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Backends for EMIR, HERA
Distribution of intermediate frequencies (IFs) to the backends (Status: July 2011)
1. IF distribution in preparation for end of July 2011
2. Old IF distribution (Status: June 2011)

Backends for EMIR, HERA

Backend	Type	Channel Width	Bandwidth	Receiver (width mode)	Status	Remark
4 MHz	Filterbanks	4 MHz	8 or 9 x 1GHz	EMIR, either HERA1 or HERA2 (wide)		(1)
WILMA	Autocorrelator	2 MHz	16 or 18 x 930 MHz	EMIR, HERA (wide)		(2)
FTS	FFTS	195 kHz	8x4 GHz	EMIR, HERA		(3.1)
FTS	FFTS	50 kHz		EMIR, HERA (narrow)		(3.2)
VESPA	Autocorrelator	3.3 kHz-1.25 MHz	10-512 MHz	EMIR, HERA (narrow)		(4)
XPOL	VESPA	40kHz-1.25MHz	120-640MHz	EMIR		(5)
nbc / continuum	continuum	1 GHz				(6)
bbc	continuum	8 GHz				(7)

See here, for the present status of the backends. For more information on the capabilities of EMIR, see here. In general, several backends can be attached to one receiver. Exceptions are listed below. The pako manual describes in detail how to configure the backends.

The new backends are online! No more ! <CK 2-Aug-2011>

4MHz Filterbank: max. 9 parts; use of the 4MHz filterbank excludes the use of VESPA on the same receiver. Frequency switching not available. While the channel spacing is 4MHz, the 3dB width is 5.4MHz and the noise equivalent width is 6.5 MHz
WILMA: The Wideband Line Multiple Autocorrelator for EMIR and HERA
Fast Fourier Transform Spectrometer (FTS): In July 2011, the FTS and the FTS were upgraded to 32GHz bandwidth with 195 resolution for EMIR and HERA. They are available to all observers since 2-Aug-2011. See the document of Gilles Butin on the Spectrum Slicers for FFT Spectrometers and see the backend status page. In the winter semester 2010/11 we offer 8 units covering 2x4GHz of bandwidth with a fixed resolution of 195kHz for EMIR.
VESPA: The Versatile SPectrometer Array. Up to 18000 channels. In connection with HERA (9 pixels) the following combinations of resolution (kHz) and bandwidth (MHz) are possible: (20/40), (40,80), (80, 160), (320,320), (1250, 640); VESPA User Guide (2002), Summary in IRAM Newsletter No. 54 (Dec 2002), local contact: G. Paubert
XPOL: Line and continuum polarimetry is possible at the 30m using a new type of IF polarimeter designated XPOL. The central feature of XPOL is the correlator VESPA where the IF signals from two orthogonally polarized receivers are cross correlated to determine the four Stokes parameters. A manual is in preparation, contact: C. Thum
Continuum backend with 1GHz width, is still the old system used for the ABCD receivers
Continuum backend with 8GHz width, fully exploiting the increased bandwidth of EMIR, is available since 2-Aug-2011. bbc cannot be connected to HERA.

Decommissioned backends:

MAMBO2 has been decommissioned mid 2011. ABBA1 and ABBA2 (Adc Bolometer Backend) were the bolometer backends for the MAMBO 1mm camera, i.e. dedicated PCs connected to the bolometers.
The 1MHz filterbank has been decommissioned in 4/2008: max. 4 parts; series, parallel, or mixed mode possible; using the 1MHz filterbank with 1GHz bandwidth excludes the use of VESPA with the same receiver. The filterbank can be shifted in multiples of 32MHz from the center frequency of the connected receiver.

Distribution of intermediate frequencies (IFs) to the backends (Status: July 2011)

IF distribution in preparation for end of July 2011

Figure 2: Planned IF distribution for 2011

Old IF distribution (Status: June 2011)

Figure 1: IF distribution (16-Dec-2010 SS/CK)

-  ⇤ ← Revision 56 as of 2011-07-27 17:38:09 → 
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+   ← Revision 61 as of 2011-08-02 13:33:20 → ⇥
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-|| || Type || Channel Width || Bandwidth || Receiver (width mode) || [[http://www.iram.es/IRAMES/mainWiki/TelescopeSystemStatus#BackendStatus|Status]] || Remark ||
+|| Backend || Type || Channel Width || Bandwidth || Receiver (width mode) || [[http://www.iram.es/IRAMES/mainWiki/TelescopeSystemStatus#BackendStatus|Status]] || Remark ||
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-|| '''FTS'''   || FFTS || 195 kHz || 8x4 GHz || EMIR, HERA || {{attachment:kreuz.gif}} || (3.1) ||
|| '''FTS'''   || FFTS || 50 kHz || || EMIR, HERA (narrow) || {{attachment:kreuz.gif}} || (3.2) ||
+|| '''FTS'''   || FFTS || 195 kHz || 8x4 GHz || EMIR, HERA || {{attachment:haken.gif}} || (3.1) ||
|| '''FTS'''   || FFTS || 50 kHz || || EMIR, HERA (narrow) || {{attachment:haken.gif}} || (3.2) ||
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-|| '''bbc''' || continuum || 8 GHz || || || {{attachment:kreuz.gif}} || (7) ||
+|| '''bbc''' || continuum || 8 GHz || || || {{attachment:haken.gif}} || (7) ||
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+The new backends are online! No more {{attachment:kreuz.gif}}! <CK 2-Aug-2011>
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+Line 28:
-. '''Fast Fourier Transform Spectrometer (FTS)''': for the winter semester 2010/11 we offer 8 units covering 2x4GHz of bandwidth with a fixed resolution of 195kHz for EMIR. During July 2011, the FTS and the FTS are upgraded to 32GHz bandwidth with 195 resolution for EMIR and HERA. During this time, none of the FTS units will be available for observations. See the [[http://www.iram.es/IRAMES/mainWiki/TelescopeSystemStatus#BackendStatus|backend status page]].
+. '''Fast Fourier Transform Spectrometer (FTS)''': In July 2011, the FTS and the FTS were upgraded to 32GHz bandwidth with 195 resolution for EMIR and HERA. They are available to all observers since 2-Aug-2011. See the document of Gilles Butin on the [[attachment:butin-32ghz-fts-4jul2011.pdf|Spectrum Slicers for FFT Spectrometers]] and see the [[http://www.iram.es/IRAMES/mainWiki/TelescopeSystemStatus#BackendStatus|backend status page]]. In the winter semester 2010/11 we offer 8 units covering 2x4GHz of bandwidth with a fixed resolution of 195kHz for EMIR.
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+Line 36:
-. '''Continuum backend''' with 8GHz width, fully exploiting the increased bandwidth of EMIR, is in preparation.
+. '''Continuum backend''' with 8GHz width, fully exploiting the increased bandwidth of EMIR, is available since 2-Aug-2011. bbc cannot be connected to HERA.