Mutual Coupling in Phased Arrays: A Review

The mutual coupling between antenna elements affects the antenna parameters like terminal impedances, reflection coefficients and hence the antenna array performance in terms of radiation characteristics, output signal-to-interference noise ratio (SINR), and radar cross section (RCS). This coupling effect is also known to directly or indirectly influence the steady state and transient response, the resolution capability, interference rejection, and direction-of-arrival (DOA) estimation competence of the array. Researchers have proposed several techniques and designs for optimal performance of phased array in a given signal environment, counteracting the coupling effect. This paper presents a comprehensive review of the methods that model and mitigate the mutual coupling effect for different types of arrays. The parameters that get affected due to the presence of coupling thereby degrading the array performance are discussed. The techniques for optimization of the antenna characteristics in the presence of coupling are also included

Mutual coupling studies in stacked waveguide slot arrays

Imperial Users onl

Compact and broadband antenna system at UHF

The aim of this research was to study a novel, broadband, low cost, low profile and a high-medium gain antenna in the UHF band. This has been achieved through numerical modelling, theoretical investigation and physical measurements. In this study two commercially available antenna systems are investigated in order to compare and establish potential deficiencies in the UHF antenna systems. A number of disadvantages are resolved within a novel antenna system design. The parametric study is performed for each element of the novel antenna system in order to optimise its overall performance. The indoor and outdoor measurements have been carried out in house, in order to validate the predicted results. The novel antenna system is compared to the most popular and commercially available UHF antenna systems. The study demonstrates that the novel antenna system has clear advantages such as broadband, balanced, compact and low cost when compared to the commercial antenna designs studied here. The comparison of the manufacturers’ data to the measured results shows a good match, validating the outdoor measurements technique used in this research

Cruft Laboratory Semiannual progress report, 1 Jul. - 31 Dec. 1966

Very low frequency signal propagation, electron and solid state physics, automatic control processes, communications and networks, ferromagnetism, and electromagnetic wave

Investigation of a Frequency and Pattern Reconfigurable Slot Array Utilizing Ring Resonator End Loads

Fixed-bandwidth wireless systems are forced to operate in preallocated blocks of frequencies, often wasting valuable spectrum. Whereas, systems with reconfigurable antennas that can tune resonant frequency, polarization, or pattern allow for versatile systems and efficient spectrum use. Reconfigurable antennas have largely been designed using microstrip transmission line structures since they can be easily printed on a dielectric substrate, making the antenna compact, inexpensive to fabricate, and simple to integrate active components in a series configuration. Slotline is similarly easy to fabricate and has been shown to have some advantages over microstrip in applications such as when active components in a shunt configuration are desired. However, not many reconfigurable antenna architectures have been developed in slotline. Additionally, while frequency- and polarization-agile antennas have been reported by many researchers, antennas with both frequency and pattern reconfiguration capabilities are significantly rare. In this thesis, a closed-form analytical solution for a Yagi-Uda array of loaded slot antennas will be presented. This analysis first evaluates each slot antenna using an established transmission line model then calculates the coupling between the elements using the relative induced power on each antenna. Network parameters are then utilized to model the effects the slot antennas have on each other. The Induced EMF method uses the power incident on one antenna due to another to find the mutual impedance between them - allowing the presented method to be generalizable to any Yagi-Uda array of elements where the radiation pattern is known. The network parameters will be shown to provide an array factor for the Yagi-Uda array - predicting the radiative and directive properties of the array in a closed-form analysis. The analysis method will also be shown to predict the input impedance of the driven element of the array, including the impact of mutual coupling from the parasitic elements, across frequency and for arbitrary array spacings - a result that has not been available with previous analysis methods

Application of the moment method to the design of slotted waveguide array antennas

Abstract unavailable please refer to PDF.Science and Engineering Research Counci

Design of radial line slot antennas

Master'sMASTER OF ENGINEERIN

Rigorous analysis of delectric resonator antenna using the method of moments.

by Leung, Kowk-wa.Thesis (Ph.D.)--Chinese University of Hong Kong, 1993.Includes bibliographical references (leaves 207-211).DedicationAcknowledgementsCHAPTERChapter 1. --- INTRODUCTION --- p.1Chapter 2. --- ANALYSIS OF A PROBE-FED HEMISPHERICAL DR ANTENNA --- p.13Chapter 2.1 --- Introduction --- p.13Chapter 2.2 --- Problem Formulation --- p.14Chapter 2.3 --- Single Cavity Mode Approximation --- p.33Chapter 2.3.1 --- Evaluation of Input Impedance --- p.33Chapter 2.3.2 --- Measured and Computed Results --- p.36Chapter 2.4 --- Rigorous Moment Method Solution --- p.47Chapter 2.4.1 --- Efficient Evaluation of GEz --- p.47Chapter 2.4.2 --- Moment Method Formulation for Input Impedance --- p.51Chapter 2.4.3 --- Evaluation of Z-matrix --- p.56Chapter 2.4.4 --- Evaluation of V-matrix --- p.62Chapter 2.4.5 --- Convergence Checks --- p.65Chapter 2.4.6 --- Measured and Computed Results --- p.91Chapter 2.4.7 --- Conclusion --- p.113Chapter 2.5 --- Theoretical Single Cavity Mode Radiation Patterns --- p.114Chapter 2.6 --- Conclusion --- p.117Chapter 3. --- ANALYSIS OF APERTURE COUPLED HEMISPHERICAL DR ANTENNA --- p.118Chapter 3.1 --- Introduction --- p.118Chapter 3.2 --- Problem Formulation --- p.120Chapter 3.3 --- Moment Method Solution --- p.133Chapter 3.4 --- Magnetic Field Green's Function of DR Antenna --- p.138Chapter 3.5 --- Efficient Evaluations of Antenna Green's Function and Yamn --- p.150Chapter 3.5.1 --- Modal Green's function of DR Antenna --- p.150Chapter 3.5.2 --- Evaluation of Yamn --- p.153Chapter 3.6 --- Single Cavity Mode Approximation --- p.155Chapter 3.6.1 --- Evaluation of Input Impedance --- p.155Chapter 3.6.2 --- Measured and Computed Results --- p.157Chapter 3.6.3 --- Conclusion --- p.165Chapter 3.7 --- Exact Modal Solution --- p.166Chapter 3.7.1 --- Convergence Checks --- p.166Chapter 3.7.2 --- Measured and Computed Results --- p.166Chapter 3.7.3 --- Conclusion --- p.187Chapter 3.8 --- Conclusion --- p.188Chapter 4. --- CONCLUSION --- p.189APPENDIX A PROOF OF EQUATION (2-16) --- p.192APPENDIX B DERIVATION OF EQUATION (2-43) --- p.193APPENDIX C DERIVATION OF EQUATION (2-44) --- p.196APPENDIX D PROPAGATION CONSTANT OF FIELDS INSIDE MICROSTRIPLINE --- p.198APPENDIX E NUMERICAL TECHNIQUE OF SPECTRAL DOMAIN INTEGRAL --- p.200APPENDIX F EXPERIMENTAL SET-UP FOR PROBE- FED DR ANTENNA MEASUREMENT --- p.203APPENDIX G EXPERIMENTAL SET-UP FOR APERTURE- COUPLED DR ANTENNA MEASUREMENT --- p.205REFERENCES --- p.207LIST OF PUBLICATIONS PRODUCED DURING THE STUDY A-lINTERNATIONAL AWARD OBTAINED DURING THE STUDY B-