This paper examines the probability that any millimeter-wave radar systems will interfere mutually by considering spatial, temporal, and operational frequency-related overlaps. It examines the nature and magnitude of the interference under different conditions and for different sensor types before concluding that in an overlapping frequency band, the probability that interference will occur is high. It goes on to demonstrate that, though there are some forms of interference that can be identified and controlled, there are others which are impossible to isolate, resulting in degraded target detection performance and tracking

The analysis presented in this article shows that the Great Seal bug has a well-coupled eigenmode around 1800 MHz, which is consistent with some of the references. This was probably one of the harmonics of the illumination source, as a high transmit power at the lower frequency would have been easier to generate. In addition, the interaction between acoustically introduced vibrations of the diaphragm would generate an AM signal that could be detected remotely.

This is a comprehensive textbook and reference that provides a solid background in active sensing technology. Beginning with a historical overview and an introductory section on signal generation, filtering and modulation, it follows with a section on radiometry (infrared and microwave) as a background to the active sensing process. The core of the book is concerned with active sensing, starting with the basics of time-of-flight sensors (operational principles, components), and goes through the derivation of the radar range equation, and the detection of echo signals, both fundamental to the understanding of radar, sonar and lidar imaging. Several chapters cover signal propagation of both electromagnetic and acoustic energy, target characteristics, stealth and clutter. The remainder of the book involves the basics of the range measurement process, active imaging with an emphasis on noise and linear frequency modulation techniques, Doppler processing, and target tracking.

Entomologists need to observe and monitor insects in their natural habitats for various reasons. One of the most common techniques in use today is to attach low-cost harmonic sensor or transponder to insects and to track them using an associated harmonic radar. Existing harmonic transponders based on monopoles, loop-dipoles, and Minkowski loops have been successfully attached to small low-flying insects. However, they offer significant constraints from a mounting perspective, weight and size considerations, aerodynamic drag, and the elevation of the insect center of gravity. This paper addresses these issues by presenting novel design methodologies for millimeter wave harmonic sensors and radar. The sensors address the challenges of ease of design and fabrication, robustness, conversion efficiency, miniaturization, antenna entangling, and attachment problems that are generally encountered with other transponders.