%?This?code?is?to?plot?receiver?operating?characteristic?curve?for?simple?energy
%?detection?when?the?primary?signal?is?real?Gaussian?signal?and?noise?is
%?addive?white?real?Gaussian.?Here?the?threshold?is?available
%?analytically.
%?Code?written?by:?Sanket?Kalamkar?Indian?Institute?of?Technology?Kanpur
%?India.

%%?以下代碼繪制在虛警概率一定時(shí)，檢測(cè)概率和信噪比之間的關(guān)系曲線稱為檢測(cè)器的檢測(cè)性能曲線
clc
close?all
clear?all
L?=?1000;?????????????????????????????????????????????%?The?number?of?samples
snr?=?0.01:0.01:10;
Pf?=?10e-4;???????????????????????????????????????????%?Pf?=?Probability?of?False?Alarm?虛警概率確定
%%?Simulation?to?plot?SNR?vs.Probability?of?Detection?（Pd）
for?m?=?1:length（snr）
????i?=?0;
????thresh?=?（qfuncinv（Pf）./sqrt（L））+?1;??????????????%?Theoretical?value?of?Threshold?refer?Sensing-Throughput?Tradeoff?for?Cognitive?Radio?Networks?Y.?C.?Liang
????for?kk?=?1:5000???????????????????????????????????%?Number?of?Monte?Carlo?Simulations（https://cn.mathworks.com/discovery/monte-carlo-simulation.html）
????????n?=?randn（1L）;???????????????????????????????%?AWGN?noise?with?mean?0?and?variance?1
????????s?=?sqrt（snr（m））.*randn（1