Channel assignment based on spatial strategies in a wireless network using adaptive antenna arrays

• US 7,702,336 B2
• Filed: 05/15/2009
• Issued: 04/20/2010
• Est. Priority Date: 03/28/2002
• Status: Expired due to Fees

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Trott, Mitchell D., Kasapi, Athanasios A., Sousa, Elvino S.
• Primary Examiner(s): PHAN, HUY Q
• Application Number:
  US12/467,132
• Publication Number:
  US 20090233614A1
• Time in Patent Office: 340 Days
• Field of Search: 455/450, 455/452.1, 455/452.2, 455/434, 455/509, 455/464, 455/453, 455/422.1, 455/562.1, 455/575.7
• US Class Current: 455/450
• CPC Class Codes: H04W 16/28 using beam steering
• CPC Class Codes: H04W 72/046 the resource being in the space domain, e.g. beams
• CPC Class Codes: H04W 72/54 based on quality criteria

Abstract

Channels are assigned based on co-spatial constraints in wireless network using spatial division multiple access. In one example, the invention includes assigning a co-spatial constraint to each of a plurality of conventional traffic communications channels of a base station, and receiving a request from a user terminal to communicate using a traffic communication channel of the base station. The invention further includes measuring a quality parameter of the request deriving a co-spatial constraint for the user terminal, assigning the user terminal co-spatial constraint to the user terminal, and assigning the user terminal to a traffic communication channels having a channel co-spatial constraint that is no less than the user terminal co-spatial constraint and that has no more assigned radios than permitted by the channel co-spatial constraint.

Claims

1. A method comprising:

assigning a co-spatial constraint to each of a plurality of conventional traffic communications channels of a base station, the channel co-spatial constraints comprising a limitation on the quantity of radios that can share the respective channel using spatial division multiple access;

receiving a request from a user terminal to communicate using a traffic communication channel of the base station;

measuring a quality parameter of the request received from the user terminal;

deriving a co-spatial constraint for the user terminal based on the quality parameter, the user terminal co-spatial constraint comprising a limitation on the quantity of additional radios with which the user can share a conventional traffic communications channel using spatial division multiple access;

assigning the user terminal co-spatial constraint to the user terminal; and

assigning the user terminal to one of the plurality of traffic communication channels having a channel co-spatial constraint that is no less than the user terminal co-spatial constraint and that has no more assigned radios than permitted by the channel co-spatial constraint.

2. The method of claim 1, wherein the other radios assigned to a channel have the same user terminal co-spatial constraint as the assigned user terminal.

3. The method of claim 1, wherein measuring the quality parameter comprises determining one or more of:

a distance to the user terminal;

a strength of the received signal;

a SNR of the received request, a SINR of the received request, a quality of service designation of the user terminal;

a mobility designation of the user terminal;

a mobility of the user terminal;

a Doppler shift of the request;

a Doppler spread of the request;

a velocity of the user terminal; and

an angle spread of the request.

4. The method of claim 1, further comprising transmitting a communications signal to the user terminal over the communications channel.

5. The method of claim 1, further comprising transmitting nulls to the user terminal corresponding to the other radios assigned to the same channel.

6. The method of claim 1, further comprising:

searching for a channel having a channel co-spatial constraint equal to the user terminal co-spatial constraint and having a number of assigned radios no more than the channel co-spatial constraint;

if a such a channel is not found, then searching for a channel having a channel co-spatial constraint that is less than the user terminal co-spatial constraint and having a number of assigned radios no more than the channel co-spatial constraint;

if such a channel is not found, then denying service to the user terminal; and

wherein assigning the user terminal comprises assigning the user terminal to the channel found by searching.

7. The method of claim 6, further comprising:

reassigning other radios to other channels;

after reassigning other radios, repeating searching for a channel having a co-spatial constraint equal to the user terminal co-spatial constraint and having no more assigned radios than permitted by the channel co-spatial constraint; and

assigning the user terminal to the found channel.

8. The method of claim 1, further comprising assigning a different channel co-spatial constraint to a channel having no more assigned radios than permitted by the user terminal co-spatial constraint and assigning the user terminal to the respective channel if no channel is available having a channel co-spatial constraint that is no less than the user terminal co-spatial constraint and that has no more assigned radios than permitted by the channel co-spatial constraint.

