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GMVA Setups

Modified 11:37, 30 Mar 2023 by jwagner | Page History
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  1. 1. Standard Mode (4Gbps, DDC, dual-pol)
      1. 1.1.1. VLBA & GBT
      2. 1.1.2. DBBC2 Stations (Eb,On,Ys,Mh)
      3. 1.1.3. DBBC3 Stations (Pv)
      4. 1.1.4. R2DBE Stations (GLT, LMT, Haystack)
      5. 1.1.5. KVN
      6. 1.1.6. ALMA
      7. 1.1.7. NOEMA
  2. 2. Broad band mode [experimental] (16Gbps, dual pol)
      1. 2.1.1. GLT
      2. 2.1.2. LMT
      3. 2.1.3. ALMA
      4. 2.1.4. NOEMA
      5. 2.1.5. MOPRA
      6. 2.1.6. KVN
      7. 2.1.7. Onsala
  3. 3. Polarization
      1. 3.1.1. Yebes
      2. 3.1.2. Pico
      3. 3.1.3. ATCA
      4. 3.1.4. Mopra
      5. 3.1.5. ALMA
  4. 4. Previous standard mode (2Gbps, PFB, dual-pol)
  5. 5. ALMA Mode 4 Gbps (fullband mode)
      1. 5.1.1. DBBC2 setup
      2. 5.1.2. FILA10G setup

Standard Mode (4Gbps, DDC, dual-pol)

Starting from Oct 2019 the GMVA will record at 4Gbps.

86012 - 86524 MHz  (512 MHz, dual-polarization)

For the DiFX Zoom band setup see the Correlator_Cookbook, A1: GMVA_correlation

VLBA & GBT

RDBE DDC mode with 4x128 MHz bands, dual-pol

sky  start [MHz] sky  stop [MHz] bandwidth [MHz] Sideband
86012 86140 128 USB
86140 86268 128 USB
86268 86396 128 USB
86396 86524 128 USB

Freq / Bitstream setup:

 chan_def = : 86012.00 MHz : U : 128.00 MHz : &CH01 : &BBC01 : &NoCal; *Rcp
 chan_def = : 86012.00 MHz : U : 128.00 MHz : &CH02 : &BBC02 : &NoCal; *Lcp
 chan_def = : 86140.00 MHz : U : 128.00 MHz : &CH03 : &BBC03 : &NoCal; *Rcp
 chan_def = : 86140.00 MHz : U : 128.00 MHz : &CH04 : &BBC04 : &NoCal; *Lcp
 chan_def = : 86268.00 MHz : U : 128.00 MHz : &CH05 : &BBC05 : &NoCal; *Rcp
 chan_def = : 86268.00 MHz : U : 128.00 MHz : &CH06 : &BBC06 : &NoCal; *Lcp
 chan_def = : 86396.00 MHz : U : 128.00 MHz : &CH07 : &BBC07 : &NoCal; *Rcp
 chan_def = : 86396.00 MHz : U : 128.00 MHz : &CH08 : &BBC08 : &NoCal; *Lcp

DBBC2 Stations (Eb,On,Ys,Mh)

All DBBC2 stations should use:

  • DDC mode (firmware 107 beta3)
  • LO=85500
  • 2nd Nyquist zone: 512 -1024 MHz
  • Use 2 Core-boards

Bitstream setup:

Note: Use astro if IFs are connected to Boards A+B, use astro2 if IFs are connected to boards A+C

  • On,Ef:     dbbcform=astro
  • Ys,Mh:    dbbcform=astro2

 

bbc freq sideband bandwidth sky start [MHz] sky stop
960 USB 64 86460 86524
LSB 64 86460 86396
832 USB 64 86332 86396
LSB 64 86332 86268
704 USB 64 86204 86268
LSB 64 86204 86140
576 USB 64 86076 86140
LSB 64 86076 86012

DBBC3 Stations (Pv)

All DBBC3 stations:

  • DDC_U mode (firmware V126)

PV setup:

  • 1st LO=92100 (dictated by the DBBC2 IF requirements)
  • 2nd LO= 9048 (DBBC3 GComo)
    • Use E90LI IFs (4-9GHz LSB)
    • Baseband: 0-4 GHz USB => 83052 - 87052 sky freq

Bitstream order (fixed for DDC_U mode):

  • BBC1-USB, BBC1-LSB, BBC2-USB, BBC2-LSB, ...

