A New Approach to Synthesis of a Quasi Non-Uniform Leaky Wave Antenna

In this paper, a closed-form mathematical formula has been presented using of the proposed periodic structure E-field distribution, that helps designers to calculate the width of the slots in Quasi Non-Uniform Leaky Wave Antenna (QNULWA). This method is based on two steps. In the first step, some important parameters for the proposed antenna design will be extracted using simulation. In the second step, by solving a discrete differential equation, a general relation will be obtained for these types of antennas. This method has been investigated in the case of slot LWA families. A Leaky wave antenna has been synthesized in the 15.5- 18 GHz frequency range for Gaussian radiation pattern. The results of simulation and antenna design will be very close to each other in 2.5 GHz Bandwidth (15.5 - 18 GHz), which shows the accuracy of this formula. Also, By changing the frequency range 2-5 GHz, the main lobe direction of the antenna will scan the space approximately 10 degrees(from 63 to 73 degree). The antenna has an SLL value of about -25 dB and 13 dB Gain at whole band 15.5-18 GHz . The obtained formula helps the antenna designers to calculate the dimensions this type of antenna for any pattern distribution.