United States Patent 6,625,203
De , et al. September 23, 2003
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Fast joint detection
Abstract
K data signals are transmitted over a shared spectrum in a code division multiple access communication system. A combined signal is received and sampled over the shared spectrum. The combined signal has the K transmitted data signals. A combined channel response matrix is produced using the codes and impulse responses of the K transmitted data signals. A block column of a combined channel correlation matrix is determined using the combined channel response matrix. Each block entry of the block column is a K by K matrix. At each frequency point k, a K by K matrix .LAMBDA..sup.(k) is determined by taking the fourier transform of the block entries of the block column. An inverse of .LAMBDA..sup.(k) is multiplied to a result of the fourier transform. Alternately, forward and backward substitution can be used to solve the system. An inverse fourier transform is used to recover the data from the K data signals.
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Inventors: De; Parthapratim (Plainview, NY); Pan; Jung-Lin (Selden, NY); Zeira; Ariela (Huntington, NY)
Assignee: InterDigital Technology Corporation (Wilmington, DE)
Appl. No.: 037710
Filed: December 31, 2001
Current U.S. Class: 375/147; 370/342
Intern'l Class: H04B 014/00; H04B 014/08
Field of Search: 375/147,146,150,340,349,148 370/210,211,335,320,342,441 342/378
