fx_cor

DESCRIPTION

"fx_cor" is an FX-type software correlator and carries out cross correlation processing using an apriori file. Correlated data are output to a file with a "cout" format. Auto-correlation or cross correlation with zero apriori value are also available.

SYNOPSIS

[Type 1]

fx_cor afile [options]

afile a-priori file name created by "apri_calc"
OPTIONS
--version show program version
--help show how to execute
-integ integration_time set integration period (sec). Default is a scheduled scan period.
-coffset clock_offset set clock offset (sec) applied for fringe search purpose. Positive value menas Y clock tic earlier than X clock tic. Default is 0.0
-crate clock_rate set clock rate (s/s) difference between X and Y station clock applied for fringe search purpose. Default is 0.0
-soffset start_offset set start time offset (integer sec). Default is 0.
-t1pp t1pp set unit integration period (parameter period) (sec) for correlation processing. Default is BT1PP in "cor_head.h" (usually 1)
-pp_nosync turns off the synchronization mode of PP (parameter period) (default is that PP synchronize to second tic)
-lag lagsize set the size of delay lag window. lagsize can be 16, 32, 64, 128, 256, 512, .. Default is DELAYSIZE in cor_head.h
-pmode pmode set plot device mode.
0 : XWINDOW (env PGDISP can change PGPLOT display device) and PostScript file (pgplot.ps or gnuplot.ps) out (dfault)
1 : PostScript file (pgplot.ps or gnuplot.ps) out only
2 : XWINDOW only
-1 : no graphic output
-comment "any_comment"
set comment appeared in a correlation function plot when pmode=0,1,2
-nopcal suppress PCAL (phase calibration) signal detection
-ch1 ch1Y define Y channel for X CH# 1 (default 1).
-ch2 ch2Y define Y channel for X CH# 2 (default 2).
-ch3 ch3Y define Y channel for X CH# 3 (default 3).
-ch4 ch4Y define Y channel for X CH# 4 (default 4).
Note: in case of "cor new" and "fx_cor new", options upto "-ch16 ch16Y" are possible
-orule naming_rule set naming rule of output file name
0 : use program default (cout.txt)
1 : coutNNNNtxt (deflt) where NNNN is 4 digit serial number
2 : coutEXP_CODE/coutYYDDDNNNNXYG.txt
      where   EXP_CODE -- experiment code

                  YY   -- 2 digit year

                  DDD  -- 3 digit day of year

                  NNNN -- 4 digit scan number

                  XY   -- baseline id (2 char or 4 char)

                  G    -- Frequency group (a|b|c|d)
3 : coutYYDDDNNNNXYG.txt
      where   YY   -- 2 digit year

              DDD  -- 3 digit day of year

              NNNN -- 4 digit scan number

              XY   -- baseline id (2 char or 4 char)

              G    -- Frequency group (a|b|c|d)
(default is COUT_NAMING_RULE in cor_head.h)
-odir outdir set output file directory. System default is environmental variable K5COUT. If K5COUT is not defined, program default defined by COUTDFLT in "cor_head.h" is used (usually "../cout").
-rfoffset rf_offset set RF frequency difference between Y and X (RFy-RFx)(Hz)
-cout cout_file set output file name compulsory. If this parameter is set, naming rule and out directory are ignored.
-frstep frstep set fringe phase calculation step in samples
0: automatic calculation
1: every 1 sample
8: every 8 samples
N: every N samples. (Note: N can be any number, but 1000/N must be integer)
default is FRSTEP_FX_COR (in cor_head.h)
-frauto set frstep=0 (automatic calculation mode)
-fall pcalf set PCAL frequency of all channels compulsory (kHz)
-f1 pcalf1 set CH1 PCAL frequency compulsory(kHz)
-f2 pcalf2 set CH2 PCAL frequency compulsory(kHz)(kHz)
-f3 pcalf3 set CH3 PCAL frequency compulsory(kHz)(kHz)
-f4 pcalf4 set CH4 PCAL frequency compulsory(kHz)(kHz)
Note: in case of "cor new" and "fx_cor new", options upto "-f16 pcalf16" are possible
=== options below are dedicated to fx cor and fx cor new ===
-modefr modefr set fringe stopping approximation mode
0: no approximation (exact calculation)
9: 9 level approximation (default)
2: 2 level approximation
3: 3 level approximation
-hanning use Hanning lag window
-hamming use Hamming lag window
-bpf flow:fhigh[:fact][,flow:fhigh[:fact][,flow:fhigh[:fact][,.....]]]
set BPF lower and higher frequencies
flow -- BPF lower cut off frequency in a video band (MHz)
fhigh -- BPF higher cut off frequency in a video band (MHz)
fact -- factor (0.0-1.0), default is 1.0
-bpf2 fc:bw[:fact][,fc:[bw][:fact][,fc:[bw]:fact][,.....]]]
set BPF parameters
fc -- BPF center frequency in a video band (MHz)
bw --- pass band width (MHz)
fact -- factor (0.0-1.0), default is 1.0
-fres fres set frequency resolution (MHz) (deflt 0.0 means AUTO)
-delpcal ch#:fs[:fi][,ch#:fs[:fi][,....]]]}
set PCAL signal frequencies to reject by channel
  ch# -- channel number (starting from 1)
  fs -- lowest frequency of PCAL signals in baseband (MHz)
  fi -- interval of PCAL signals (MHz)
frequencies of PCAL signals removed are fs, fs+fi, fs+2fi, fs+3fi, ...
when fi is omitted, only fs is removed
bandwidth of rejection filter is double the resolution of FFT. this can be changed by option `-pcalbw' below
  or
-delpcal delpcal_file set file name which describes PCAL signal rejection information
-pcalbw bwmhz set bandwidth of PCAL rejection filter (MHz)
default bandwidth is double the resolution of FFT
=== options below are for Ver.2020-05-27 and after ===
-pulsar period:duty:phase_ch1[,phase_ch2[ .... ]]
set Plusar gate parameters at X station
  period -- pulsar period (sec)
  duty -- duty ratio (0.0-1.0)
  phase_ch1 -- phase of pulsar gate at reference time for ch1(deg)
  phase_ch2 -- for ch2
     if phase is omitted, set by ch1's phase
-prt_pulsar HH:MM:SS set reference time for pulsar gate (default is PRT of apriori values)

