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information_for_astronomers:user_guide:signalpathsetup
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information_for_astronomers:user_guide:signalpathsetup [2014/11/20 23:26] bwinkel [Signal paths to the spectroscopic, VLBI, and pulsar backends] |
information_for_astronomers:user_guide:signalpathsetup [2017/01/25 20:24] (current) akraus |
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| ===== Signal paths to the spectroscopic, VLBI, and pulsar backends ===== | ===== Signal paths to the spectroscopic, VLBI, and pulsar backends ===== | ||
| - | There are several IF chains going to the Faraday room (where the backends live), most importantly the VLBA and narrow-band (SB) IF. Furthermore, the 21-cm 7-feed system has its own IF; and some receivers provide a 2+ GHz IF over optical fibers. All IFs are usually used with different bandwidth setups and need different attenuation to bring the power to a level which is appropriate for the backend ADCs. This is done using the so-called **MultiFiBa**. | + | There are several IF chains going to the Faraday room (where the backends live), most importantly the VLBA and narrow-band (SB) IF. Furthermore, the 21-cm 7-feed system has its own IF; and some receivers provide a 2+ GHz IF over optical fibers. All IFs are usually used with different bandwidth setups and need different attenuation to bring the power to a level which is appropriate for the backend ADCs. This is done using the so-called **MultiFiBa**. |
| The various IFs coming from the receivers are fed into the 16-channel MultiFiBa, which allows to apply several internal bandpass filters and attenuation. Channels 1-7 and 9-15 is almost exclusively used for the 21-cm 7-Beam system. All other receivers are attached to channels 8+16. For each channel the **mode** can be changed with the command | The various IFs coming from the receivers are fed into the 16-channel MultiFiBa, which allows to apply several internal bandpass filters and attenuation. Channels 1-7 and 9-15 is almost exclusively used for the 21-cm 7-Beam system. All other receivers are attached to channels 8+16. For each channel the **mode** can be changed with the command | ||
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| <code>SXXNNNZ</code> | <code>SXXNNNZ</code> | ||
| - | where XX stands for the channel which one would like to change and NNN is a three-byte code for the mode. XX can be 01 to 16, or 99 (for all channels. Typical modes are: | + | where XX stands for the channel which one would like to change and NNN is a three-byte code for the mode. XX can be 01 to 16, or 99 (for all channels. **Note, that the MultiFiBa got a very slow processing unit, so sometimes it may take a while until the requested mode is set.** Typical modes are: |
| - | ^Mode^Channels^IF^Bandwidth^Attenuation-enabled^Comment^ | + | ^Mode^Channels^IF name^IF range^Bandwidth^Attenuation^Comments^ |
| - | |097|8+16|VLBA IF|100 MHz|yes| | | + | ^ ^ ^ ^[MHz]^[MHz]^enabled^ ^ |
| - | |185|8+16|VLBA IF|500 MHz|yes| | | + | |216|8+16|VLBA IF|700-800|100|yes| | |
| - | |128|8+16|Narrowband (SB)|100 MHz|yes| | | + | |185|8+16|VLBA IF|500-1000|500|yes| | |
| - | |134|8+16|Narrowband (SB)|50 MHz|yes|needs change in .front-files| | + | |000|8+16|Narrowband (SB)|100-200|100|yes| | |
| - | |128|1-7,9-15|7-Beam IF|100 MHz|yes|exclusively for 21-cm 7-beam| | + | |006|8+16|Narrowband (SB)|150-200|50|yes|needs change in .front-files (ULO)| |
| - | |161|1-7,9-15|7-Beam IF|300 MHz(*)|yes|exclusively for 21-cm 7-beam| | + | |128|1-7,9-15|7-Beam IF|100-200|100|yes|exclusively for 21-cm 7-beam| |
| - | |033|8+16|Optical|2/2.5 GHz|no|used for UBB/new K-band| | + | |161|1-7,9-15|7-Beam IF|0-300|300(*)|yes|exclusively for 21-cm 7-beam| |
| - | |161|8+16|Baseband|1 GHz(+)|yes|mainly for VLBI and pulsars| | + | |033|8+16|Optical|0-2500|2500|no|used for UBB/new K-band| |
| + | |161|8+16|Baseband|0-1000|1000(+)|yes|mainly for VLBI and pulsars| | ||
| (*) 300 MHz from 7-Beam Rx/IF, MultiFiBa only applies 2.5 GHz lowpass\\ | (*) 300 MHz from 7-Beam Rx/IF, MultiFiBa only applies 2.5 GHz lowpass\\ | ||
| (+) 1GHz from IF, MultiFiBa only applies 2.5 GHz lowpass | (+) 1GHz from IF, MultiFiBa only applies 2.5 GHz lowpass | ||
| Line 41: | Line 42: | ||
| - | ===== Wiring schemes for spectroscopy ===== | + | ===== MultiFiBa technical scheme ===== |
| - | **Outdated. Will be updated soon.** | + | {{:information_for_astronomers:user_guide:bsb_multifiba_rev.4_20141120.png?1000|}}\\ |
| + | {{:information_for_astronomers:user_guide:bsb_multifiba_rev.4_20141120.pdf|}} | ||
| - | === XFFTS 100/500 MHz Bandwidths === | ||
| - | {{:information_for_astronomers:user_guide:xffts_100_500mhz.png?800|}} | ||
| - | === XFFTS 2 GHz Bandwidth === | ||
| - | |||
| - | {{:information_for_astronomers:user_guide:xffts_2ghz.png?800|}} | ||
| - | |||
| - | === AFFTS 7-Beam (100 MHz) === | ||
| - | |||
| - | {{:information_for_astronomers:user_guide:affts_7beam.png?800|}} | ||
| - | |||
| - | === AFFTS channels 8 and 16 (100 MHz) === | ||
| - | |||
| - | {{:information_for_astronomers:user_guide:affts_8_16_100mhz.png?800|}} | ||
| - | |||
| - | ===== Pictures ===== | ||
| - | |||
| - | {{:information_for_astronomers:user_guide:xffts_photo.png?518|}}\\ | ||
| - | {{:information_for_astronomers:user_guide:affts_photo.png?556|}}\\ | ||
| - | {{:information_for_astronomers:user_guide:multifiba1_rename.png?768|}}\\ | ||
| - | {{:information_for_astronomers:user_guide:multifiba2_rename.png?576|}} | ||
information_for_astronomers/user_guide/signalpathsetup.1416522363.txt.gz · Last modified: 2014/11/20 23:26 by bwinkel
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