Optimization Method for Pointing Accuracy of Broadband Digital Delay Array

This paper analyzes the causes of pointing error for broadband arrays using digital time delayers at the channel level. The effects of different quantization methods such as conventional truncation method, rounding method, and random method on the beam pointing error are given. According to the principle of equal phase plane, an online optimization method of beam pointing based on linear regression is proposed and designed. The effectiveness of the method is verified in one-dimensional linear array firstly, and then extended to the application of two-dimensional planar array. The method can effectively reduce the pointing error caused by the quantization step of the digital delayers. The beam pointing accuracy of the array can be improved an order of magnitude. In this paper, a 1×12 element linear array and a 8×8 element planar array are used as examples to verify the effectiveness of the method. The simulated results show that the average beam pointing errors of the two arrays are reduced from the original 0.167 and 0.109 to 0.010 and 0.011, respectively. The optimization method proposed in this paper has important engineering application value for improving the comprehensive performance of broadband radar, communication and detection systems using phased array technology.