Observations can be done with 128MHz or 64 MHz subbands (see tables below)

BBC setup  (DDC_U with 64MHz bands):

bbc freq net sideband bandwidth sky start sky stop
3024 LSB 64 86012 86076
USB 64 86076 86140
3152 LSB 64 86140 86204
USB 64 86204 86268
3280 LSB 64 86268 86332
USB 64 86332 86396
3408 LSB 64 86396 86460
USB 64 86460 86524

BBC setup  (DDC_U with 128MHz bands):

bbc freq net sideband bandwidth sky start sky stop
3088.0 LSB 128 86012 86140
USB 128 86140 86268
3344.0 LSB 128 86268 86396
USB 128 86396 86524

Bandpass shapes @64and 128 MHz

64 MHz 128 MHz
DBBC3_64MHz.png DBBC3_128MHz.png

R2DBE Stations (GLT, LMT, Haystack)

  • R2DBE stations must manually setup their systems (no vex/drudg support)
  • IF setup is flexible as long as the 2GHz band includes the 86012 - 86524 MHz sub-band
  • Desired tuning would yield: 85244 - 87292 USB or LSB.

The DiFX v2d antenna definitions would be

DATASTREAM dsGltLCP { filelist=gl-pol1.flist format=VDIF/8224 }
DATASTREAM dsGltRCP { filelist=gl-pol2.flist format=VDIF/8224 }
ANTENNA GL { datastreams=dsGltLCP,dsGltRCP zoom=vlbaZoom }

KVN

  • Bistream order: ?
sideband bandwidth sky start [MHz] sky stop
USB 64 86460 86524
LSB 64 86460 86396
USB 64 86332 86396
LSB 64 86332 86268
USB 64 86204 86268
LSB 64 86204 86140
USB 64 86076 86140
LSB 64 86076 86012

ALMA

ALMA will record a band of 1.875 GHz subdivided into 62.5MHz wide sub-bands:

