TY - JOUR
T1 - Sensitivity and Distortion Analysis of a 125-GHz Interferometry Radar for Submicrometer Motion Sensing Applications
AU - Rodriguez, Daniel
AU - Li, Changzhi
N1 - Funding Information:
Manuscript received May 3, 2019; revised August 28, 2019 and October 17, 2019; accepted October 25, 2019. Date of publication December 4, 2019; date of current version December 27, 2019. This work was supported by the National Science Foundation (NSF) under Grant ECCS-1808613 and Grant CNS-1718483. This article is an expanded version from the IEEE MTT-S International Microwave Symposium (IMS 2019), Boston, MA, USA, June 2–7, 2019. (Corresponding author: Daniel Rodriguez.) The authors are with the Department of Electrical and Computer Engineering, Texas Tech University, Lubbock, TX 79409 USA (e-mail: daniel-fernando.rodriguez@ttu.edu; changzhi.li@ttu.edu).
Publisher Copyright:
© 1963-2012 IEEE.
PY - 2019/12
Y1 - 2019/12
N2 - In all quadrature direct-conversion receivers, signal deterioration due to I/Q mismatch may happen, causing a mirrored signal to appear superimposed onto the desired signal, thereby destroying the orthogonality of the demodulated signal. This effect strongly affects radar systems over 100 GHz, since they are sensitive to small fabrication errors. In addition, when slow movements are measured with ac-coupled interferometric radars, coupling distortions are observed. In this article, these distortions were analyzed for interferometric radars and then resolved using a novel phase imbalance correction method for a 125-GHz radar. The effectiveness of the proposed solution was verified experimentally for speech information sensing and for small motion detection applications. By successfully measuring a 95-nm sinusoidal movement, the high sensitivity of millimeter-wave (mm-wave) radars was demonstrated. Moreover, noise analyses for small-motion interferometry radars have been presented and a model for sensitivity estimation was proposed.
AB - In all quadrature direct-conversion receivers, signal deterioration due to I/Q mismatch may happen, causing a mirrored signal to appear superimposed onto the desired signal, thereby destroying the orthogonality of the demodulated signal. This effect strongly affects radar systems over 100 GHz, since they are sensitive to small fabrication errors. In addition, when slow movements are measured with ac-coupled interferometric radars, coupling distortions are observed. In this article, these distortions were analyzed for interferometric radars and then resolved using a novel phase imbalance correction method for a 125-GHz radar. The effectiveness of the proposed solution was verified experimentally for speech information sensing and for small motion detection applications. By successfully measuring a 95-nm sinusoidal movement, the high sensitivity of millimeter-wave (mm-wave) radars was demonstrated. Moreover, noise analyses for small-motion interferometry radars have been presented and a model for sensitivity estimation was proposed.
KW - Distortion
KW - I/Q imbalance
KW - interferometric radar
KW - noise
KW - phase mismatch
KW - signal integrity
KW - speech signal detection
UR - http://www.scopus.com/inward/record.url?scp=85077955882&partnerID=8YFLogxK
U2 - 10.1109/TMTT.2019.2951142
DO - 10.1109/TMTT.2019.2951142
M3 - Article
AN - SCOPUS:85077955882
VL - 67
SP - 5384
EP - 5395
JO - IEEE Transactions on Microwave Theory and Techniques
JF - IEEE Transactions on Microwave Theory and Techniques
SN - 0018-9480
IS - 12
M1 - 8922880
ER -