GPS Software Receivers - Fundamentals of Global Positioning System Receivers: A Software Approach - page 219

e=1/298.257223563;
Ltemp=Lc;
erro1=1;
while erro1>1e-6;
L=Lc+e*sin(2*Ltemp);
erro1=abs(Ltemp-L);
Ltemp=L;
end
Lflp=L*180/pi;
re=6378137;
h=rsp-re*(1-e*(sin(L)^2));
upos = [xuser yuser zuser bias rsp Lflp lsp h]';