     chan_def = &W : 87210.453125 MHz : L : 62.5 MHz : &CH01 : &BBC07 : &cp;
     chan_def = &W : 87151.859375 MHz : L : 62.5 MHz : &CH02 : &BBC07 : &cp;
     chan_def = &W : 87093.265625 MHz : L : 62.5 MHz : &CH03 : &BBC07 : &cp;
     chan_def = &W : 87034.671875 MHz : L : 62.5 MHz : &CH04 : &BBC07 : &cp;
     chan_def = &W : 86976.078125 MHz : L : 62.5 MHz : &CH05 : &BBC07 : &cp;
     chan_def = &W : 86917.484375 MHz : L : 62.5 MHz : &CH06 : &BBC07 : &cp;
     chan_def = &W : 86858.890625 MHz : L : 62.5 MHz : &CH07 : &BBC07 : &cp;
     chan_def = &W : 86800.296875 MHz : L : 62.5 MHz : &CH08 : &BBC07 : &cp;
     chan_def = &W : 86741.703125 MHz : L : 62.5 MHz : &CH09 : &BBC07 : &cp;
     chan_def = &W : 86683.109375 MHz : L : 62.5 MHz : &CH10 : &BBC07 : &cp;
     chan_def = &W : 86624.515625 MHz : L : 62.5 MHz : &CH11 : &BBC07 : &cp;
     chan_def = &W : 86565.921875 MHz : L : 62.5 MHz : &CH12 : &BBC07 : &cp;
     chan_def = &W : 86507.328125 MHz : L : 62.5 MHz : &CH13 : &BBC07 : &cp;
     chan_def = &W : 86448.734375 MHz : L : 62.5 MHz : &CH14 : &BBC07 : &cp;
     chan_def = &W : 86390.140625 MHz : L : 62.5 MHz : &CH15 : &BBC07 : &cp;
     chan_def = &W : 86331.546875 MHz : L : 62.5 MHz : &CH16 : &BBC07 : &cp;
     chan_def = &W : 86272.953125 MHz : L : 62.5 MHz : &CH17 : &BBC07 : &cp;
     chan_def = &W : 86214.359375 MHz : L : 62.5 MHz : &CH18 : &BBC07 : &cp;
     chan_def = &W : 86155.765625 MHz : L : 62.5 MHz : &CH19 : &BBC07 : &cp;
     chan_def = &W : 86097.171875 MHz : L : 62.5 MHz : &CH20 : &BBC07 : &cp;
     chan_def = &W : 86038.578125 MHz : L : 62.5 MHz : &CH21 : &BBC07 : &cp;
     chan_def = &W : 85979.984375 MHz : L : 62.5 MHz : &CH22 : &BBC07 : &cp;
     chan_def = &W : 85921.390625 MHz : L : 62.5 MHz : &CH23 : &BBC07 : &cp;
     chan_def = &W : 85862.796875 MHz : L : 62.5 MHz : &CH24 : &BBC07 : &cp;
     chan_def = &W : 85804.203125 MHz : L : 62.5 MHz : &CH25 : &BBC07 : &cp;
     chan_def = &W : 85745.609375 MHz : L : 62.5 MHz : &CH26 : &BBC07 : &cp;
     chan_def = &W : 85687.015625 MHz : L : 62.5 MHz : &CH27 : &BBC07 : &cp;
     chan_def = &W : 85628.421875 MHz : L : 62.5 MHz : &CH28 : &BBC07 : &cp;
     chan_def = &W : 85569.828125 MHz : L : 62.5 MHz : &CH29 : &BBC07 : &cp;
     chan_def = &W : 85511.234375 MHz : L : 62.5 MHz : &CH30 : &BBC07 : &cp;
     chan_def = &W : 85452.640625 MHz : L : 62.5 MHz : &CH31 : &BBC07 : &cp;
     chan_def = &W : 85394.046875 MHz : L : 62.5 MHz : &CH32 : &BBC07 : &cp;

