On Use of Range Rate Information in Target Tracking under Dense Clutter Background in Airborne Radars

By : Narasimhan RS , TV Prakash Rao

Page No: 185-215

Abstract: 
Data association techniques in radar target tracking problem play an important role in tracking targets of interest with high accuracy during both target non-maneuvering and maneuvering phases in a multiple target scenario. The data association problem further gets complicated due to the presence of detections from clutter leaks and false alarms in addition to detections from targets of interest. These techniques have to cater for uncertainty in the origin of measurement and low to moderate probability of detection of targets of interest. In this paper, we propose to utilize range rate information extensively to reduce plot to track miss-correlation, detect target maneuvers early, estimate target manoeuver intensity and choose optimum revisit rate as well as waveform to maximize target visibility. Tracking range rate is essential to exploit this information in tracking functions. This poses a problem due to its highly nonlinear relation to Cartesian target states. Use of nonlinear tracking filters have been shown to suffer from stability issues in addition to being sub-optimum. In this paper, we propose to decouple the tracking of range rate and position by using two parallel Interacting Multiple Model (IMM) filters. The range rate filter consists of four models in IMM framework to track range and range rate of targets in non-maneuvering and maneuvering phases. Since range rate is highly sensitive to target kinematic changes, a reliable and early maneuver detection is possible in range rate dimension and this is exploited in the design of tracking filter. We propose an efficient maneuver tracking algorithm using the electronic beam steering feature of phased array radars to detect and track evasive target maneuvers. In addition, the range rate filter is used to estimate the maneuver intensity and choose optimum update rate for tracking. Finally, the maneuver tracking performance of position tracking filter is improved by adapting mode transition probability matrix. We establish the performance of range rate and position tracking filters for non-maneuvering and maneuvering targets through simulations.

Authors :
Narasimhan RS
Scientist F, LRDE, DRDO, CV Raman Nagar, Bengaluru-560093.

TV Prakash Rao
Member, Institute of Defence Scientists and Technologists, Defence Research and Development Organisation [DRDO], Bengaluru-560075.
 

DOI: https://doi.org/10.32381/JCISS.2019.44.1-4.11