[daip] CLCAL problem.

[Leonia Kogan]

Eric Greisen wrote:

> I have found the source of the trouble and I do not know what is the
> right thing to do.
> 
> SNSMO smooths delays separately from rates separately from amp/phase.
> So if phases are 0 coming in they are 0 going out except for
> multi-band delays (see below).
> 
> CLCAL smooths each separately but in the same subroutine.  Then it
> says if the single band delay has changed, the phases should change
> multiplied by FOFF(iif).  That factor seems wrong to me - should it
> not be Fzero + FOFF(iif)?  That aside, should one change phases for a
> smooth of delay?  Note that multi-band delay changes phases in SNSMO:
> 
>                   IF ((IPHASE.NE.FBLANK) .AND. (AMP.NE.FBLANK)) THEN
> C                                       Multiband delay correction
>                                     
>                      IF ((IFEND.GT.IFBEG) .AND. SMOPHS .AND.
>      *                  (RECR(MB1KOL).NE.FBLANK)) THEN
>                         PHASE = PHASE + TWOPI * (FREQS(I)-FREQS(1)) *
>      *                     RECR(MB1KOL)
> 
> but not in CLCAL.  Now I am really confused.
> 
> What do people thing is correct?


I think that the answer depends on definition of the phase change:

1. IF the phase change due to the change of delay by DTAU is the change 
of [PHAS(FZERO+FOFF) - PHAS(FZERO)]  THEN
                DPH1 = FOFF * DTAU

2. IF the phase change due to the change of delay by DTAU is change of
     [PHAS(FZERO+FOFF)] THEN
                DPH2 = (FZERO+FOFF) * DTAU = FZERO*DTAU + DPH1






> 
> Note Craig that the CUBE mode has real difficulty extrapolating so
> sensible phases in the smoothed SN table become crazy in the CL
> table.
> 
> Eric Greisen
> 
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