2. RF Imaging using mmWave Sensors

Introduction

Electromagnetic radiation in the range of wavelengths from 1 cm to 1 mm is characterized as millimeter-wave (MMW) radiation. One of the modem trends in radar technology development is moving of operating frequencies to millimeter wave part of spectrum. [1] notes the advantages of such high frequencies: such as compact system size, high spatial and better target resolution. There are two most common forms of mm-wave imaging: Passive MM-Wave Imaging, Active Radar Imaging. Active scanners direct millimeter wave energy at the subject and then interpret the reflected energy. Passive systems create images using only ambient radiation and radiation emitted from the human body or objects.

Implementation

We propose to use the mmWave by Texas Instruments, IWR1642 for RF Imaging. The IWR1642 device is as a highly integrated 76–81-GHz radar-on-chip solution for short-range radars. The device comprises the entire millimeter wave (mmWave) radio-frequency (RF) and analog baseband signal chain for two transmitters (TX) and four receivers (RX), as well as two customer-programmable processor cores in the form of a C674x digital signal processor (DSP) and an ARM® Cortex®-R4F microcontroller (MCU). (Reference: White paper- IWR1642 mmWave sensor: 76–81-GHz radar-on-chip for short-range radar applications)

mmWave

Literature Survey

The current radar hardware and computational methods are developed for mainstream radar applications, such as air and terrestrial traffic control, marine radar remote sensing, outer space surveillance [3]. In recent years, there has been a certain amount of research interest in the design of next-generation radar systems for applications such as gesture recognition (e.g., implemented on handhelds, laptops or televisions), surveillance and vehicular situational awareness. [3] presents Soli, a new, robust, high-resolution, low-power, miniature gesture sensing technology for human-computer interaction based on millimeter-wave radar. [4] illustrates the use of mmWave sensors to detect non metallic objects like ceramic knifes as well as metallic objects hidden under clothes. [5] demonstrates a passive millimeter-wave imaging concept based on a folded Schmidt camera which has been developed and applied to poor weather navigation and security .