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1|2. x即为功率分配方法. 而当c3<0、c4>0时,取x=1. 附录2 由L可知 =+× + 令k1=、k2=、b0=, 则应用拉格朗日乘法数,取 F=1/L+λ(P-P1-P2)= (k2/P2+b0)(k1/P1+b0)+λ(P-P1-P2) F/P1=(k2/P2+b0)k1(-1/P21)-λ=0 F/P2=(k1/P1+b0)k2(-1/P22)-λ=0(附1) 由式(附1)得 (k2/P2+b0)k1/P21=(k1/P1+b0)k2/P22 代入P2=P-P1,化简整理得 b0-b0P21-2b0P+1P1+ b0P+1P=0 P1=P/1+P+1[]b0P+1 ==+2 令L(1)=+,由=0,可得cot?θ=;再根据cot?θ求预编码向量,求取b1、b2. |