TY - JOUR
T1 - Ethernet-based DAQ system for QUIET-II detectors
AU - Nagai, M.
AU - Ishidoshiro, K.
AU - Higuchi, T.
AU - Ikeno, M.
AU - Hasegawa, M.
AU - Hazumi, M.
AU - Tajima, O.
AU - Tanaka, M.
AU - Uchida, T.
N1 - Funding Information:
Acknowledgements We acknowledge assistance by Open Source Consortium of Instrumentation for useful discussions with FPGA users. This work was supported by MEXT and JSPS with Grant-in-Aid for Scientific Research on Innovative Areas 21111002.
PY - 2012/6
Y1 - 2012/6
N2 - The B-modes in cosmic microwave background polarization are a smoking gun for the inflationary universe. For the detection of the B-modes, having a large detector array is a generic approach since the B-modes is so faint pattern (Tb ≲ 0.1 μK). The Q/U Imaging ExperimenT Phase-II (QUIET-II) is proposed to search the B-modes, using an array with 500 HEMT-based polarimeters. Each polarimeter element has 4-outputs, therefore we have to manage 2000 channels in total. We developed a scalable DAQ system based on TCP/Ethernet for QUIET-II. The DAQ system is composed of the polarimeters, ADC boards, a Master Clock and a control computer (PC). The analog signals from the polarimeters are digitized on the ADC boards. On-board demodulation, which synchronizes the phase flip modulations on the polarimeter, extracts the polarized components in the digitized signal. The Master Clock distributes all necessary clocks to the ADC boards as well as the polarimeters. This scheme guarantees the synchronization of the modulations and demodulations. We employed Ethernet-based communication scheme between the data collection program (Collector) on the PC and the ADC boards as well as the Master Clock. Such an Ethernet-based communication scheme allows us to construct a simple structure of the upper level software, which results in the high scalability to increase the number of channels. All basic functions and requirements are confirmed by the laboratory tests; demonstration with test signals as well as the signals from the polarimeters, measurements of the data transfer rate, and the synchronous operation with two ADC boards. Therefore, the DAQ system is confirmed to be suitable for QUIET-II.
AB - The B-modes in cosmic microwave background polarization are a smoking gun for the inflationary universe. For the detection of the B-modes, having a large detector array is a generic approach since the B-modes is so faint pattern (Tb ≲ 0.1 μK). The Q/U Imaging ExperimenT Phase-II (QUIET-II) is proposed to search the B-modes, using an array with 500 HEMT-based polarimeters. Each polarimeter element has 4-outputs, therefore we have to manage 2000 channels in total. We developed a scalable DAQ system based on TCP/Ethernet for QUIET-II. The DAQ system is composed of the polarimeters, ADC boards, a Master Clock and a control computer (PC). The analog signals from the polarimeters are digitized on the ADC boards. On-board demodulation, which synchronizes the phase flip modulations on the polarimeter, extracts the polarized components in the digitized signal. The Master Clock distributes all necessary clocks to the ADC boards as well as the polarimeters. This scheme guarantees the synchronization of the modulations and demodulations. We employed Ethernet-based communication scheme between the data collection program (Collector) on the PC and the ADC boards as well as the Master Clock. Such an Ethernet-based communication scheme allows us to construct a simple structure of the upper level software, which results in the high scalability to increase the number of channels. All basic functions and requirements are confirmed by the laboratory tests; demonstration with test signals as well as the signals from the polarimeters, measurements of the data transfer rate, and the synchronous operation with two ADC boards. Therefore, the DAQ system is confirmed to be suitable for QUIET-II.
KW - Cosmic microwave background polarization
KW - Read-out
UR - http://www.scopus.com/inward/record.url?scp=84862615950&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84862615950&partnerID=8YFLogxK
U2 - 10.1007/s10909-012-0561-3
DO - 10.1007/s10909-012-0561-3
M3 - Article
AN - SCOPUS:84862615950
VL - 167
SP - 689
EP - 694
JO - Journal of Low Temperature Physics
JF - Journal of Low Temperature Physics
SN - 0022-2291
IS - 5-6
ER -