Methods for controlling shared access to wireless transmission systems and increasing throughput of the same

• US 6,795,407 B2
• Filed: 04/20/2001
• Issued: 09/21/2004
• Est. Priority Date: 04/22/2000
• Status: Expired due to Term

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Atheros Communications Incorporated (Qualcomm, Inc.)
• Inventors: Chesson, Gregory Lawrence
• Primary Examiner(s): Vu, Huy D.
• Assistant Examiner(s): RYMAN, DANIEL J
• Application Number:
  US09/839,647
• Publication Number:
  US 20020045428A1
• Time in Patent Office: 1,250 Days
• Field of Search: 370/310, 370/328, 370/329, 370/330, 370/331, 370/332, 370/333, 370/334, 370/335, 370/336, 370/337, 370/338, 370/447, 370/311, 370/341, 370/465
• US Class Current: 370/311
• CPC Class Codes: H04L 1/18 Automatic repetition systems, e.g. Van Duuren systems
• CPC Class Codes: H04W 52/34 TPC management, i.e. sharing limited amount of power among users or channels or data types, e.g. cell loading
• CPC Class Codes: H04W 52/346 distributing total power among users or channels
• CPC Class Codes: H04W 52/50 at the moment of starting communication in a multiple access environment
• CPC Class Codes: H04W 74/006 in the downlink, i.e. towards the terminal
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

A wireless communication system implements a calibration mode by which individual nodes in the system can determine which other nodes in the system are physically close to them and therefore can be reached with less than full transmitting power. Nodes which can communicate with one another via low power can form a low power constellation (a subset of the complete network) whose nodes can communicate directly with one another using this low power arrangement. The direct communication mode may additionally be used by itself. In another mode, the nodes in the system can communicate amongst themselves via bridges—other, non-access point nodes—to lessen the load on the access point or to accommodate environmental or other conditions. Various ones of these modes may be combined into a predetermined cycle of communication modes to help the physical layer accommodate various types of data handled by the network using beacons or another coordinating technique. Overhead in the form of packet retransmission may be reduced by interpolating to recover lost packets rather than retransmitting them.

Claims

1. A method of establishing overlaid communications in a multi-carrier communication system between a plurality of wireless stations each capable of communicating on less than all carriers in the multi-carrier communication system comprising the steps of:

providing each of the plurality of wireless stations capable of performing overlaid communications in the multi-carrier communication system a message which includes an assigned carrier and a commonly assigned calibration transmit power level for transmission,

allowing a period of time for each of the plurality of wireless stations to transmit at least one calibration message on the assigned carrier at the commonly assigned calibration power level;

transmitting from each of the plurality of wireless stations at least one calibration message on the assigned carrier at the commonly assigned calibration power level;

receiving from each of the plurality of wireless stations information indicating transmissions from other ones of the plurality of wireless stations that they received and the receive power level of each of these received transmissions; and

using the received information to map which ones of the plurality of wireless stations can communicate with other ones of the plurality of wireless stations on assigned carriers, at a common transmit power level chosen from a plurality of available transmit power levels so that subsequent signals from some of the plurality of wireless stations arriving at substantially the same time at another of the wireless stations have a substantially similar receive power level at the another wireless station.

2. The method according to claim 1 wherein the step of transmitting transmits from each of the plurality of wireless stations a plurality of calibration messages.

3. The method according to claim 2 wherein each of the plurality of calibration messages for each of the plurality of wireless stations is transmitted at different power levels.

4. The method according to claim 3 wherein each of the plurality of power calibration messages for each of the plurality of wireless stations is transmitted at increasing power levels.

5. The method according to claim 3 wherein each of the plurality of power calibration messages for each of the plurality of wireless stations is transmitted at decreasing power levels.

6. The method according to claim 1 wherein the steps of providing and receiving occur at the another wireless station.

7. The method according to claim 6 wherein the another wireless station is an access point.

8. The method according to claim 1 wherein it is determined that a first wireless station cannot communicate with a second wireless station at one of the available power levels at the same time without preventing a third wireless station from communicating.

9. The method according to claim 8 wherein it is determined that the first wireless station cannot communicate with the second wireless station at one of the available power levels at the same time without saturating the third wireless station.

10. The method according to claim 1 wherein the message further specifies the period of time.

11. The method according to claim 1 wherein the message further specifies one of a plurality of calibration periods that exist during the period of time for each of the plurality of wireless stations to transmit at on the assigned carrier and at the assigned power level.

