mirror of
https://github.com/saitohirga/WSJT-X.git
synced 2024-11-23 04:38:37 -05:00
2c17544f3f
git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/WSJT/trunk@1 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
20 lines
454 B
Fortran
20 lines
454 B
Fortran
subroutine lpf1(data,n,nz)
|
|
|
|
C Half-band lowpass filter and decimate by 2.
|
|
|
|
real data(n)
|
|
|
|
nz=n/2 -10
|
|
do i=1,nz
|
|
j=2*i+8
|
|
data(i)=0.047579*(data(j-9)+data(j+9))
|
|
+ - 0.073227*(data(j-7)+data(j+7))
|
|
+ + 0.113449*(data(j-5)+data(j+5))
|
|
+ - 0.204613*(data(j-3)+data(j+3))
|
|
+ + 0.633339*(data(j-1)+data(j+1))
|
|
+ + data(j)
|
|
enddo
|
|
return
|
|
end
|
|
|