ca_mul_d.m

gps信号模拟器中用产生的ca码扩频已有的d码

function CA_MUL_DATA=ca_mul_d();
DataCode = fGenerateNavigationData();
Lc=20460;
%repeated_DataCode分配空间
repeated_DataCode = zeros(1,1500*1023*20,'int8');
%拉长1500bit导航电文，方便与ca码相乘
for i=1:1500
    for j=1:Lc
        repeated_DataCode((i-1)*20460+j)=DataCode(i);
    end
end


cacode = fGenerateCAcode();
%重复cacode 1500*1023*20次
cacode = int8(cacode);
cacode = [cacode cacode cacode cacode cacode cacode cacode cacode cacode cacode];
cacode = [cacode cacode cacode cacode cacode cacode cacode cacode cacode cacode];
cacode = [cacode cacode cacode cacode cacode cacode cacode cacode cacode cacode];
cacode = [cacode cacode cacode cacode cacode cacode cacode cacode cacode cacode];
cacode = [cacode cacode cacode];
% ca码和1500bit的D码相乘
CA_MUL_DATA = cacode.*repeated_DataCode;



% ind1=find(CA_MUL_DATA==0);
% ind2=find(CA_MUL_DATA==1);
% CA_MUL_DATA(ind1)=ones(1,length(ind1));
% CA_MUL_DATA(ind2)=-ones(1,length(ind2));

CA_MUL_DATA1=CA_MUL_DATA(1:1023000);