Patent ID: 7542743

Claim:
A method comprising: performing a linear transformation by use of a transformation matrix W to convert a multiple-input-multiple-output communication channel matrix H into a transformed channel matrix WH and a receive signal vector r into a transformed receive signal vector Wr that allows a Euclidean distance metric to be represented in a partitioned form, wherein the Euclidean distance metric has a first partitioned term that depends on a candidate value x 0 for a signal transmitted from a first transmitting antenna and a second partitioned term that depends on x 0 and a candidate value x 1 for a signal transmitted from a second transmitting antenna; initializing recursion values corresponding to terms of the first and second partitioned terms for an initial x 0 ; using the recursion values to compute a local minimum Euclidean distance metric for the initial x 0 over all possible candidate values x 1 , wherein an implicit search over all candidate values x 1 is provided by a slicer operation operating on the second partitioned term; performing an ordered search over all x 0 values by recursively updating the recursion values and calculating subsequent local minimum Euclidean distance metrics for each value of x 0 ; selecting a first global minimum from the local minimum Euclidean distance metrics found for x 0 values for each bit position, k, of a corresponding K-bit binary representation of x 0 , where bit position k exhibits a first possible bit value, and selecting a second global minimum from the local minimum Euclidean distance metrics found for x 0 values for each bit position k, where bit position k exhibits a second possible bit value; and using a comparison of the first and second global minimum Euclidean distance metrics for each bit position k to determine a maximum likelihood information L k for each bit position k.