9. A machine-readable medium having stored thereon data representing instructions, which if executed by the machine, cause the machine to perform operations comprising:

assigning a co-spatial constraint to each of a plurality of conventional traffic communications channels of a base station, the channel co-spatial constraints comprising a limitation on the quantity of radios that can share the respective channel using spatial division multiple access;

receiving a request from a user terminal to communicate using a traffic communication channel of the base station;

measuring a quality parameter of the request received from the user terminal;

deriving a co-spatial constraint for the user terminal based on the quality parameter, the user terminal co-spatial constraint comprising a limitation on the quantity of additional radios with which the user can share a conventional traffic communications channel using spatial division multiple access;

assigning the user terminal co-spatial constraint to the user terminal; and

assigning the user terminal to one of the plurality of traffic communication channels having a channel co-spatial constraint that is no less than the user terminal co-spatial constraint and that has no more assigned radios than permitted by the channel co-spatial constraint.

10. The medium of claim 9, wherein the instructions further cause the machine to transmit nulls to the user terminal corresponding to the other radios assigned to the same channel.

11. The medium of claim 9, wherein the instructions further cause the machine to perform further operations comprising:

searching for a channel having a channel co-spatial constraint equal to the user terminal co-spatial constraint and having a number of assigned radios no more than the channel co-spatial constraint;

if a such a channel is not found, then searching for a channel having a channel co-spatial constraint that is less than the user terminal co-spatial constraint and having a number of assigned radios no more than the channel co-spatial constraint;

if such a channel is not found, then denying service to the user terminal; and

wherein assigning the user terminal comprises assigning the user terminal to the channel found by searching.

12. A communications device comprising:

a receiver to receive a request from a user terminal to communicate using a traffic communication channel of a base station; and

a processor communicatively coupled to the receiver to;

assign a co-spatial constraint to each of a plurality of conventional traffic communications channels of the base station, the channel co-spatial constraints comprising a limitation on the quantity of radios that can share the respective channel using spatial division multiple access;

measure a quality parameter of the request received from the user terminal;

derive a co-spatial constraint for the user terminal based on the quality parameter, the user terminal co-spatial constraint comprising a limitation on the quantity of additional radios with which the user can share a conventional traffic communications channel using spatial division multiple access;

assign the user terminal co-spatial constraint to the user terminal; and

assign the user terminal to one of the plurality of traffic communication channels having a channel co-spatial constraint that is no less than the user terminal co-spatial constraint and that has no more assigned radios than permitted by the channel co-spatial constraint.

13. The apparatus of claim 12, further comprising a transmitter to transmit a communications signal to the user terminal over the communications channel.

14. The apparatus of claim 13, wherein the transmitter further transmits nulls to the user terminal corresponding to the other radios assigned to the same channel.

15. A method comprising:

measuring a quality parameter of a signal received from a second radio at a first radio;

deriving a co-spatial constraint for the second radio based on the quality parameter, the co-spatial constraint comprising a limitation on the quantity of additional radios with which the second radio can share one of a plurality of conventional communications channels using spatial division multiple access;

assigning the co-spatial constraint to the second radio;

assigning the second radio to one of a plurality of traffic communication channels by first assigning the second radio to an unused channel, if available, and if not available then by second assigning the second radio to a channel to which only one other radio is already assigned, if available, and if not available then by third assigning the second radio to a channel to which only two other radios are already assigned, if available, wherein the number of other radios already assigned does not exceed the co-spatial constraint; and

sharing each traffic communication channel to which more than one radio is assigned using spatial division multiple access.

16. The method of claim 15, wherein the second radio is assigned to a channel to which at least one other radio is assigned and wherein the other assigned radios each have an assigned co-spatial constraint and wherein the co-spatial constraints of the other assigned radios are greater than or equal to that of the second radio.

17. The method of claim 15, further comprising assigning a co-spatial restraint to the channel to which the second radio is assigned based on the co-spatial constraint of the second radio.

18. The method of claim 15, wherein determining the quality parameter of the second radio comprises determining one or more of a distance of the second radio from the first radio, a strength of the received signal, a SNR of the received signal, a SINR of the received signal, a quality of service designation of the second radio, a mobility designation of the second radio, a mobility of the second radio, a Doppler shift of the received signal, a Doppler spread of the received signal, a velocity of the second radio, and an angle spread of the received signal.

19. The method of claim 15, wherein determining the quality parameter, and selecting the communications channel are performed by the first radio, the first radio being comprised of a base station and the second radio being comprised of one of a plurality of subscriber units.