Method used for detecting symbol in communication signal

Abstract

The method relates to a symbol detection method. The method includes receiving at least one communication signal y transmitted in a wireless channel H and receiving a prior LLR of a channel input x; calculating a soft symbol estimate [Mu] and a variance D of the channel input x on the basis of the LLR of the channel input x; using a first filter and the filtered soft symbol estimate [Mu] to filter and interference eliminate the received signal y so as to obtain filtered and interference eliminated reception signal; estimating a mean square error (MSE) matrix B of the filtered and interference eliminated reception signal; calculating the optimum matrix Gopt used for a BCJR algorithm on the basis of the MSE estimation B; using a second filter to filter the filtered and interference eliminated reception signal to obtain an input signal r used for the BCJR algorithm; and introducing the input signal r to the BCJR algorithm.

Description

technical field [0001] The method relates to a method for detecting symbols carried in communication signals. Furthermore, the invention relates to a detection device, a computer program and a computer program product. Background technique [0002] The prior art mentions an arbitrary linear channel whose formula is y=Hx+n, where H is an MxN matrix of channel gain, x is an Nx1 vector of channel input, and n is an Mx1 vector of IID complex Gaussian noise variables, These variables have mean 0 and variance matrix N 0 I. [0003] The problem that interests us is soft-in and soft-out detection of vector x. It is easy to solve this problem by the Bahl-Cook-Jelinke-Raviv (BCJR) algorithm, but the complexity of each detected symbol is O(|Ω| K ), where Ω is the modulation letter and K is the memory of the channel matrix H. Said memory is the central theme, and we shall next define what this term actually means. We perform a QL factorization on the channel matrix H, so write H=Q...

AI Technical Summary

Problems solved by technology

[0015] There will be problems if the channel memory K is too la

Images