Secure Information Transmissions in Wireless-Powered Cognitive Radio Networks for Internet of Medical Things

Algorithm 1

Optimal secure beamforming design.

	Initialize and ; define as a large positive real number; and are all small positive real numbers as the iterative steps for one-dimension search
1	for a given do S1-S4
2	S1: given , then solve problem (P3) and derive the optimal solution by utilizing CVX tools
3	S2: obtain optimal through the following procedures
4	if and , then
5	The optimal solution for problem (P3) is
6	else
7	Reconstruct an optimal solution for problem (P3) with and based on equation (21)
8	end if
9	S3: let when and then go to S1-S2
10	S4: choose the optimal solution from equation (22) and derive optimal secure beamforming vectors by performing EVD
11	end for
12	Update and S1-S4
	Choose the optimal solution based on equation (23)