;+ ; NAME: ; MAKE_TPCAL ; PURPOSE: ; Interim routine to generate the TPCAL segment record from TPCAL data, ; for writing into each scan by ARCHIVE. ; CATEGORY: ; OVRO APC DATA CALIBRATION ; CALLING SEQUENCE: ; make_tpcal,tls,tpcal,tprms,ndavg,refcal ; INPUTS: ; tls A Time/Label structure from the header of the REF-TPCAL scan ; that took the data. ; tpcal An array containing the 27-m total power calibration factors, ; of size (2,2,85), where the first index is the feed (0 = RH ; position, 1 = LH position), the second is the antenna ; (0 = Ant 1, 1 = Ant 2) and the third is the frequencies ; (all harmonics except H89). The calibration factors ; (unnormalized to the noise diode) are in units/SFU. ; tprms An identical array to TPCAL, giving the corresponding RMS ; deviations derived from multiple measurements, in the same ; units as for TPCAL. ; ndavg An identical array to TPCAL, giving the corrsponding noise ; diode increment, in raw units. The final TPCAL factors ; will be scaled by a factor derived from these. ; refcal The REFCAL structure from the data (.ARC) file containing ; the TPCAL observations. This will have the previously ; active TPCAL calibration. ; OPTIONAL (KEYWORD) INPUT PARAMETERS: ; ROUTINES CALLED: ; get_nd_eff, tlsnow, get_tl_struct, tl_encode, dayofyr ; OUTPUTS: ; COMMENTS: ; The values written to the file are in scaled, 2-byte integer form. To convert ; the 2-byte values back to units/SFU, read the integer value, multiply by 0.1, ; and apply to TP data by dividing by the factors. ; SIDE EFFECTS: ; Data are written to the file !DEFAULTS.EPHEMDIR+'TPCAL.REC'. ; RESTRICTIONS: ; Provision is made for 2-m calibration factors, but the actual 2-m ; calibration is not yet set, so this routine just leaves the space ; for these values blank (or uses values from an earlier determination). ; MODIFICATION HISTORY: ; Written 23-Jul-1999 by Dale E. Gary ; 11-Sep-1999 DG ; Changed entire scheme to use 2-byte rather than byte values, so that ; digitization is not a problem for the 2-m dish data. ; 14-Sep-1999 DG ; Had to scale the 27 m TPCALs by 10 rather than 100, to prevent overflow ; of 2-byte word. ; 12-Nov-1999 DG ; Read existing disk file (to preserve 2m information) rather than ; create a new one from scratch. ; 11-Jan-2000 DG ; Eliminated hardwired directory locations. ; 23-Jul-2000 DG ; Changed to use the function TLSNOW (no functional change). ; 03-Sep-2000 DG ; Added REFCAL to argument list. ;- pro make_tpcal,tls,tpcal,tprms,ndavg,oldtp nf = n_elements(tpcal[0,0,*]) ikey = [7,9,14,25,41,53]-5 ; Key harmonics for calculation of ND_eff value nd_eff = fltarr(4) ; Array to hold effective noise diode value (4 feeds) ; Calculate the effective noise diode value relative to 500 for iant = 0,1 do $ for ifeed = 0,1 do $ nd_eff[ifeed+iant*2] = get_nd_eff(ikey,ndavg[ifeed,iant,*]) ; Create an appropriate TIME/LABEL structure containing the current ; system date/time tl_struct = tlsnow(!SEGM.TPCAL) ; Convert tl_struct to binary data tldata = tl_encode(tl_struct) tls27m = tl_encode(tls) ; Reformat the TPCAL records directly from the .ARC file, as contained ; in the REFCAL structure. For older data, where there is no REFCAL ; structure, REFCAL will not be a structure, in which case we create a ; new file. if (n_elements(oldtp) eq 0) then begin ; Declare storage for entire record data = intarr(1024) data2 = intarr(1024) ; Empty 2-m TLS structure, for now, since no 2-m calibration yet tls02m = tl_encode(get_tl_struct()) data[24:35] = tls02m ; Time/Label field of 2-m data epoch endif else begin ; OLDTP exists, so use it, but overwrite 27-m factors with newly ; determined factors (this will preserve 2m info) data = reform(oldtp[*,0]) data2 = reform(oldtp[*,1]) endelse ; Fill in record data[0:11] = tldata ; Time/Label field data[12:23] = tls27m ; Time/Label field of 27-m data epoch ; For the second record, update the NRS field tl_struct.nrs = 2 tldata = tl_encode(tl_struct) data2[0:11] = tldata ; Loop over frequency, scaling the TP and RMS data to the ND_eff value and ; converting to units of 1/10 of a unit/SFU. Replace all bad (-99) data ; with 'FFFF'x for i = 0, 48 do begin bad = where(tpcal[*,*,i] eq -99,nbad) tpdat = uint(reform(tpcal[*,*,i])*10./nd_eff) if (nbad ne 0) then tpdat[bad] = 'FFFF'x bad = where(tprms[*,*,i] eq -99,nbad) tprmsdat = uint(reform(tprms[*,*,i])*10./nd_eff) if (nbad ne 0) then tprmsdat[bad] = 'FFFF'x ; TPDAT now contains the 4 scaled calibration factors for feeds 1I, 1L, 2R, and 2I. ; TPRMSDAT now contains the 4 scaled rms values corresponding to these feeds. ; To get back the actual calibration factors in units/SFU, read the 2-byte data, ; and multiply by 0.1. To apply it, multiply it into the data. wrdoff = 36 + i*20 data[wrdoff] = reform(tpdat,4) data[wrdoff+10] = reform(tprmsdat,4) endfor for i = 49, nf-1 do begin bad = where(tpcal[*,*,i] eq -99,nbad) tpdat = uint(reform(tpcal[*,*,i])*10./nd_eff) if (nbad ne 0) then tpdat[bad] = 'FFFF'x bad = where(tprms[*,*,i] eq -99,nbad) tprmsdat = uint(reform(tprms[*,*,i])*10./nd_eff) if (nbad ne 0) then tprmsdat[bad] = 'FFFF'x ; TPDAT now contains the 4 scaled calibration factors for feeds 1I, 1L, 2R, and 2I. ; TPRMSDAT now contains the 4 scaled rms values corresponding to these feeds. ; To get back the actual calibration factors in units/SFU, read the 2-byte data, ; and multiply by 0.1. To apply it, multiply it into the data. ; This next line is because harmonic 89 is not measured, so have to skip the ; next to last frequency. if (i eq nf-1) then begin j = nf wrdoff = 12 + (i-49)*20 data2[wrdoff] = ['FFFF'x,'FFFF'x,'FFFF'x,'FFFF'x] data2[wrdoff+10] = ['FFFF'x,'FFFF'x,'FFFF'x,'FFFF'x] endif else j = i wrdoff = 12 + (j-49)*20 data2[wrdoff] = reform(tpdat,4) data2[wrdoff+10] = reform(tprmsdat,4) endfor cd,!defaults.ephemdir,current=cwd ; Open the output file to write the record. This will overwrite any ; existing file, or create a new one if none exists. openw,lun,/get_lun,'tpcal.rec',bufsiz=2048 ; Create an associated variable for the file b = assoc(lun,intarr(1024)) ; Write the data b(0) = data b(1) = data2 ; Close the file and free the unit number free_lun,lun cd,cwd return end