The analysis in this book, so far, has concentrated on using sensors to detect the presence of targets in noise and clutter. However, sensors are capable of much more than that. Consecutive measurements of a target's position (and sometimes velocity) can be used to calculate the target state (position, velocity, and acceleration), from which a good estimate of the future position can be made. This process of estimation is generally referred to as tracking. For most time-of-flight sensors that operate in polar space, this involves following the target independently in both range and angles to obtain good estimates of its position in three dimensions. This chapter is concerned with the mechanics of the tracking process.

Chapter Contents:

• 13.1 Introduction
• 13.2 Range Estimation and Tracking
• 13.2.1 Range Gating
• 13.3 Principles of a Split-Gate Tracker
• 13.3.1 Range Transfer Function
• 13.3.2 Noise on Split-Gate Trackers
• 13.4 Range Tracking Loop Implementation
• 13.4.1 The a-β Filter
• 13.4.2 The Kalman Filter
• 13.4.3 Other Tracking Filters
• 13.5 Ultrasonic Range Tracker Example
• 13.6 Tracking Noise after Filtering
• 13.7 Tracking Lag for an Accelerating Target
• 13.8 Worked Example: Range Tracker Bandwidth Optimization
• 13.9 Range Tracking Systems
• 13.9.1 Lidar Speed Trap
• 13.10 Seduction Jamming
• 13.11 Angle Measurement
• 13.11.1 Amplitude Thresholding
• 13.11.2 Proximity Detector Example
• 13.12 Angle Tracking Principles
• 13.12.1 Scanning Across the Target
• 13.12.2 Null Steering
• 13.13 Lobe Switching (Sequential Lobing)
• 13.13.1 Main Disadvantages of Lobe Switching
• 13.14 Conical Scan
• 13.14.1 The Squint Angle Optimization Process
• 13.14.2 Measuring the Conscan Antenna Transfer Function
• 13.14.3 Application
• 13.14.4 Main Disadvantages
• 13.14.5 Other considerations
• 13.15 Infrared Target Trackers
• 13.16 Amplitude Comparison Monopulse
• 13.16.1 Antenna Patterns
• 13.16.2 Generation of Error Signals
• 13.17 Comparison between Conscan and Monopulse
• 13.18 Angle Tracking Loops
• 13.19 Angle Estimation and Tracking Applications
• 13.19.1 Instrument Landing System (ILS)
• 13.19.1.1 Localizer Transmitter
• 13.19.1.2 Localizer Receiver
• 13.19.1.3 Glide Slope Equipment
• 13.20 Worked Example: Combined Acoustic and Infrared Tracker
• 13.20.1 Operational Principles of Prototype
• 13.20.2 Theoretical Performance
• 13.20.3 Tracker Implementation
• 13.20.3.1 Beacon
• 13.20.3.2 Receiver
• 13.20.4 Construction
• 13.20.5 Control Algorithms
• 13.21 Angle Track Jamming
• 13.22 Triangulation
• 13.22.1 Loran-C
• 13.22.1.1 Summary of Operation
• 13.22.1.2 Measurement Process
• 13.22.1.3 Advantages of Loran-C
• 13.23 References

Inspec keywords: radar tracking; target tracking; radar clutter

Other keywords: clutter; angle estimation; noise target; angle tracking; time-of-flight sensors; target position; range estimation; polar space; range tracking

Subjects: Radar equipment, systems and applications; Signal processing and detection