Design and implementation of conformal antenna for aircraft applications

Abstract

In this century, the communication plays a vital role in modernizing newlinethe world. Among all the communication technologies aircraft-based newlinecommunication has a crucial role, as it helps in places where human newlineintervention is not possible. The front runner in aircraft-based communication newlineis antenna system. The design of antenna for an aircraft application has its newlineown challenges. Rising fuel prices, demands more payload and more fuelefficient newlineaircraft. Any conformed structure in the fuselage of an aircraft newlinereduces the drag and improves the efficiency. Simultaneously, performance newlineimproved antennas demand less space and helps in increasing the payload. newlineThe conformability requirement of an antenna creates a trade-off among newlinesubstrate thickness, flexibility, gain and bandwidth. Also, the aircraft fuselage newlinebeing an aluminium or carbon fibre composites puts a limit on using newlineconventional bandwidth enhancement techniques. In this thesis, two specific newlineaircraft applications, synthetic aperture radar (SAR) and Direct air to ground newline(DATG), are studied to extract the specification of an antenna. The suitable newlinebandwidth enhanced conformal antennas are designed by structurally newlinemodifying the conventional microstrip patch antenna. Almost four times of newlinebandwidth improvement is achieved. These antennas are designed in C-band newlinein order to have an optimum performance and size. A 1 x 4 phased antenna newlinearray is developed as a prototype and the mutual coupling behaviour is newlinestudied with respect to the spacing between each unit antennas. The beam newlineforming behaviour also exercised on the designed phased array. newline newline