gmsk.m

完成GMSK信号调制

function [I,Q,thita,phase] = gmsk(data,phase_init)

BT = 0.3;
h = 0.5;
T = 60/(13*8*1000*156.25);%s
len = 60/(13*8*1000);%一个时隙的长度
sample_rate = 8;
filter_order = 41;%8x滤波器阶数
phase_init = 0;

Rb = 1/T;
B = BT / T;
k = 0:T:len;
k1 = 0:T/sample_rate:len;
delta = sqrt(log(2))/(2*pi*BT);
alpha = (1/B) * sqrt(log(2)/2);
phase = phase_init;

len = length(data);
temp = [0,data(1:len-1)];
diffdata = xor(data,temp);

ambipolar_data = 1-2*diffdata;

[gmsk_I,gmsk_Q,thita,phase] = GMSK_conv(ambipolar_data,T,sample_rate,filter_order,phase);

start = ceil(filter_order/2) - 1;

I = gmsk_I(start+1:start+len*sample_rate);
Q = gmsk_Q(start+1:start+len*sample_rate);

stop = 1;