     chan_def = &W : 87210.453125 MHz : L : 62.5 MHz : &CH33 : &BBC08 : &cp;
     chan_def = &W : 87151.859375 MHz : L : 62.5 MHz : &CH34 : &BBC08 : &cp;
     chan_def = &W : 87093.265625 MHz : L : 62.5 MHz : &CH35 : &BBC08 : &cp;
     chan_def = &W : 87034.671875 MHz : L : 62.5 MHz : &CH36 : &BBC08 : &cp;
     chan_def = &W : 86976.078125 MHz : L : 62.5 MHz : &CH37 : &BBC08 : &cp;
     chan_def = &W : 86917.484375 MHz : L : 62.5 MHz : &CH38 : &BBC08 : &cp;
     chan_def = &W : 86858.890625 MHz : L : 62.5 MHz : &CH39 : &BBC08 : &cp;
     chan_def = &W : 86800.296875 MHz : L : 62.5 MHz : &CH40 : &BBC08 : &cp;
     chan_def = &W : 86741.703125 MHz : L : 62.5 MHz : &CH41 : &BBC08 : &cp;
     chan_def = &W : 86683.109375 MHz : L : 62.5 MHz : &CH42 : &BBC08 : &cp;
     chan_def = &W : 86624.515625 MHz : L : 62.5 MHz : &CH43 : &BBC08 : &cp;
     chan_def = &W : 86565.921875 MHz : L : 62.5 MHz : &CH44 : &BBC08 : &cp;
     chan_def = &W : 86507.328125 MHz : L : 62.5 MHz : &CH45 : &BBC08 : &cp;
     chan_def = &W : 86448.734375 MHz : L : 62.5 MHz : &CH46 : &BBC08 : &cp;
     chan_def = &W : 86390.140625 MHz : L : 62.5 MHz : &CH47 : &BBC08 : &cp;
     chan_def = &W : 86331.546875 MHz : L : 62.5 MHz : &CH48 : &BBC08 : &cp;
     chan_def = &W : 86272.953125 MHz : L : 62.5 MHz : &CH49 : &BBC08 : &cp;
     chan_def = &W : 86214.359375 MHz : L : 62.5 MHz : &CH50 : &BBC08 : &cp;
     chan_def = &W : 86155.765625 MHz : L : 62.5 MHz : &CH51 : &BBC08 : &cp;
     chan_def = &W : 86097.171875 MHz : L : 62.5 MHz : &CH52 : &BBC08 : &cp;
     chan_def = &W : 86038.578125 MHz : L : 62.5 MHz : &CH53 : &BBC08 : &cp;
     chan_def = &W : 85979.984375 MHz : L : 62.5 MHz : &CH54 : &BBC08 : &cp;
     chan_def = &W : 85921.390625 MHz : L : 62.5 MHz : &CH55 : &BBC08 : &cp;
     chan_def = &W : 85862.796875 MHz : L : 62.5 MHz : &CH56 : &BBC08 : &cp;
     chan_def = &W : 85804.203125 MHz : L : 62.5 MHz : &CH57 : &BBC08 : &cp;
     chan_def = &W : 85745.609375 MHz : L : 62.5 MHz : &CH58 : &BBC08 : &cp;
     chan_def = &W : 85687.015625 MHz : L : 62.5 MHz : &CH59 : &BBC08 : &cp;
     chan_def = &W : 85628.421875 MHz : L : 62.5 MHz : &CH60 : &BBC08 : &cp;
     chan_def = &W : 85569.828125 MHz : L : 62.5 MHz : &CH61 : &BBC08 : &cp;
     chan_def = &W : 85511.234375 MHz : L : 62.5 MHz : &CH62 : &BBC08 : &cp;
     chan_def = &W : 85452.640625 MHz : L : 62.5 MHz : &CH63 : &BBC08 : &cp;
     chan_def = &W : 85394.046875 MHz : L : 62.5 MHz : &CH64 : &BBC08 : &cp;

NOEMA

The NOEMA frequency setup for 4 Gbps x 2-pol is as in their 2022 frequency spreadsheet, screenshot below.

