gmsk_conv.m

完成GMSK信号调制

function [I,Q,thita,phase] = GMSK_conv(src,T,sample_rate,filter_order,phase_init)

h = 0.5;
BT = 0.3;

B = BT/T;
Rb = 1/T;

grfilter = gauss_rect_filter(B,filter_order,sample_rate,Rb);

sample_data = upsample(src,sample_rate);

w = conv(sample_data,grfilter);

th(1) = phase_init;
for index = 2:1:length(w)+1
    th(index) = th(index-1)+pi*h*w(index-1)*T/sample_rate;
end;

phase = th(index);
thita = th(2:length(w)+1);
I = cos(th(2:length(w)+1));
Q = sin(th(2:length(w)+1));