A Genetic Approach to MTI Filter Design with Nonuniform Sampling

In modern radar systems, moving target indicator (MTI) filters are generally used to remove the echo caused by fixed unwanted targets, as well as signal-dependent interference (i.e., clutter). The MTI filters are simply defined as the weighted sum of pulses with tuned periods. Namely, the design parameters that mainly characterize such filters are the weighting coefficients and interpulse periods (IPPs). In this paper, a two-step algorithm is introduced to calculate the design parameters. As to the weighting coefficients, the deviation of the designed passband response is optimized using the least square criterion. As to the IPPs, the minimum of the signal-to-clutter ratio (SCR) in the passband is maximized utilizing the genetic algorithm. In order to make control over the stopband, particular constraints is enforced to induce nulls at limited numbers of frequency spots in the clutter rejection band. The performance assessments illustrates the effectiveness of the genetic least square (GLS) method, as compared with other existing ones.