Low-Profile Terahertz Radar Based on Broadband Leaky-Wave Beam Steering

We demonstrate short-range terahertz radar based on a leaky-wave antenna with a beam steering capability. As a proof of concept, we develop a microstrip-based periodic leaky-wave antenna driven by a vector network analyzer. By sweeping the frequency from 235 to 325 GHz, beam steering from -23° to +15° across the broadside can be achieved with a nearly constant beam width of 4°. Small target detection is demonstrated by locating a metal cylinder with a diameter of 12 mm placed 46-86 mm in front of the antenna with a mean error of 2.4 mm. The use of a leaky-wave antenna can pave the way for developing a low-loss, low-profile, and wide-aperture terahertz radar. Importantly, it can be integrated with a solid-state source and a detector. The proposed approach is particularly promising for use with emerging small devices such as drones or wearable devices, where millimeter-wave radar is not suitable in terms of the resolution and system footprint.

[1]  Juan Sebastian Gomez-Diaz,et al.  Sinusoidally Modulated Graphene Leaky-Wave Antenna for Electronic Beamscanning at THz , 2013, IEEE Transactions on Terahertz Science and Technology.

[2]  D. Donoho,et al.  Uncertainty principles and signal recovery , 1989 .

[3]  K. Solbach,et al.  Transmission Line Modeling and Asymptotic Formulas for Periodic Leaky-Wave Antennas Scanning Through Broadside , 2011, IEEE Transactions on Antennas and Propagation.

[4]  A. Rogalski,et al.  Terahertz detectors and focal plane arrays , 2011 .

[5]  Henry Jasik,et al.  Antenna engineering handbook , 1961 .

[6]  Hiroyuki Shinoda,et al.  Terahertz beam focusing based on plasmonic waveguide scattering , 2012 .

[7]  N. Llombart,et al.  Penetrating 3-D Imaging at 4- and 25-m Range Using a Submillimeter-Wave Radar , 2008, IEEE Transactions on Microwave Theory and Techniques.

[8]  J. R. James,et al.  Microstrip antennas and arrays. Part 2: New array-design technique , 1977 .

[9]  Peter Uhd Jepsen,et al.  Terahertz radar cross section measurements , 2010 .

[10]  B. Williams.  Terahertz quantum cascade lasers , 2007, 2008 Asia Optical Fiber Communication & Optoelectronic Exposition & Conference.

[11]  A. Sengupta,et al.  Characterisation of olefin copolymers using terahertz spectroscopy , 2006 .

[12]  Nuria Llombart,et al.  THz Imaging Radar for Standoff Personnel Screening , 2011, IEEE Transactions on Terahertz Science and Technology.

[13]  B. M. Albaker,et al.  Unmanned aircraft collision detection and resolution: Concept and survey , 2010, 2010 5th IEEE Conference on Industrial Electronics and Applications.

[14]  Ho-Jin Song,et al.  300-GHz Microstrip-to-Waveguide Transition on a Polyimide Substrate Integrated with an LTCC Substrate Integrated Waveguide , 2015, IEICE Trans. Electron..

[15]  N. Kikuma,et al.  Via-hole-less planar microstrip-to-waveguide transition in millimeter-wave band , 2011, 2011 China-Japan Joint Microwave Conference.

[16]  J. R. James,et al.  Microstrip Antenna Theory and Design , 1981 .

[17]  H. Shinoda,et al.  Terahertz plasmonic Bessel beamformer , 2015 .

[18]  D. Jackson,et al.  A Novel Technique for Open-Stopband Suppression in 1-D Periodic Printed Leaky-Wave Antennas , 2009, IEEE Transactions on Antennas and Propagation.

[19]  R. A. Johnson,et al.  Antenna engineering handbook /2nd edition/ , 1984 .

[20]  T. Itoh,et al.  Leaky and bound modes in terahertz metasurfaces made of transmission-line metamaterials , 2013 .

[21]  A. J. Zuckerwar,et al.  Atmospheric absorption of sound: Further developments , 1995 .

[22]  N. Krumbholz,et al.  Scaled Bistatic Radar Cross Section Measurements of Aircraft With a Fiber-Coupled THz Time-Domain Spectrometer , 2012, IEEE Transactions on Terahertz Science and Technology.

[23]  D. Jackson,et al.  Leaky‐Wave Antennas , 2008 .

[24]  Yasuaki Monnai,et al.  Focused terahertz waves generated by a phase velocity gradient in a parallel-plate waveguide. , 2015, Optics express.

[25]  Safumi Suzuki,et al.  650-GHz Resonant-Tunneling-Diode VCO With Wide Tuning Range Using Varactor Diode , 2014, IEEE Electron Device Letters.

[26]  G. Ducournau,et al.  Thin film transmission lines using cyclic olefin copolymer , 2011, 2011 International Conference on Infrared, Millimeter, and Terahertz Waves.

[27]  Yuh-Jing Hwang,et al.  Fiber-based swept-source terahertz radar. , 2010, Optics letters.

[28]  D. Jackson,et al.  A New Brillouin Dispersion Diagram for 1-D Periodic Printed Structures , 2007, IEEE transactions on microwave theory and techniques.

[29]  Tatsuo Itoh,et al.  Dielectric waveguide-based leaky-wave antenna at 212 GHz , 1998 .

[30]  Terahertz laminated-structure polarizer with high extinction ratio and transmission power , 2015 .

[31]  T. Kurner,et al.  Short-Range Ultra-Broadband Terahertz Communications: Concepts and Perspectives , 2007, IEEE Antennas and Propagation Magazine.

[32]  Paolo Baccarelli,et al.  1-D Combline Leaky-Wave Antenna With the Open-Stopband Suppressed: Design Considerations and Comparisons With Measurements , 2013, IEEE Transactions on Antennas and Propagation.

[33]  Tatsuo Itoh,et al.  Terahertz quantum-cascade laser with active leaky-wave antenna , 2011 .

[34]  Safumi Suzuki,et al.  Oscillation up to 1.92 THz in resonant tunneling diode by reduced conduction loss , 2016 .

[35]  Nuria Llombart,et al.  Time-Delay Multiplexing of Two Beams in a Terahertz Imaging Radar , 2010, IEEE Transactions on Microwave Theory and Techniques.

[36]  Daniel M. Mittleman,et al.  Frequency-division multiplexing in the terahertz range using a leaky-wave antenna , 2015, Nature Photonics.