Contents of file set by the option -delpcal delpcal_file is as follows 

        *** PCAL signal rejection filter file  ***
        **    for option '-delpcal' of fx_cor_new
        **
        **    usage   -delpcal DELPCAL.txt
        **
        **  Format Ver. 2019-08-27
        **
        **    ch#  sFreq(MHz) intFreq(MHz)
        **      where
        **        ch#  :  channel # (starting from 1)
        **                0 means for all channel
        **        sFreq  :  lowest PCAL frequency in channel (MHz)
        **        intFreq  :  interval of PCAL signal (MHz)
        **       Note-- rejected PCAL frequency is sFreq, sFreq+intFreq, sFreq+2*intFreq, ....
        **    [example]
        **      ch#  sFreq(MHz)   intFreq (MHz)  
        **       0     0.01          5.0
        **      set for all channel same parameter
        **
        **      or
        **      1      1.4           5.0
        **      2      8.4           5.0
        **      3      2.4           5.0
        **      4      4.4           5.0
        **      set different start frequency for every channel
        **
        **
        *  CH#  sFreq(MHz)  intFreq(MHz)   
            1     0.4          5.0
            2     3.4          5.0
            3     4.4          5.0
            4     0.4          5.0
            5     4.4          5.0
            6     1.4          5.0
            7     4.4          5.0
            8     2.4          5.0
        *

===== t1pp allowed for less than 1 sec is as follows ====
(this is due to the algorythm)

t1pp
fsampl 0.010.020.040.05 0.1 0.2 0.5
40kHz X OK OK X OK OK OK
100kHz X X OK X X OK X
200kHz X OK OK X OK OK OK
500kHz X X OK X X OK X
1MHz X OK OK X OK OK OK
2MHz OK OK OK OK OK OK OK
4MHz OK OK OK OK OK OK OK
8MHz OK OK OK OK OK OK OK
16MHz OK OK OK OK OK OK OK
32MHz OK OK OK OK OK OK OK

[Type 2]

fx_cor afile [sekibun [soffset [coffset [crate [t1pp [smode [pp_mode [lag_size [tzoom [pmode [comment]]]]]]]]]]]

afile a-priori file name created by "apri_calc"
sekibun integration period (sec). Default is a scheduled scan period.
soffset start time offset (integer sec). Default is 0.
coffset clock offset (sec)
crate clock rate offset (s/s)
t1pp unit integration period (parameter period) (sec)
smode search mode 0: Wide 1: Mid 2:Narrow (default 2) (no more use)
pp_mode PP synchronization mode
0: synchronized to second tic (default)
1: not synchronized to second tic
lag_size lag window size. 16,32,64,128,256,512,.. 0 means lag_size set to DELAYSIZE in "cor_head.h"
tzoom time axis zoom ratio in graphics (int)
0 : full scale (default) as same as 1
-VE : Max position is automatically centered
pmode plot device selection
0: XWINDOW (env PGDISP can change PGPLOT display device) and PostScript file (pgplot.ps or gnuplot.ps) out (default)
1: PostScript file (pgplot.ps or gnuplot.ps) out only
2: XWINDOW only
-1: No graphic output
comment comment appeared in a correlation function plot

[Auto Correlation Mode]

fx_cor k5file1 [k5file2] [options]

k5file1 data file name (K5/VSSP format)
k5file2 2nd data file name for Y station. If directory is omitted in k5file2, directory is considered to be the same as k5file1. If 2nd data file name is omitted, k5file1 is used for both X and Y data file Note: Apriori values are all set to zero. Frequencies are all set to zero.

[Monitoring Environmental Variables]

fx_cor env

check environmental variables used in "fx_cor"

K5APRIDIR -- default directory for apriori file
K5COUT -- default directory for correlation data out
PGDISP -- PGPLOT display device name when plot

Updated on May 28, 2020