An observer for use with mechanically-steered, limited-scan phased array radars

A state observer is developed to provide the dynamic platform position, rate, and acceleration estimates and predictions required to control a pencil-beam, limited-scan phased array radar used in a multiple-target tracking application. The system design consists of a mechanically steered radar employing an agile electronically scanned aperture with the attendant grating lobes. The selected design can be executed in real time by the system data processor in parallel with operating and controlling other aspects of the system. The suboptimal design utilizes a lookup table approach to selecting filter gains as a function of state vector, turret motor status, and turret dynamic lag. These gains are derived to achieve a balance between required transmit and receive beam steer accuracy and ability to follow turret dynamics during the accelerations with minimum lag