A Design of a Digital Correlator for Microwave Holography Based on the ROACH Platform

Pei Xin; Li Jian; Chen Maozheng; Nie Jun

Astronomical Research and Technology > 2015 > 12(1): 54-62.

Pei Xin, Li Jian, Chen Maozheng, Nie Jun. A Design of a Digital Correlator for Microwave Holography Based on the ROACH Platform[J]. Astronomical Research and Technology, 2015, 12(1): 54-62.

Citation:

Pei Xin, Li Jian, Chen Maozheng, Nie Jun. A Design of a Digital Correlator for Microwave Holography Based on the ROACH Platform[J]. Astronomical Research and Technology, 2015, 12(1): 54-62.

Citation:

Pei Xin, Li Jian, Chen Maozheng, Nie Jun. A Design of a Digital Correlator for Microwave Holography Based on the ROACH Platform[J]. Astronomical Research and Technology, 2015, 12(1): 54-62.

PDF (5297 KB)

A Design of a Digital Correlator for Microwave Holography Based on the ROACH Platform

Xinjiang Astronomical Observatory, Chinese Academy of Sciences, Urumqi 830011, China

More Information

Received Date: March 13, 2014
Revised Date: March 23, 2014
Published Date: January 14, 2015

Graphical Abstract

Abstract

Abstract

We have developed a real-time digital correlator for microwave holography based on the ROACH hardware platform. This correlator has high levels of flexibility and extensibility. First, the correlator does not require any baseband transformation for its input signals. This is achieved by using bandpass sampling to dramatically simplify the hardware system for microwave holography. Second, the sampling rate of the correlator is adjustable within the range 10Mbps to 1000Mbps. Together with the use of a digital frequency mixer and a digital filter, this makes it convenient to adjust bandwidths and frequency resolutions of signals. Our test results show that the correlator has a high measurement precision and a high level of stability, which should ensure accurate and reliable results in future applications.
- Methods of radio astronomy,
- Correlator,
- Microwave holography,
- ROACH,
- FPGA

FullText(HTML)

References (9)

References

[1]	Scott P F, Ryle M. A rapid method for measuring the figure of a radio telescope reflector[J]. Monthly Notices of the Royal Astronomical Society, 1977, 178: 539-545.
[2]	Baars J W M, Lucas R, Mangum J G, et al. Near-field reflector radio holography of large reflector antennas[J]. IEEE Antennas and Propagation Magazine, 2007, 49(5): 24-41.
[3]	王锦清, 范庆元, 李斌. 微波全息测量中相关机的实现[J]. 天文研究与技术——国家天文台台刊, 2009, 6(4): 280-291. Wang Jinqing, Fan Qingyuan, Li Bin. The implementation of a correlator for microwave holographic measurement[J]. Astronomical Research & Technology——Publications of National Astronomical Observatories of China, 2009, 6(4): 280-291.
[4]	CASPER. ROACH[EB/OL]. (2008-11-15) [2014-05-25]. https://casper.berkeley.edu/wiki/ROACH.
[5]	CASPER. IBOB[EB/OL]. (2008-02-26) [2014-05-25]. https://casper.berkeley.edu/wiki/IBOB.
[6]	CASPER. BEE2[EB/OL]. (2007-06-27) [2014-05-25]. https://casper.berkeley.edu/wiki/BEE2.
[7]	Vaughan R G, Scott N L, White D R. The theory of bandpass sampling[J]. IEEE Transactions on Signal Processing, 1991, 39(9): 1973-1984.
[8]	王锦清, 梁世光, 王鹏, 等. 全息测量接收机系统[J]. 天文研究与技术——国家天文台台刊, 2011, 8(3): 242-247. Wang Jinqing, Liang Shiguang, Wang Peng, et al. A holography receiver system[J]. Astronomical Research & Technology——Publications of National Astronomical Observatories of China, 2011, 8(3): 242-247.
[9]	陈蕾, 姚远程. 基于System Generator的数字下变频设计[J].电子设计工程, 2012, 20(24): 74-78. Chen Lei, Rao Yuancheng. Design of digital down-conversion based on the system generator[J]. Electronic Design Engineering, 2012, 20(24): 74-78.