Method and device for operating a precoded mimo system

Abstract

A method is provided for generating precoder data ( 600 ), comprising: obtaining transmit power data indicative of a transmit power of a plurality of multiple-input/multiple-output signals ( 610 ); obtaining signal quality data, the signal quality data including at least one measure of a quality of the plurality of multiple-input/multiple-output signals ( 620, 630 ); obtaining channel data with respect to a wireless channel, the channel data including a measure of respective channel parameters of each of a plurality of channel paths in the wireless channel ( 620, 630 ); constraining one or more system performance parameters ( 640 ); and determining first and second precoder diagonal values (w A and w B ) based on the signal quality data, the transmit power data, the channel data, and the one or more constrained system performance parameters ( 650 ).

1 . A method for generating precoder data, comprising:
 obtaining transmit power data indicative of a transmit power of a plurality of multiple-input/multiple-output signals;   obtaining signal quality data, the signal quality data including at least one measure of a quality of the plurality of multiple-input/multiple-output signals;   obtaining channel data with respect to a wireless channel, the channel data including a measure of respective channel parameters of each of a plurality of channel paths in the wireless channel;   constraining one or more system performance parameters; and   determining first and second precoder diagonal values based on the signal quality data, the transmit power data, the channel data, and the one or more constrained system performance parameters.   
     
     
         2 . The method of  claim 1 , further comprising:
 receiving the plurality of multiple-input/multiple-output signals from a remote device over the wireless channel,   wherein the obtaining of the signal quality data is performed by detecting the signal quality data based on the plurality of multiple-input/multiple-output signals, and   wherein the obtaining of the channel data is performed by detecting the channel data based on the plurality of multiple-input/multiple-output signals.   
     
     
         3 . The method of  claim 1 , wherein the constraining of the one or more system performance parameters is performed by constraining signal-to-noise-plus-interference ratios of two symbol pairs contained in the plurality of multiple-input/multiple-output signals. 
     
     
         4 . The method of  claim 3 , wherein the constraining of the one or more system performance parameters is performed by equating the signal-to-noise-plus-interference ratios of the two symbol pairs contained in the plurality of multiple-input/multiple-output signals. 
     
     
         5 . The method of  claim 1 , wherein during the determining operation, the first and second precoder diagonal values are selected from a limited set of possible values. 
     
     
         6 . The method of  claim 1 , wherein during the determining operation, the first and second precoder diagonal values are selected from a set constellation of vector values. 
     
     
         7 . The method of  claim 1 , further comprising transmitting the first and second precoder diagonal values to a remote device. 
     
     
         8 . The method of  claim 1 , wherein the signal quality data comprises the noise variance of the plurality of multiple-input/multiple-output signals. 
     
     
         9 . The method of  claim 1 , further comprising performing minimum mean square estimation operation successive interference cancellation operation on the plurality of multiple-input/multiple-output signals. 
     
     
         10 .- 15 . (canceled) 
     
     
         16 . A multiple-input/multiple-output receiver, comprising:
 a receiver circuit configured to receive a plurality of multiple-input/multiple-output signals from a remote device over a wireless channel, the wireless channel including a plurality of channel paths;   a channel analyzing circuit configured to detect signal quality data and channel data from the plurality of multiple-input/multiple-output signals, the signal quality data including at least one measure of a quality of the plurality of multiple-input/multiple-output signals, and the channel data including a measure of respective channel properties of each of the plurality of channel paths; and   a precoder diagonal value calculator configured to determine first and second precoder diagonal values based on the signal quality data, the channel data, a transmit power of the plurality of multiple-input/multiple-output signals, and one or more constrained system performance parameters.   
     
     
         17 . The multiple-input/multiple-output receiver of  claim 16 , wherein the multiple-input/multiple-output receiver is a part of one of a (3×L) multiple-input/multiple-output system and a (4×L) multiple-input/multiple-output system, and wherein L is an integer greater than or equal to 2. 
     
     
         18 . The multiple-input/multiple-output receiver of  claim 16 , wherein the signal quality data comprises the noise variance of the plurality of multiple-input/multiple-output signals. 
     
     
         19 . The multiple-input/multiple-output receiver of  claim 16 , wherein the receiver is implemented using an integrated circuit. 
     
     
         20 . The multiple-input/multiple-output receiver of  claim 16 , wherein the precoder diagonal value calculator determines the first and second precoder diagonal values by selecting them from a limited set of possible scalar or vector values. 
     
     
         21 . The multiple-input/multiple-output receiver of  claim 16 , wherein the precoder diagonal value calculator determines the first and second precoder diagonal values by generating a vector value. 
     
     
         22 . The multiple-input/multiple-output receiver of  claim 16 , wherein the one or more constrained system performance parameters are signal-to-noise-plus-interference ratios of two symbol pairs contained in the plurality of multiple-input/multiple-output signals. 
     
     
         23 . The multiple-input/multiple-output receiver of  claim 16 , wherein the receiver is further configured to perform a minimum mean square estimation successive interference cancellation process on the plurality of multiple-input/multiple-output signals from the remote device. 
     
     
         24 . A wireless device, comprising:
 a wireless interface adapted to receive a plurality of multiple-input/multiple-output (MIMO) signals from a transmitting device over a wireless channel;   a first module configured to obtain channel data with respect to a wireless channel, the channel data comprising information based on one or more respective channel parameters of each of a plurality of channel paths in the wireless channel; and   a second module configured to provide the obtained channel data to the transmitting device;   wherein the provided channel data is configured to enable the transmitting device to determine a first and second precoder diagonal values therefrom.   
     
     
         25 . The wireless device of  claim 24 , wherein the channel data comprises the noise variance of the plurality of MIMO signals. 
     
     
         26 . The wireless device of  claim 24 , wherein first module is adapted to obtain channel data based on a known series of bits. 
     
     
         27 . A method for generating precoder data for use in a wireless apparatus, the method comprising:
 obtaining transmit power data relating to a transmit power of a plurality of multiple-input/multiple-output signals;   obtaining signal quality data including at least one measure of a quality of the plurality of multiple-input/multiple-output signals;   obtaining channel data related to a wireless channel, the channel data including a measure of respective channel parameters of each of a plurality of channel paths in the wireless channel; and   determining at least one precoder diagonal value based at least on the signal quality data, the transmit power data, and the channel data.   
     
     
         28 . Apparatus capable of receiving multiple-input/multiple-output signals, the apparatus comprising:
 a receiver circuit configured to receive a plurality of multiple-input/multiple-output signals from a remote device over a wireless channel, the wireless channel including a plurality of channel paths;   a channel analyzing circuit configured to detect signal quality data and channel data from the plurality of multiple-input/multiple-output signals, the signal quality data including at least one measure of a quality of the plurality of multiple-input/multiple-output signals, and the channel data including at least one measure of respective channel properties of each of the plurality of channel paths; and   apparatus in communication with the channel analyzing circuit and configured to determine first and second precoder values based at least in part on the signal quality data, the channel data, and a transmit power of the plurality of multiple-input/multiple-output signals.