Application of Bat Algorithm on the Design of a Linear Microstrip Antenna Array for Pattern Nulling

this paper presents an application of Bat optimization algorithm on the pattern nulling technique for imposing single null at side lobes. A linear microstrip antenna array has been proposed to deploy the theory from Bat algorithm. The proposed array consists of 10 printed vertical antenna elements based on RO4003C substrate with the size of 160 x 450 x 1.524 mm3. When the array is fed by an ideal source, the simulated radiation pattern meets the requirement in term of null placement. A full design of the array for imposing a single null at the first side lobe has been proposed and investigated. Amplitude excitation weights are divided by a series feeding network. To improve the gain, a back reflector constructed on Fr-4 substrate with the size of 213 x 503 x 1.6 mm3has been used. The simulation results show that the first side lobe level can be suppressed to -40 dB at the frequency of 3.5 GHz while the maximum gain is 17.7 dBi. The simulated and measured reflection coefficients indicate that S1,1is equal -10 dB in the frequency range of 3.26-3.78 GHz. With these characteristics, the proposed antenna array is a good candidate for wireless systems in the C band.