A Tutorial on the Sequential Sampling Impulse Radar Concept and Selected Applications

Abstract

The sequential sampling impulse radar is a radar concept that has been known for a very long time. Ultrawideband (UWB) radar systems have been realized based on this concept long before the popular phrases UWB and UWB radar were created. Its hardware simplicity, low cost, potentially high bandwidth and high range resolution, as well as the unsurpassed low power consumption of some of its variants have made it one of the most widely used radar concepts in industrial automation today. Despite its widespread use in practice, however, there are only few publications, textbooks and tutorials that describe this concept in detail and all its varieties and aspects. Especially, the correlation properties and the resulting signal-to-noise ratio (SNR), as well as the phase injection locking of pulsed oscillators, that is required for power-efficient options, have rarely been described in detail. This tutorial introduces the typical sequential sampling impulse radar concept step by step and presents the characteristics and pros and cons. As for the correlation properties and the SNR, the concepts are compared to those of standard coherent impulse radar systems and of frequency modulated continuous wave (FMCW) radar. In addition to the system theory, selected applications are presented to illustrate the attractiveness and elegance, but also the limits, of this interesting and important radar concept. The shown applications range from those in the main field of use of this type of radar, that is, industrial automation, to former and current radar concepts in the areas of automotive radar, ground penetrating radar (GPR), security scanners, and biomedical radar systems.

Keywords

• Automotive radar
• correlation receiver
• ground penetrating radar
• impulse radar
• MTT 70th Anniversary Special Issue
• level radar