Adaptive antenna array for IEEE802.16e base station in the presence of multipath and interference and considering mutual coupling effects

In this paper, an adaptive antenna array beamformer for the base station of mobile WiMAX (IEEE802.16e) is designed. This antenna is considered for uplink beamforming in presence of interferer signals and noisy multipath channel. Complex excitation coefficients of the array elements are controlled adaptively to track the mobile user signal considering channel and interference variations. Uplink preamble symbols are used as training sequence in the beamforming algorithm. The proposed antenna array configuration is planar microstrip antenna array consisting of 9 rectangular patches. This array is designed for operating at mobile WiMAX licensed band of 3.5 GHz. The complex active element patterns are achieved by full wave analysis of the array in Ansoft HFSS. The mutual coupling among the elements of the array is considered thus making the beamformer robust against coupling effects. The performance of the system is evaluated by simulating the physical layer of IEEE802.16e for uplink transmission applying adaptive antenna beamformer.