36 lines
998 B
Fortran
36 lines
998 B
Fortran
subroutine spec4(c,s,savg)
|
|
|
|
parameter (KK=84) !Information bits (72 + CRC12)
|
|
parameter (ND=84) !Data symbols: LDPC (168,84), r=1/2
|
|
parameter (NS=12) !Sync symbols (3 @ 4x4 Costas arrays)
|
|
parameter (NR=2) !Ramp up/down
|
|
parameter (NN=NR+NS+ND) !Total symbols (98)
|
|
parameter (NSPS=2688/84) !Samples per symbol (32)
|
|
parameter (NZ=NSPS*NN) !Samples in baseband waveform (3760)
|
|
parameter (NFFT=2*NSPS,NH=NSPS)
|
|
|
|
complex c(0:NZ-1)
|
|
complex c1(0:NFFT-1)
|
|
real s(0:NH,NN)
|
|
real savg(0:NH)
|
|
|
|
fs=12000.0/84.0
|
|
df=fs/NFFT
|
|
savg=0.
|
|
do j=1,NN
|
|
ia=(j-1)*NSPS
|
|
ib=ia + NSPS-1
|
|
c1(0:NSPS-1)=c(ia:ib)
|
|
c1(NSPS:)=0.
|
|
call four2a(c1,NFFT,1,-1,1)
|
|
do k=1,NSPS
|
|
s(k,j)=real(c1(k))**2 + aimag(c1(k))**2
|
|
enddo
|
|
savg=savg+s(0:NH,j)
|
|
enddo
|
|
s=s/NZ
|
|
savg=savg/(NN*NZ)
|
|
|
|
return
|
|
end subroutine spec4
|