The default freq block for 4 Gbps is

def 86012.00MHz32x64MHz;
* stations=Nn
* noema-vex-defs.py -r 5 -f 92.764
   sample_rate = 128.0 Ms/sec;  * (2bits/sample)
   * Recorder 5, slot 1, LSB-Inner, LCP, subbands 16-31
   chan_def = &B: 86012.00 MHz : U : 64.00 MHz : &CH01 : &BBC01 : &NoCal;
   chan_def = &B: 86076.00 MHz : U : 64.00 MHz : &CH02 : &BBC01 : &NoCal;
   chan_def = &B: 86140.00 MHz : U : 64.00 MHz : &CH03 : &BBC01 : &NoCal;
   chan_def = &B: 86204.00 MHz : U : 64.00 MHz : &CH04 : &BBC01 : &NoCal;
   chan_def = &B: 86268.00 MHz : U : 64.00 MHz : &CH05 : &BBC01 : &NoCal;
   chan_def = &B: 86332.00 MHz : U : 64.00 MHz : &CH06 : &BBC01 : &NoCal;
   chan_def = &B: 86396.00 MHz : U : 64.00 MHz : &CH07 : &BBC01 : &NoCal;
   chan_def = &B: 86460.00 MHz : U : 64.00 MHz : &CH08 : &BBC01 : &NoCal;
   chan_def = &B: 86524.00 MHz : U : 64.00 MHz : &CH09 : &BBC01 : &NoCal;
   chan_def = &B: 86588.00 MHz : U : 64.00 MHz : &CH10 : &BBC01 : &NoCal;
   chan_def = &B: 86652.00 MHz : U : 64.00 MHz : &CH11 : &BBC01 : &NoCal;
   chan_def = &B: 86716.00 MHz : U : 64.00 MHz : &CH12 : &BBC01 : &NoCal;
   chan_def = &B: 86780.00 MHz : U : 64.00 MHz : &CH13 : &BBC01 : &NoCal;
   chan_def = &B: 86844.00 MHz : U : 64.00 MHz : &CH14 : &BBC01 : &NoCal;
   chan_def = &B: 86908.00 MHz : U : 64.00 MHz : &CH15 : &BBC01 : &NoCal;
   chan_def = &B: 86972.00 MHz : U : 64.00 MHz : &CH16 : &BBC01 : &NoCal;
   * Recorder 5, slot 2, LSB-Inner, RCP, subbands 16-31
   chan_def = &B: 86012.00 MHz : U : 64.00 MHz : &CH17 : &BBC02 : &NoCal;
   chan_def = &B: 86076.00 MHz : U : 64.00 MHz : &CH18 : &BBC02 : &NoCal;
   chan_def = &B: 86140.00 MHz : U : 64.00 MHz : &CH19 : &BBC02 : &NoCal;
   chan_def = &B: 86204.00 MHz : U : 64.00 MHz : &CH20 : &BBC02 : &NoCal;
   chan_def = &B: 86268.00 MHz : U : 64.00 MHz : &CH21 : &BBC02 : &NoCal;
   chan_def = &B: 86332.00 MHz : U : 64.00 MHz : &CH22 : &BBC02 : &NoCal;
   chan_def = &B: 86396.00 MHz : U : 64.00 MHz : &CH23 : &BBC02 : &NoCal;
   chan_def = &B: 86460.00 MHz : U : 64.00 MHz : &CH24 : &BBC02 : &NoCal;
   chan_def = &B: 86524.00 MHz : U : 64.00 MHz : &CH25 : &BBC02 : &NoCal;
   chan_def = &B: 86588.00 MHz : U : 64.00 MHz : &CH26 : &BBC02 : &NoCal;
   chan_def = &B: 86652.00 MHz : U : 64.00 MHz : &CH27 : &BBC02 : &NoCal;
   chan_def = &B: 86716.00 MHz : U : 64.00 MHz : &CH28 : &BBC02 : &NoCal;
   chan_def = &B: 86780.00 MHz : U : 64.00 MHz : &CH29 : &BBC02 : &NoCal;
   chan_def = &B: 86844.00 MHz : U : 64.00 MHz : &CH30 : &BBC02 : &NoCal;
   chan_def = &B: 86908.00 MHz : U : 64.00 MHz : &CH31 : &BBC02 : &NoCal;
   chan_def = &B: 86972.00 MHz : U : 64.00 MHz : &CH32 : &BBC02 : &NoCal;
enddef;

Broad band mode [experimental] (16Gbps, dual pol)

Desired tuning would yield: 85244 - 87292 USB or LSB.

GLT

LMT

ALMA

NOEMA

MOPRA

KVN

Onsala

Polarization

Yebes

Circular. Mount info for the 86 GHz receiver is Nasmyth Right since 2018.1, previously Nasmyth Left. Can specify it in VEX under DiFX 2.6.2+ via

def YEBES40M;
     axis_type = nasmyth : r;
     antenna_motion = el :  60.0 deg/min : 20 sec;  * 1000.000 deg/sec/sec
     antenna_motion = az :  60.0 deg/min : 20 sec;  * 1000.000 deg/sec/sec
     axis_offset =    1.99600 m;
enddef;

Pico

Circular. Nasmyth Left probably, as hardoded in (and any VEX overridden by) difxio antenna_db.c, but can try VEX,

def PICOVEL;
     axis_type = nasmyth : l;
     antenna_motion = el :  30.0 deg/min : 20 sec;  * 1000.000 deg/sec/sec
     antenna_motion = az :  30.0 deg/min : 20 sec;  * 1000.000 deg/sec/sec
     axis_offset =    0.00000 m;
enddef;

ATCA

Observes in linear polarization, but data get converted on-site into a circular basis. The LBA-formatted data are thus circular. Unknown ellipticity, but probably low.

