Spatially Decoupling of CP Antennas Based on FSS for 30-GHz MIMO Systems

In this paper, an effective approach for mitigating the near-field coupling between four-port circularly polarized (CP) antennas in a 30-GHz multiple-input, multiple-output (MIMO) system is suggested and investigated. This is obtained by incorporating a two-layer transmission-type frequency selective surface (FSS) superstrate based on planar crossed-dipole metal strips. This paper presents a comparison between the mutual coupling when the patches are radiating in free space and in the presence of the FSS layers. The simulated results, when the FSS layers are applied, show an average of 6–12-dB improvement in the isolation between four adjacent CP-MIMO antennas. In addition, an accurate study is carried out on the insignificant reflections produced by the FSS layers to redirect those and also prevent any interference. The proposed $2\times 2$ CP-MIMO antenna along with the superstrate is implemented and tested to validate the simulation results. Experimental results of the coupling and reflection coefficients and axial ratio show an acceptable agreement with the corresponding simulated ones.

[1]  R. Gonzalo,et al.  A 250 GHz Subharmonic Mixer Design Using EBG Technology , 2007, IEEE Transactions on Antennas and Propagation.

[2]  Z. Nie,et al.  An Efficient Decoupling Feeding Network for Microstrip Antenna Array , 2015, IEEE Antennas and Wireless Propagation Letters.

[3]  Nemai Chandra Karmakar,et al.  Frequency Selective Surface for reducing mutual coupling in antenna arrays , 2011, Asia-Pacific Microwave Conference 2011.

[4]  H. S. Farahani,et al.  Mutual Coupling Reduction in Patch Antenna Arrays Using a UC-EBG Superstrate , 2010, IEEE Antennas and Wireless Propagation Letters.

[5]  Danilo Erricolo,et al.  Metamaterial Spheroidal Cavity to Enhance Dipole Radiation , 2015, IEEE Transactions on Antennas and Propagation.

[6]  Alexander B. Yakovlev,et al.  Reduction of Mutual Coupling Between Neighboring Strip Dipole Antennas Using Confocal Elliptical Metasurface Cloaks , 2015, IEEE Transactions on Antennas and Propagation.

[7]  A. Pirhadi,et al.  Wideband High Directive Aperture Coupled Microstrip Antenna Design by Using a FSS Superstrate Layer , 2012, IEEE Transactions on Antennas and Propagation.

[8]  Tzyh-Ghuang Ma,et al.  Very Compact Fully Lumped Decoupling Network for a Coupled Two-Element Array , 2016, IEEE Antennas and Wireless Propagation Letters.

[9]  Christos Oikonomopoulos-Zachos.  Double layer compact four-port antenna using a symmetrical feeding technique for future MIMO antenna systems at 5.6GHz , 2010, 2010 IEEE Antennas and Propagation Society International Symposium.

[10]  Qian Xu,et al.  Reduction of mutual coupling between closely-packed antenna elements using defected ground structure , 2009, 2009 3rd IEEE International Symposium on Microwave, Antenna, Propagation and EMC Technologies for Wireless Communications.

[11]  G. Dubost.  Influence of surface wave upon efficiency and mutual coupling between rectangular microstrip antennas , 1990, International Symposium on Antennas and Propagation Society, Merging Technologies for the 90's.

[12]  Tayeb A. Denidni,et al.  Multi-Band Miniaturized Antenna Loaded by ZOR and CSRR Metamaterial Structures With Monopolar Radiation Pattern , 2014, IEEE Transactions on Antennas and Propagation.

[13]  Xiaoxing Yin,et al.  Mutual Coupling Suppression Between Two Closely Spaced Microstrip Antennas With an Asymmetrical Coplanar Strip Wall , 2016, IEEE Antennas and Wireless Propagation Letters.

[14]  Rahul Porwal,et al.  MIMO OFDM Space Time Coding - Spatial Multiplexing Increasing Performance and Spectral Efficiency in Wireless Systems , 2014 .

[15]  D. Guha,et al.  Concentric Ring-Shaped Defected Ground Structures for Microstrip Applications , 2006, IEEE Antennas and Wireless Propagation Letters.

[16]  David M. Pozar,et al.  Anomalous mutual coupling between microstrip antennas , 1994 .

[17]  Shyh-Jong Chung,et al.  A Decoupling Technique for Increasing the Port Isolation Between Two Strongly Coupled Antennas , 2008, IEEE Transactions on Antennas and Propagation.

[18]  David R. Jackson,et al.  Mutual coupling between reduced surface-wave microstrip antennas , 2000 .

[19]  Ke-Li Wu,et al.  A Coupled Resonator Decoupling Network for Two-Element Compact Antenna Arrays in Mobile Terminals , 2014, IEEE Transactions on Antennas and Propagation.

[20]  M. Akbari,et al.  Gain Enhancement of Circularly Polarized Dielectric Resonator Antenna Based on FSS Superstrate for MMW Applications , 2016, IEEE Transactions on Antennas and Propagation.

[21]  Sergey Pivnenko,et al.  Coupling Reduction Between Dipole Antenna , 2009 .

[22]  Abhishek Kumar,et al.  ANALYSIS OF FREQUENCY SELECTIVE SURFACES FOR RADAR ABSORBING MATERIALS , 2012 .

[23]  Yingzeng Yin,et al.  EIGENMODE DECOUPLING FOR MIMO LOOP-ANTENNA BASED ON 180 - COUPLER , 2011 .

[24]  Tie Jun Cui,et al.  Reduction of the spatially mutual coupling between dual-polarized patch antennas using coupled metamaterial slabs , 2016, Scientific reports.

[25]  Tayeb A. Denidni,et al.  Millimeter-Wave Compact EBG Structure for Mutual Coupling Reduction Applications , 2015, IEEE Transactions on Antennas and Propagation.

[26]  Theodore S. Rappaport,et al.  Millimeter Wave Mobile Communications for 5G Cellular: It Will Work! , 2013, IEEE Access.

[27]  Tayeb A. Denidni,et al.  Analytic study on CP enhancement of millimeter wave DR and patch subarray antennas , 2017 .

[28]  C. Medeiros,et al.  Evaluation of a New Wideband Slot Array for MIMO Performance Enhancement in Indoor WLANs , 2011, IEEE Transactions on Antennas and Propagation.

[29]  Ekmel Ozbay,et al.  Decoupling of multifrequency dipole antenna arrays for microwave imaging applications , 2010 .

[30]  Mario Sorolla,et al.  Enhanced patch-antenna performance by suppressing surface waves using photonic-bandgap substrates , 1999 .