摘要 |
To realize a GDFE precoder for multi-user MIMO systems, which significantly reduces the computational cost while resulting in no capacity loss, one method comprises computing an effective UL channel matrix HUL using one of two methods HUL=HDLH, or HUL=[(Pt/Nt)HDLHHDL+I]−1/2HDLH; extracting Hk from HUL; computing a singular value decomposition of the DL channel between the BS and kth UT, Hk, for all K UTs, Hk=UkSkVkH; extracting all singular values as s=[diag(S1), . . . , diag(SK)]; extracting a vector ŝ from s by choosing first utmost Nt largest non-zero singular values of s; sorting elements in ŝ in decreasing order; performing water-filling to allocate power and obtain a diagonal matrix &Ggr;k representing power allocations corresponding to the singular values of the kth UT; computing an UL covariance matrix for each UT as Φk=Uk&Ggr;kUkH; and obtaining an overall input covariance matrix D for the equivalent UL channel.
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