Mopra

Linear polarized 86 GHz receiver. Mount is Az-El. Data must be rotated after correlation. No calibration data for PolConvert.

Unfortunately, code plus observational issues for Mopra with a CASA PolSolve --> PolConvert approach.

Instead, Ivan M Vidal has a QWP_ROTATE.py module and QWP_APPLY_...py script. Rotation by a constant factor, not much calibration.

From GMVA C221 it appeas that the correct settinigs are 45 deg in a +1 sense cf. QWP_APPLY_... code.

ALMA

Linear polarized. ALMA QA2 team provides ready calibration tables to use in PolConvert.

Previous standard mode (2Gbps, PFB, dual-pol)

This mode is deprecated. New standard mode mode is DDC @ 4Gbps (see above)

The standard GMVA frequency setup is used for more than 90% of all observations. The data-rate is at present restricted to 2 Gbps due to limitations at the VLBA, which may get lifted in the near future.

DBBC-PFB-Bands.png

Other frequency setups which are listed in the VLBA table of setups (see frequency.dat of SCHED) for the 86 GHz receiver are possible though, but not all stations may be able to tune to all the LOs given in that table.

Setup (European stations & VLBA)

def 86380.00MHz16x32MHz;
* mode =  1    stations =Eb:Ef:On:Mh:Ys:Pv:Gb:Nl:Pt:La:Fd:Kp:Ov:Br:Mk:Lm
     sample_rate =  64.000 Ms/sec;  * (2bits/sample)
     chan_def = : 86380.00 MHz : L :  32.00 MHz : &CH01 : &BBC01 : &L_Cal; *Rcp
     chan_def = : 86380.00 MHz : L :  32.00 MHz : &CH02 : &BBC02 : &L_Cal; *Lcp
     chan_def = : 86348.00 MHz : L :  32.00 MHz : &CH03 : &BBC03 : &L_Cal; *Rcp
     chan_def = : 86348.00 MHz : L :  32.00 MHz : &CH04 : &BBC04 : &L_Cal; *Lcp
     chan_def = : 86316.00 MHz : L :  32.00 MHz : &CH05 : &BBC05 : &L_Cal; *Rcp
     chan_def = : 86316.00 MHz : L :  32.00 MHz : &CH06 : &BBC06 : &L_Cal; *Lcp
     chan_def = : 86284.00 MHz : L :  32.00 MHz : &CH07 : &BBC07 : &L_Cal; *Rcp
     chan_def = : 86284.00 MHz : L :  32.00 MHz : &CH08 : &BBC08 : &L_Cal; *Lcp
     chan_def = : 86252.00 MHz : L :  32.00 MHz : &CH09 : &BBC09 : &L_Cal; *Rcp
     chan_def = : 86252.00 MHz : L :  32.00 MHz : &CH10 : &BBC10 : &L_Cal; *Lcp
     chan_def = : 86220.00 MHz : L :  32.00 MHz : &CH11 : &BBC11 : &L_Cal; *Rcp
     chan_def = : 86220.00 MHz : L :  32.00 MHz : &CH12 : &BBC12 : &L_Cal; *Lcp
     chan_def = : 86188.00 MHz : L :  32.00 MHz : &CH13 : &BBC13 : &L_Cal; *Rcp
     chan_def = : 86188.00 MHz : L :  32.00 MHz : &CH14 : &BBC14 : &L_Cal; *Lcp
     chan_def = : 86156.00 MHz : L :  32.00 MHz : &CH15 : &BBC15 : &L_Cal; *Rcp
     chan_def = : 86156.00 MHz : L :  32.00 MHz : &CH16 : &BBC16 : &L_Cal; *Lcp
enddef;

