2$\times$ 2-Slot Element for 60-GHz Planar Array Antenna Realized on Two Doubled-Sided PCBs Using SIW Cavity and EBG-Type Soft Surface fed by Microstrip-Ridge Gap Waveguide

A wideband 2 ×2-slot element for a 60-GHz antenna array is designed by making use of two double-sided printed circuit boards (PCBs). The upper PCB contains the four radiating cavity-backed slots, where the cavity is formed in substrate-integrated waveguide (SIW) using metalized via holes. The SIW cavity is excited by a coupling slot. The excitation slot is fed by a microstrip-ridge gap waveguide formed in the air gap between the upper and lower PCBs. The lower PCB contains the microstrip line, being short-circuited to the ground plane of the lower PCB with via holes, and with additional metalized via holes alongside the microstrip line to form a stopband for parallel-plate modes in the air gap. The designed element can be used in large arrays with distribution networks realized in such microstrip-ridge gap waveguide technology. Therefore, the present paper describes a generic study in an infinite array environment, and performance is measured in terms of the active reflection coefficient S11 and the power lost in grating lobes. The study shows that the radiation characteristics of the array antenna is considerably improved by using a soft surface EBG-type SIW corrugation between each 2 ×2-slot element in E-plane to reduce the mutual coupling. The study is verified by measurements on a 4 ×4 element array surrounded by dummy elements and including a transition to rectangular waveguide WR15.

[1]  Eva Rajo-Iglesias,et al.  Design and experimental verification of ridge gap waveguide in bed of nails for parallel-plate mode suppression , 2011 .

[2]  O. Quevedo-Teruel,et al.  Mutual Coupling Reduction in Patch Antenna Arrays by Using a Planar EBG Structure and a Multilayer Dielectric Substrate , 2008, IEEE Transactions on Antennas and Propagation.

[3]  Wei Hong,et al.  Design and Experimental Verification of Compact Frequency-Selective Surface With Quasi-Elliptic Bandpass Response , 2007, IEEE Transactions on Microwave Theory and Techniques.

[4]  E. Rajo-Iglesias,et al.  Local Metamaterial-Based Waveguides in Gaps Between Parallel Metal Plates , 2009, IEEE Antennas and Wireless Propagation Letters.

[5]  Eva Rajo-Iglesias,et al.  Planar Dual-Mode Horn Array With Corporate-Feed Network in Inverted Microstrip Gap Waveguide , 2014, IEEE Transactions on Antennas and Propagation.

[6]  A. Kishk,et al.  Special Issue on Artificial Magnetic Conductors, Soft/Hard Surfaces, and Other Complex Surfaces , 2005 .

[7]  Young Sik Kim,et al.  Two-layer slotted-waveguide antenna array with broad reflection/gain bandwidth at millimetre-wave frequencies , 2004 .

[8]  Jian Yang,et al.  Microstrip-Ridge Gap Waveguide–Study of Losses, Bends, and Transition to WR-15 , 2014, IEEE Transactions on Microwave Theory and Techniques.

[9]  H. Uchimura,et al.  Development of the "laminated waveguide" , 1998, IMS 1998.

[10]  P. Kildal,et al.  Wide-Band Slot Antenna Arrays With Single-Layer Corporate-Feed Network in Ridge Gap Waveguide Technology , 2014, IEEE Transactions on Antennas and Propagation.

[11]  Per-Simon Kildal,et al.  Three metamaterial-based gap waveguides between parallel metal plates for mm/submm waves , 2009, 2009 3rd European Conference on Antennas and Propagation.

[12]  J. Laskar,et al.  Radiation-pattern improvement of patch antennas on a large-size substrate using a compact soft-surface structure and its realization on LTCC multilayer technology , 2005, IEEE Transactions on Antennas and Propagation.

[13]  Eva Rajo-Iglesias,et al.  Numerical studies of bandwidth of parallel-plate cut-off realised by a bed of nails, corrugations and mushroom-type electromagnetic bandgap for use in gap waveguides , 2011 .

[14]  G. Luo,et al.  Development of Low Profile Cavity Backed Crossed Slot Antennas for Planar Integration , 2009, IEEE Transactions on Antennas and Propagation.

[15]  M. Baquero,et al.  Gap Waveguides Using a Suspended Strip on a Bed of Nails , 2011, IEEE Antennas and Wireless Propagation Letters.

[16]  Byungje Lee,et al.  Cavity-backed planar slot array antenna with a single waveguide-fed sub-array , 2004, IEEE Antennas and Propagation Society Symposium, 2004..

[17]  波尔-西蒙·基尔代尔,et al.  Waveguides and transmission lines in gaps between parallel conducting surfaces , 2015 .

[18]  J. Hirokawa,et al.  A low-cost and very compact wireless terminal integrated on the back of a waveguide planar array for 26 GHz band fixed wireless access (FWA) systems , 2005, IEEE Transactions on Antennas and Propagation.

[19]  Per-Simon Kildal,et al.  Resemblance between gap waveguides and hollow waveguides , 2013 .

[20]  M. Ando,et al.  Center feed single layer slotted waveguide array , 2006, IEEE Transactions on Antennas and Propagation.

[21]  Ke Wu,et al.  Guided-wave and leakage characteristics of substrate integrated waveguide , 2005, IMS 2005.

[22]  E. Rajo-Iglesias,et al.  New Microstrip Gap Waveguide on Mushroom-Type EBG for Packaging of Microwave Components , 2012, IEEE Microwave and Wireless Components Letters.

[23]  A. A. Kishk,et al.  Narrow-Band Microwave Filter Using High-Q Groove Gap Waveguide Resonators With Manufacturing Flexibility and No Sidewalls , 2012, IEEE Transactions on Components, Packaging and Manufacturing Technology.

[24]  M. Ando,et al.  Double-Layer Full-Corporate-Feed Hollow-Waveguide Slot Array Antenna in the 60-GHz Band , 2011, IEEE Transactions on Antennas and Propagation.