Research On Wide-angle And Low-profile Phased Array Antenna Based On Tight Couplin

The benefits of phased array antennas,which include high gain and rapid beam scanning,have led to their widespread use in a variety of electronic devices.In recent years,in tandem with the fast expansion of the electronic information sector,an increase in the need of the performance of electronic systems has also taken place.Because phased array antennas are such an essential component of electronic systems,it is unavoidable that they will need to satisfy more stringent standards,such as having a smaller profile height,a wider scanning angle,and a greater bandwidth.In recent years,there has been a significant development in the technology that makes it possible to realize ultra-wideband phased arrays by making use of mutual coupling between array parts.The phased array antenna that is based on tight coupling technology has the features of having a low profile,big beam scanning Angle,and wide bandwidth.This antenna is also a hot point in the research field of ultra-wideband phased arrays.In the field of tightly coupled phased array,many researchers have made a great deal of effort in order to achieve low profile,wide Angle scanning,and ultra-broadband.These goals have been accomplished through the utilization of various wide Angle matching layers,the introduction of parallel capacitors in the antenna layer,the addition of elaborate ferrite or resistor sheet between the floor and the antenna layer,and a great deal of other similar techniques.These research have the potential to enhance,at least to some degree,the performance of densely linked array antennas.This thesis builds on the work of earlier researchers by beginning with the fundamental notion of tight coupling.Its objectives are to obtain a reduced profile and a wider scanning angle.At long last,a low-profile wideangle scanning tight-coupled phase-controlled antenna has been constructed,and its functionality has been experimentally verified.The findings of the simulation and the measurement are essentially compatible with one another,and in comparison to the existing literature,its performance has shown some improvements.The following is a synopsis of the main arguments presented in the thesis:The research history of the tightly coupled phased array is presented first,followed by an explanation of the importance of the research on the tightly coupled phased array.This article provides an introduction to the development history of the closely linked phased array as well as the current research status.After that,the operating concept of the tightly coupled phased array is described,as well as the procedure for doing an analysis of the tightly coupled phased array using the equivalent circuit model.The second step is an explanation of the design procedure for the dipole layer.In the first step of the process,an investigation into how altering the form of the dipole itself might affect its equivalent reactance is carried out.After that,an investigation into the connection that exists between the thickness of the newly introduced dielectric sheet and the input impedance of the tightly linked phased array is carried out.It has been discovered that the use of dielectric sheet,despite the fact that it has the potential to make the input impedance of the antenna smoother,also results in an increase in the profile height of the antenna.This,in turn,causes the array to become thicker and more expensive.It is then suggested that adding a parasitic metal patch to the dipole layer is analogous to inserting capacitance and inductance into the equivalent circuit model of the closely coupled array.As a result,the input impedance of the antenna would be effectively reduced.At the same time,it is also analyzed that when the parasitic metal patch is added to the dipole layer,if the shunt capacitor introduced is too large,the high frequency inductance will be increased,which will result in high frequency mismatch and limited bandwidth.This is because the high frequency inductance is proportional to the value of the shunt capacitor.Thirdly,a Marchand Baron with an impedance conversion function is developed according to the change rule of the input impedance of the antenna after the parasitic metal patch has been added.This design is based on the change rule.Following the presentation of the impedance conversion line design approach,the design is then carried out in accordance with the Chebyshev multi-node impedance converter concept.Second,the Marchand Balun design idea is presented,and a Marchand Balun that is based on an open microstrip line is constructed.In the end,the two simulations are combined,and then the design parameters of the Barron are optimized further in accordance with the variation law of the input impedance of the antenna port.In the end,a full-wave simulation is performed by integrating Barron with the dipole layer of the antenna.This allows for the construction of a low-profile wide-angle scanning ultra-wideband tightly linked phased array.In conclusion,in order to validate the simulation results of the designed array,an8x8 model was constructed,its reflection coefficient was analyzed using a vector network analyzer,and the direction diagram was examined in a microwave darkroom.All of these steps were carried out in order to verify the simulation results.The fact that the findings of the final test were essentially consistent with the results of the simulation demonstrated that the design was right.