sigma=<0..∞>  factor for the parametric windows:


nT=<1,0..∞> 


Win=<1:29>  windowing functions. The marked* ones are parametric and make use of sigma , while the doublemarked** ones are a function of As :
a[0:4] , are hidden)
1+20 terms, five decimals (not digits) accurate for As=120dB )
.sub file for ".subckt FIR_FS ", then locate the fspl(x) function and then add the frequency domain response for the interval <0..π> .


Choice=<0:6>  the possible additional functions/combinations with Win :
3 = raised cosine 4 = (square) rootraised cosine
nT , while SPS (oversampling) and beta (rolloff) are calculated from BWp and BWs :SPS=round[f0/(BWs+BWp)] beta=(BWsBWp)/(BWs+BWp)Notes:
6 = Hilbert transformer This allows for windowing with functions from Choice=<2:6> . (FIR, FIRx, FIR2)For FIR_FS, Choice is only used to determine the type in the table below.


sim  s  total .TRAN simulation time, needs test=1 . E.g.: if the command is .TRAN 25m , then sim=25m . (optional) 

test=<0,1>  0 disables, 1 enables pins 0.2 and 0.3 . (optional) 

SH=<0,1>  disables/enables (forces) a real sample&hold behaviour. There are two scenarios:


Fact=<k:k>  for k=<1:32> :


f0  Hz  the sampling frequency. For interpolation/decimation, f0 is set to match the input's frequency and BWp, BWs are calculated according to the specified f0 .E.g. for input of f0=1kHz and Fact=4 ⇒ f0=1k and BWp, BWs are calculated for 1kHz sampling frequency.For external synchronization set SH=1 , f0=−f0 while the external clock must have the output's sampling rate, CLK=f0*Fact^{sgn(Fact)} .Examples:


fc  Hz  the center frequency. (also see the description for f0).  
BWp  Hz  the passband bandwidth. (also see the description for f0).  
BWs  Hz  the stopband bandwidth. (also see the description for f0).  
See the graphs on how to get the desired function with fc , BWp and BWs . 

G=<∞..∞>  gain, linear.  
As  dB  stopband attenuation, positive value.  
N=<0:257> N=<0:1025> (FIRx, only) 
Choice and N :


Hidden:  
a0 a1 a2 a3 a4  the five terms for the general cosine window.  
td, tr  s  delay and rise times of the clock, effective if SH=1 ; default values are tr=f0/1000 and td=0 . 