12. The method according to claim 11 wherein each of the plurality of wireless stations transmit during the period of time the calibration message containing therein an identifier of the transmitting wireless station and a transmit power level at which the calibration message is being transmitted.

13. The method according to claim 12 wherein the received calibration message from various ones of the transmitting wireless stations is collected at each receiving wireless station and used to obtain the information during the step of receiving.

14. The method according to claim 1 wherein the step of providing the message provides the carrier assignment using a vector having a number of elements equal to a number of available carriers.

15. The method according to claim 1 further including a transmission period during which the plurality of wireless stations communicate within constraints of the map.

16. The method according to claim 15 wherein during the transmission period, at least one pair of the plurality of wireless stations communicate such that an acknowledgement after a transmission is not used.

17. The method according to claim 1 wherein during the period of time, transmissions of different calibration messages on respectively different overlaid carriers can take place at the same time.

18. The method according to claim 1, wherein:

the multi-carrier communication system operates on a single frequency channel; and

the multi-carrier communication system subdivides the single frequency channel to form all available carriers.

19. A method of establishing communications in a multi-carrier communication system between a plurality of wireless stations each capable of communicating on less than all carriers in the multi-carrier communication system comprising the steps of:

providing each of the plurality of wireless stations capable of performing communications in the multi-carrier communication system a message which includes a commonly assigned calibration power level for transmission,

allowing a period of time for each of the plurality of wireless stations to transmit at least one calibration message at the commonly assigned calibration power level;

transmitting from each of the plurality of wireless stations at least one calibration message on the assigned carrier at the commonly assigned calibration power level;

receiving from each of the plurality of wireless stations information indicating transmissions from other ones of the plurality of wireless stations that they received and the receive power level of each of these received transmissions; and

using the received information to map the receive power levels and associated transmitting and receiving wireless stations.

20. The method according to claim 19 wherein the multi-carrier communication system is a non-overlaid communication system.

21. The method according to claim 19, wherein:

the multi-carrier communication system operates on a single frequency channel; and

the multi-carrier communication system subdivides the single frequency channel to form all available carriers.

22. A method of establishing overlaid communications in a multi-carrier communication system between a plurality of wireless stations each capable of communicating on less than all carriers in the multi-carrier communication system comprising the steps of:

providing each of the plurality of wireless stations capable of performing overlaid communications in the multi-carrier communication system a message which includes an assigned carrier and a commonly assigned calibration transmit power level for transmission,

allowing a period of time for each of the plurality of wireless stations to transmit at least one calibration message on the assigned carrier at the commonly assigned calibration power level;

transmitting from each of the plurality of wireless stations at least one calibration message on the assigned carrier at the commonly assigned calibration power level;

receiving from each of the plurality of wireless stations information indicating transmissions from other ones of the plurality of wireless stations that they received and the receive power level of each of these received transmissions; and

using the received information to map which ones of the plurality of wireless stations can communicate with other ones of the plurality of wireless stations on assigned carriers without substantially interfering with further ones of the plurality of wireless stations.

23. The method according to claim 22 wherein the steps of providing and receiving occur at the another wireless station.

24. The method according to claim 23 wherein the another wireless station is an access point.

25. The method according to claim 22 wherein it is determined that a first wireless station cannot communicate with a second wireless station at one of the available power levels at the same time without preventing a third wireless station from communicating.

26. The method according to claim 25 wherein it is determined that the first wireless station cannot communicate with the second wireless station at one of the available power levels at the same time without saturating the third wireless station.

27. The method according to claim 22 wherein each of the plurality of wireless stations transmit during the period of time the calibration message containing therein an identifier of the transmitting wireless station and a transmit power level at which the calibration message is being transmitted.

28. The method according to claim 22 wherein the received calibration message from various ones of the transmitting wireless stations is collected at each receiving wireless station and used to obtain the information during the step of receiving.

29. The method according to claim 22 further including a transmission period during which the plurality of wireless stations communicate within constraints of the map.

30. The method according to claim 29 wherein during the transmission period, at least one pair of the plurality of wireless stations communicate such that an acknowledgement after a transmission is not used.

31. The method according to claim 22, wherein:

the multi-carrier communication system operates on a single frequency channel; and

the multi-carrier communication system subdivides the single frequency channel to form all available carriers.