function [p,iter] = approxPAimpCSI(ghat,gbar,g0,pguess)
if ghat+gbar<g0
  p=0;
else
  [p,fval,exitflag,output] = fzero(@(x) PowerImperfectCSIApprox(x,ghat,gbar,g0),pguess);
  iter = output.iterations
end;