x = [2.5, 2.7, 2.8, 3];
y = [0.00525, 0.000125, 0.0000125, 0.000000125];
plot(x, log10(y), 'r-');
axis([0, 12, -10, 0]);
grid
hold on
EbNo = 0:0.01:10
EbNoDecimal= 10.^(EbNo./10);%%將信噪比化為非dB表示
H = 0.5*erfc(sqrt(EbNoDecimal));
%%Q函數(shù)定義：1/2*erfc(sqrt(EbNo))并套用BPSK誤碼率公式
% semilogy(EbNo,H,'-b*');
plot(EbNo, log10(H), 'b-');


a = [4.3, 5, 6.5, 7.5];
b = [0.010383626489811611, 0.002158624887863642, 0.00000153400024544004, 0.000000000954896541];
plot(a, log10(b), 'm-.');