Periodic template compensation phase feeding method for phased array antenna

Abstract To minimise the beam‐pointing error caused by the digital phase shifter in phased array antenna systems, a periodic template compensation (PTC) phase feeding algorithm is proposed in this study. In the PTC, the phase quantisation error period of the rounding method in the u‐v dimension is derived as Pu and Pv. Then, the beam‐pointing area is divided into multiple regions with a size of Pu × Pv. In the phase quantisation error period of {u,v}∈{[0,Pu), [0,Pv)}, a sequential phase feeding method is derived to minimise the beam‐pointing error and a compensation matrix template is constructed. The phase feeding code of the PTC is the summation of that of the rounding method and corresponding compensation vector selected periodically from the compensation matrix template. Simulation results show that the maximal beam‐pointing error of the PTC method is 26% of that of the rounding method for a 16 × 16 rectangular array. Azimuth measurement results from a phased array radar system verify the efficiency of the proposed method. Involving only integer multiplication, addition and shift processing, implementing the PTC algorithm in phased array systems is very easy.