I can’t run the program because you haven’t provided ricianCh.
For those who don’t have the Signal Processing Toolbox, such as myself, db2pow(x) = 10*log10(x).
I don’t see how the iterations are supposed to differ, because it appears that the loop variable, ite, is not used in the for loop, except for display.
You haven’t shown the solver or CVX for even one iteration. You should start by carefully examining and analyzing that.
If you have Mosek available as solver, use that; otherwise follow the instructions at CVXQUAD: How to use CVXQUAD's Pade Approximant instead of CVX's unreliable Successive Approximation for GP mode, log, exp, entr, rel_entr, kl_div, log_det, det_rootn, exponential cone. CVXQUAD's Quantum (Matrix) Entropy & Matrix Log related functions
I deleted an earlier topic by you which appeared to be essentially the same as this topic. In the future, please edit your existing topic, rather than creating an additional topic.