Setup (KVN stations)

def 86156.00MHz8x32MHz;
* mode =  1    stations =Ky:Ku:Kt
     sample_rate =  64.000 Ms/sec;  * (2bits/sample)
     chan_def = : 86156.00 MHz : L :  32.00 MHz : &CH01 : &BBC01 : &NoCal; *Lcp
     chan_def = : 86156.00 MHz : L :  32.00 MHz : &CH02 : &BBC02 : &NoCal; *Rcp
     chan_def = : 86156.00 MHz : U :  32.00 MHz : &CH03 : &BBC01 : &NoCal; *Lcp
     chan_def = : 86156.00 MHz : U :  32.00 MHz : &CH04 : &BBC02 : &NoCal; *Rcp
     chan_def = : 86220.00 MHz : L :  32.00 MHz : &CH05 : &BBC01 : &NoCal; *Lcp
     chan_def = : 86220.00 MHz : L :  32.00 MHz : &CH06 : &BBC02 : &NoCal; *Rcp
     chan_def = : 86220.00 MHz : U :  32.00 MHz : &CH07 : &BBC01 : &NoCal; *Lcp
     chan_def = : 86220.00 MHz : U :  32.00 MHz : &CH08 : &BBC02 : &NoCal; *Rcp
enddef;

LO=85500 MHz

DBBC2 stations have to use the flex mode with the following channel selection in the prc-file:

vsi1=a05,a06,a07,a08,a09,a10,a11,a12,b05,b06,b07,b08,b09,b10,b11,b12

Stations which can only offer a reduced bandwidth of bitrate are considered non-standard. Setups have to be negotiated with the GMVA technical team (chair: W. Alef, MPIfR)

All other setups are non-standard and require consultation with the GMVA scheduler or technical team (chair: W. Alef, MPIfR).

ALMA Mode 4 Gbps (fullband mode)

Deprecated mode. Do not use!

The description is kept for reference only.

For ALMA compatibilty the DBBC2 stations must observe in fullband PFB mode covering the full 512 MHz per polarisation in a single IF channel. 

NOTE: You must use the last two core boards in the DBBC2 board stack for the fullband mode. All data from the last Core2Board (presumably IFD) will be send to VSI1 and all from last-1 (presumably IFC) to VSI2. There is no option to choose something else.

DBBC2 setup

Restart of the DBBC PFB control software is not required unless the DDC mode was used prior to the fullband mode.

The only option to be commanded is

dbbcform=full_auto

FILA10G setup

To combine the both VSI streams it is usually enough to set the Fila10G to:

splitmode off
inputselect vsi1-2
vsi_samplerate 64000000
reset keepsync
vdif_station PV        (<-change to your station code) 
vdif_frame 2 2 5000 ct=off
reset keepsync
regwrite chan_perm 0 0x21200100
regwrite chan_perm 1 0x23220302
regwrite chan_perm 2 0x25240504
regwrite chan_perm 3 0x27260706
regwrite chan_perm 4 0x29280908
regwrite chan_perm 5 0x2B2A0B0A
regwrite chan_perm 6 0x2D2C0D0C
regwrite chan_perm 7 0x2F2E0F0E
regwrite chan_perm 8 0x31301110
regwrite chan_perm 9 0x33321312
regwrite chan_perm 10 0x35341514
regwrite chan_perm 11 0x37361716
regwrite chan_perm 12 0x39381918
regwrite chan_perm 13 0x3B3A1B1A
regwrite chan_perm 14 0x3D3C1D1C
regwrite chan_perm 15 0x3F3E1F1E
reset keepsync
timesync

Note: the last command "timesync" will only work if your FiLA10G is equipped with a GPS module/antenna. If this is not the case at your station you can do the time syncronization either:

  • manually:  timesync  <YYYY>-<MM>-<DD>T<hh>:<mm>:<ss>

  • use the FS fmset command. This must be done prior to executing the above procedure!

IMPORTANT: Do not use FMSET to sync the FILA10G after executing the above procedure as this will partially overwrite the above setting.

 

Note: The regwrite statements will join the two steams to a single 64 bit stream one after each other VSI1 bit 0-31 and VSI2 bit 32 to 61. The correlator expects to have alternating bits from channel 1 and 2. VSI1 bit 0+1, VSI2 bit2+3, ....

The mode has been succesfully tested at Effelsberg (details).