Joongsuk Park

An ultrawide-band microwave radar sensor for nondestructive evaluation of pavement subsurface

A new ultrawide-band (UWB) microwave radar sensor operating from 0.6 to 5.6 GHz has been developed using microwave integrated circuits for pavement subsurface characterization. UWB antennas operating from 0.5-10-GHz have been designed and tested for use in the sensor. A new simple, yet effective, accurate procedure was also developed to compensate for the common amplitude deviations and nonlinear phase errors produced by the inherent imperfection of the system. The developed compensation method is applicable to other systems and effectively reduces the potential masking of adjacent targets as well as facilitating and increasing the accuracy for target identification of the sensor. The sensor has been used to assess a pavement sample with less than 0.1 in of error in the pavements layer thickness. The developed system represents the first UWB stepped-frequency radar sensor completely realized using microwave integrated circuits over the frequency range of 0.6-5.6 GHz for subsurface sensing applications.

Stepped-Frequency Radar Sensor Analysis

The analysis of SFCW radar sensors is presented in this chapter. Specifically, it addresses the system’s important parameters including transmitted and received signals, down-converted I and Q signals, synthetic pulse, angle and range resolutions, frequency step, number of frequency steps, total bandwidth, range or penetration depth, range accuracy, range ambiguity, pulse repetition interval, dynamic range, and system performance factor. Maximum ranges or penetration depths in sensing multi-layer and buried targets are also discussed. The presented materials, although concise, should provide sufficient information for RF engineers to undertake the analysis of their own SFCW radar sensors and help design these sensors for sensing applications.

A Ka-band stepped-frequency radar sensor for surface and subsurface sensing

A new millimeter-wave radar sensor employing stepped-frequency radar technique has been developed using microwave and millimeter-wave integrated circuits and demonstrated for surface and subsurface sensing. The sensor is based on the coherent super-heterodyne scheme and operated from 29.72-37.7 GHz. It has been used to profile the surface of a sample with range accuracy within plusmn0.1 cm. The sensor was also used to monitor continuously varying liquid level in a tank and was able to detect the displacement of liquid level with less than plusmn 0.1 cm error. The sensor successfully detected and located anti-personnel mines buried under sand with less than 1.8 and 0.2 cm of errors in horizontal and vertical directions, respectively.

Development of Stepped-Frequency Continuous-Wave Radar Sensors

This chapter presents the development of two SFCW radar sensors realized in single packages with microwave integrated circuits (MICs) and microwave monolithic integrated circuits (MMICs): a millimeter-wave sensor operating across 29.72-37.7 GHz and a microwave sensor working from 0.6-5.6 GHz. The designs of the transceivers, antennas and signal processing, which form the most important parts of the sensors, are described. The presented information, although concise, is essential and in sufficient details, which enable microwave engineers to build similar microwave and millimeter-wave SFCW radar sensors for various sensing applications.

Characterizations and Tests of Stepped-Frequency Continuous-Wave Radar Sensors

This chapter discusses the electrical tests and several sensing measurements of the developed microwave and millimeter-wave SFCW radar sensors described in Chap. 4. The electrical tests verify the electrical performances of these systems to make sure they possess the desired electrical characteristics as designed. These electrical tests, while do not directly show the actual performance of the sensors in practical sensing applications, are essential in system development and need to be conducted first. The sensing measurements of the millimeter-wave SFCW radar sensor described in this chapter include surface profiling, liquid-level measurement, and detection and location of buried objects. The sensing measurements for the microwave SFCW radar sensor are the measurements of pavement structures including an actual pavement in laboratory and actual roads. The measured sensing results show good agreement with the actual values, demonstrating the workability and usefulness of the developed sensors for various surface and subsurface sensing applications. Moreover, this chapter also describes of the procedures involved in the sensing measurements, which provide not only the operations of these sensors, but also their system evaluations for sensing applications.

General Analysis of Radar Sensors

This chapter addresses the general analysis of radar sensors. Specifically, it discusses signal propagation in media encountered in using radar sensors, signal scattering from objects, systems equations including Friis transmission equation and radar equations, signal-to-noise ratio, receiver sensitivity, maximum range or penetration depth, and system performance factor. Understanding these basic parameters provides general insight of a radar sensor’s possible performance and operation and allows its general analysis to be conducted, which are essential toward the design of microwave systems for sensing applications.

An 18ms-latency wireless high quality codec SoC for full HD streaming

An SoC integrating both an IEEE 802.11n Wireless LAN (WLAN) and a high quality codec is implemented using 90nm CMOS technology for wireless connectivity between full HD video-supporting devices. The WLAN operates with up to 270-Mbps data rates using 2×3 MIMO technologies and the codec supports up to 1080P 60Hz resolution with 30-bit RGB color format. The system achieves total 18ms latency, which enables this SoC to be used in gaming consoles and PCs as well as full-HD digital TVs with 1.5W power consumption.