Beamforming using predefined spatial mapping matrices

1. A method comprising:

storing, in a memory, predefined spatial mapping matrices useful for transmitting data packets to a receiver;

iteratively transmitting one or more of the data packets to the receiver, each act of transmitting using a different one of the predefined spatial mapping matrices stored in the memory;

receiving, from the receiver, channel estimates responsive to iteratively transmitting the one or more data packets;

selecting, based on the received channel estimates, one of the predefined spatial mapping matrices stored in the memory for use in transmitting one or more additional data packets to the receiver; and

selecting another one of the predefined spatial mapping matrices when a reception quality metric associated with the one or more additional data packets transmitted to the receiver fails to meet a reception quality metric threshold.

2. The method as described in claim 1 , wherein the reception quality metric is a data rate associated with the one or more additional data packets and the reception quality metric threshold is a minimum data rate.

3. The method as described in claim 1 , wherein the other one of the predefined spatial mapping matrices is a second predefined spatial mapping matrix and the method further comprises altering the reception quality metric threshold effective to cause selection of at least a third one of the predefined spatial mapping matrices for subsequent data transmissions.

4. The method as described in claim 1 further comprising selecting, for subsequent data transmissions, different ones of the predefined spatial mapping matrices until a reception quality metric associated with the subsequent data transmissions meets the reception quality metric threshold.

5. The method as described in claim 1 , wherein the one or more data packets are transmitted using the different predefined spatial mapping matrices without channel training.

6. The method as described in claim 1 , wherein the acts of iteratively transmitting and receiving are performed in accordance with the IEEE 802.11a standard, IEEE 802.11g standard, IEEE 802.11n standard, IEEE 802.16 standard, or 3 rd generation partnership project long term evolution (GPP LTE) standard.

7. The method as described in claim 1 , wherein the acts of iteratively transmitting and receiving are implemented using an orthogonal frequency division multiplexing (OFDM) modulation scheme.

8. One or more non-transitory computer-readable memory devices storing executable instructions that, responsive to execution by a processor, implement a communication controller configured to:

iteratively transmit one or more data packets to a receiver, each act of transmitting using a different one of a set of predefined spatial mapping matrices;

receive, from the receiver, channel estimates responsive to the one or more data packets iteratively transmitted to the receiver;

select, based on the received channel estimates, one of the predefined spatial mapping matrices from the set of predefined spatial mapping matrices for use in transmitting one or more additional data packets to the receiver; and

select another one of the predefined spatial mapping matrices when a reception quality metric associated with the one or more additional data packets transmitted to the receiver fails to meet a reception quality metric threshold.

9. The one or more non-transitory computer-readable memory devices of claim 8 , wherein the reception quality metric is a data rate associated with the one or more additional data packets and the reception quality metric threshold is a minimum data rate.

10. The one or more non-transitory computer-readable memory devices of claim 8 , wherein the other one of the predefined spatial mapping matrices is a second predefined spatial mapping matrix and the communication controller is further implemented to alter the reception quality metric threshold effective to cause selection of at least a third one of the predefined spatial mapping matrices for subsequent data transmissions.

11. The one or more non-transitory computer-readable memory devices of claim 10 , wherein the communication controller is further implemented to alter the reception quality metric threshold such that each one of the of the predefined spatial mapping matrices is iteratively selected for transmission of at least one data packet of the subsequent data transmissions.

12. The one or more non-transitory computer-readable memory devices of claim 11 , wherein the communication controller is further implemented to:

monitor, during the subsequent data transmissions, reception quality metrics associated with each one of the of the predefined spatial mapping matrices; and

select, based on the monitored reception quality metrics, an optimal predefined spatial mapping matrix.

13. The one or more non-transitory computer-readable memory devices of claim 8 , wherein the one or more data packets are transmitted using the set of predefined spatial mapping matrices without channel training.

14. The one or more non-transitory computer-readable memory devices of claim 8 , wherein the communication controller is configured for communication in a 60 GHz wireless system.

15. The one or more non-transitory computer-readable memory devices of claim 8 , wherein the communication controller is embodied on a wireless device that communicates via an orthogonal frequency division multiplexing (OFDM) modulation scheme.

16. An apparatus comprising:

one or more antennas configured for directional transmissions;

memory configured to maintain a codebook having predefined spatial mapping matrices useful for beamforming; and

a transmission controller configured to:

iteratively transmit, via the one or more antennas, data packets in different directions using the predefined spatial mapping matrices;

receive channel estimates from a receiver responsive to one or more of the data packets iteratively transmitted to the receiver;

select, based on the received channel estimates, one of the predefined spatial mapping matrices for communicating one or more additional data packets with the receiver via the one or more antennas; and

select another one of the predefined spatial mapping matrices when a reception quality metric associated with the one or more additional data packets transmitted to the receiver fails to meet a reception quality metric threshold.

17. The apparatus as recited in claim 16 , wherein the reception quality metric is a data rate associated with the one or more additional data packets and the reception quality metric threshold is a minimum data rate.

18. The apparatus as recited in claim 16 , wherein the transmission controller is further configured to, based on spatial mapping matrix feedback received from the receiver, select an optimal one of the predefined spatial mapping matrices for subsequent data transmissions to the receiver.

19. The apparatus as recited in claim 16 , wherein the apparatus is embodied, in whole or part, as a cellular base station, wireless network access point, or wireless network router.

20. The apparatus as recited in claim 16 , wherein the apparatus is configured to communicate in accordance with the IEEE 802.11 a standard, IEEE 802.11g standard, IEEE 802.11n standard, IEEE 802.16 standard, or 3 rd generation partnership project long term evolution (GPP LTE) standard.