protocol in which information is communicated in time slots arranged into time frames, wherein the first wireless communication channel is at least one time slot on a first carrier frequency and the second wireless communication channel is at least one time slot on a second carrier frequency, and wherein the step of receiving at least a second information packet on the first wireless communication channel comprises the step of:

receiving a second information packet in at least one time slot over the first carrier frequency during a time frame in which the first information packet is received in at least one time slot over the second carrier frequency.

22. The method of claim 15, wherein the information packets include real-time information and wherein the second wireless communication channel is used primarily in support of non-real-time information packet transmissions and secondarily for purposes of retransmitting unsuccessfully received, real-time information pockets.

23. A wireless base transceiver station system comprising:

a program memory that stores operating instructions for performing particular functions;

a controller that executes the operating instructions stored in the program memory to perform at least the following functions;

allocate wireless communication channels in support of communicating information packets to wireless electronic devices,

control transmission of the information packets to the wireless electronic devices, and

determine, based on at least one of information received and lack of information received from a first wireless electronic device, whether a first information packet transmitted to the first wireless electronic device was successfully received by the first wireless electronic device;

a transmitter, responsive to the controller, that transmits the first information packet to the first wireless electronic device over a first wireless communication channel, retransmits the first information packet to the first wireless electronic device over a second wireless communication channel in the event that the first information packet was not successfully received by the first wireless electronic device, and transmits at least a second information packet to the first wireless electronic device over the first wireless communication channel substantially contemporaneously with retransmitting the first information packet, wherein the first information packet and the at least a second information packet form a sequence of information; and

a receiver, operably coupled to the controller, that receives information from the wireless electronic devices.

24. The wireless base transceiver station system of claim 23, further comprising:

a buffer memory, operably coupled to the controller, that stores the first information packet at least until the controller determines that the first information packet was successfully received by the first wireless electronic device.

25. A wireless device comprising:

a receiver that receives an initial transmission of a first information packet from a second wireless device over a first wireless communication channel, receives a retransmission of the first information packet over a second wireless communication channel in the event that the initial transmission of the first information packet was not acceptable, and receives at least a second information packet from the second wireless device over the first wireless communication channel substantially contemporaneously with receiving a retransmission of the first information packet, the first information packet and the at least a second information packet forming a sequence of information;

a program memory that stores operating instructions for performing particular functions;

a processor, operably coupled to the receiver and the program memory, that executes the operating instructions stored in the program memory to perform at least the following functions;

determine whether the initial transmission of the first information packet received from the second wireless device is acceptable;

inform the second wireless device as to whether the initial transmission of the first information packet is acceptable; and

process the first information packet and the at least a second information packet to reconstruct the sequence of information upon successful reception of the first information packet and the at least a second information packet; and

a transmitter, responsive to the processors that transmits information to the second wireless device.

26. The wireless device of claim 25, further comprising:

a buffer memory, operably coupled to the processor, tat stores the first information packet to produce a stored information packet until receipt of the first information packet over the second wireless communication channel in the event that the initial transmission of the first information packet was not acceptable; and

wherein the operating instructions include instructions that, when executed by the processor, enable the processor to further perform the following functions;

combine the stored information packet with the first information packer received over the second wireless communication channel to produce a corrected information packet; and

process the corrected information packet and the at least a second information packet to reconstruct the sequence of information.

27. The wireless device of claim 26, wherein the buffer memory further stores the at least a second information packet until receipt of the first information packet over the second wireless communication channel in the event that the initial transmission of the first information packet was not acceptable.

28. The wireless device of claim 25, further comprising:

a buffer memory, operably coupled to the processor, that stores the first information packet to produce a stored information packet until receipt of the first information packet over the second wireless communication channel in the event that the initial transmission of the first information packet was not acceptable; and

wherein the operating instructions include instructions that, when executed by the processor, enable the processor to further perform the following functions;

replace the stored information packet with the first information packet received over the second wireless communication channel to produce a corrected information packet; and

process the corrected information packet and the at least a second information packet to reconstruct the sequence of information.

29. The wireless device of claim 25, wherein the information transmitted by the transmitter includes an acknowledgment message indicating that the initial transmission of the first information packet was not acceptable.