I have the following optimization problem and I am trying to check for its convexity.linkAs per the definition of convexity, a continuous twice differentiable function is convex ON a convex set, iff the hessian is positive semi definite on the interior of the convex set.The feasible region where I am trying to check for its convexity its convexity is defined by..B, N, sigma are constants B = 20000N = 50sigma = 3.7678e-17w, p are variables(vectors of K elements)w can vary from 1 to 50p, 0 to 46 in dbm(unit of power..)I have to convert in into watt before using itp in watt = (10^(p in dbm/10))/1000.The hessian comes out to be indefinite for MANY of the feasible points..But I am not sure if I am right. Is the problem CONVEX, can any one check please..? 
Convexity Check
optimization