Calibration of a Digital Phased Array by Using NCO Phase Increasing Algorithm

Lijie YANG, Ruirui DANG, Chunyi SONG, Zhiwei XU

Summary :

All digital phased arrays generate multiple beams concurrently through the digital beam forming technique, which features digital processing with multiple identical receiving/transmitting channels in RF or microwave frequencies. However, the performance of this process strongly depends on accurately matching the amplitude and phase of the channels, as mismatching is likely to degrade radar performance. In this paper, we present a method to calibrate receiving array by using NCO phase increasing algorithm, which simplifies array system by removing the external far-field calibration signals often needed in array systems. Both analysis and simulation results suggest that the proposed method attains better calibration performance than existing approaches, even with a low SNR input signal. Experiments also varify that the proposed calibration method is effective and achieves a desired radiation pattern. We can further boost calibration accuracy and reduce calibration time by programming NCO phase width and NCO phase resolution.

• Publication: IEICE TRANSACTIONS on Communications Vol.E102-B No.4 pp.948-955
• Publication Date: 2019/04/01
• Publicized: 2018/10/15
• Online ISSN: 1745-1345
• DOI: 10.1587/transcom.2018EBP3120
• Type of Manuscript: PAPER
• Category: Sensing

Authors

Lijie YANG
  Zhejiang University,the Key Laboratory of Ocean Observation-Imaging Testbed of Zhejiang Province
Ruirui DANG
  Zhejiang University,the Key Laboratory of Ocean Observation-Imaging Testbed of Zhejiang Province
Chunyi SONG
  Zhejiang University,the Key Laboratory of Ocean Observation-Imaging Testbed of Zhejiang Province
Zhiwei XU
  Zhejiang University,the Key Laboratory of Ocean Observation-Imaging Testbed of Zhejiang Province

Keyword

amplitude-phase error,  internal calibration,  digital phased array,  radiation pattern