channstatlog.m

载波平滑仿真程序,用matlab编写 经验证十分有效果

%% -----------------------------------------------------------------------------
%%   Title   : channstatlog.m
%%   Project : GPS & Galieo receiver realization
%%             Laboratoire de communication et d'int間ration
%%             de la micro閘ectronique (LACIME)
%%             蒫ole de Technologie Sup閞ieure (蒚S)
%%             Montr閍l, Qu閎ec
%%
%%   Author  : Bruno Sauriol
%%   Date    : 08/05/2007
%%
%%   Description :
%%
%%     The purpose of this script is to extract the data
%%     from a binary channel status log. The data is returned
%%     in 10 NxM arrays, where M is the total number of receiver's
%%     channel and N is the number of samples.
%%     The arrays returned are as follow:
%%      [t,Nav,Sync,CPU,PRN,C_N0,Lvl,Fail,Lock,Bad,Health,tval,SVt,SVw,NC,SC,TLC,TRC] = channstatlog(filename)
%%              t  Local clock (bias to GPS time always < 1 sec.)
%%            Nav  Navigation solution has converged flag
%%           Sync  Embedded CPU & PC are in sync flag
%%            CPU  Embedded CPU load (%)
%%            PRN  Active PRN # for each channel
%%           C_N0  C/N0 for each channel (dB.Hz)
%%            Lvl  Channels' acquisition/tracking level
%%           Fail  Channels' acquisition failure counter
%%           Lock  Channels' PLL locked flag
%%            Bad  Current SV is bad flag (do not include in nav. solution)
%%         Health  Current SV health summary (1 = bad health)
%%           tval  Current SV's gps time and week are valid flag
%%           SVt   Current SV's gps time (seconds)
%%           SVw   Current SV's gps week (modulo 1024)
%%           NC    Normalize coeffcient for multipath estimation
%%           SC    symmetric coefficient for multipath estimation
%%           TLC   theoritic left coefficient for multipath estimation
%%           TRC    theoritic rigth coefficient for multipath estimation
%%
%%
%% -----------------------------------------------------------------------------
%%   modification history :
%% -----------------------------------------------------------------------------
%%  Version  Mod. Date      Author and description
%%
%% -----------------------------------------------------------------------------
function [t,Nav,Sync,CPU,PRN,C_N0,Lvl,Fail,Lock,Bad,Health,tval,SVt,SVw,NC,SC,TLC,TRC] = channstatlog(filename)

    fid = fopen(filename,'r') ; % Opens log file
    fseek(fid,0,'eof');         % Gets file length
    len = ftell(fid);           %
    fseek(fid,0,'bof');         % Returns to file beginning
    n = fread(fid,1,'uint32');  % Reads number of channels
    len = (len-4)/(62*n+18) - mod(len-4,62*n+18);
    t = zeros(len,1);
    Nav = uint8(zeros(len,1));
    Sync = uint8(zeros(len,1));
    CPU = zeros(len,1);
    PRN = uint32(zeros(len,n));
    C_N0 = zeros(len,n);
    data = uint8(zeros(len,n*6));
    SVw = uint32(zeros(len,n));
    SVt = zeros(len,n);
    for i = 1:len
        t(i) = fread(fid,1,'double');
        Nav(i) = fread(fid,1,'uint8');
        Sync(i) = fread(fid,1,'uint8');
        CPU(i) = fread(fid,1,'double');
        for m = 1:n
            PRN(i,m) = fread(fid,1,'uint32');
            C_N0(i,m) = fread(fid,1,'double');
            data(i,(m-1)*6+1:m*6) = fread(fid,6,'uint8');
            SVw(i,m) = fread(fid,1,'uint32');
            SVt(i,m) = fread(fid,1,'double');
            NC(i,m)= fread(fid,1,'double');
            SC(i,m)= fread(fid,1,'double');
            TLC(i,m)= fread(fid,1,'double');
            TRC(i,m)= fread(fid,1,'double');
        end
    end
    fclose(fid);
    Lvl = uint8(zeros(len,n));
    Fail = uint8(zeros(len,n));
    Lock = uint8(zeros(len,n));
    Bad = uint8(zeros(len,n));
    Health = uint8(zeros(len,n));
    tval = uint8(zeros(len,n));
    for i = 0:n-1
        Lvl(:,i+1) = data(:,1+i*6);
        Fail(:,i+1) = data(:,2+i*6);
        Lock(:,i+1) = data(:,3+i*6);
        Bad(:,i+1) = data(:,4+i*6);
        Health(:,i+1) = data(:,5+i*6);
        tval(:,i+1) = data(:,6+i*6);
    end