IEEE SENSORS JOURNAL, VOL. 14, NO. 8, AUGUST 2014
Guest Editorial Special Issue on Antenna Design and Integration in Smart Sensors
NTENNAS are key components in wireless sensors and sensor networks. Efficient, low loss, compact antennas are essential for such networks. The integration of the antenna in the sensor and the in-situ operation of the antenna in the sensor’s environment are important practical considerations in the design of the antenna. Low loss is especially important for sensors operating in locations that are difficult to access as the antenna may form part of a wireless power transfer system to recharge the sensor battery. The papers in this Special Issue are divided into three groups: papers presenting general antennas for sensors, application-oriented papers, and integration technology papers. A review of printed antennas for sensors, presented in the first paper, describes their desirable features of light weight, low profile and ease of integration in systems. Advances in conducting ink and high-resolution printing make possible low-cost production of planar and conformal, specialshaped antennas for sensors. This leads to RFID-based sensors, which are reviewed in the second paper. The emphasis is on zero-power wireless sensors. Improving the link reliability using polarization diversity is the subject of the next paper. The link in question is confined to an enclosed environment where the signal is subject to harsh fading conditions. A design methodology is presented in the next paper for planar circular spiral conductors that are used to form a passive wireless implantable pressure sensor. The design has a small form factor for minimally invasive implantation. The application-oriented papers start with sensors for deep tissue characterization in bodies. A wrap-around sensor uses an array of antenna elements at low frequency and detects scattering parameters that are used to evaluate the permittivity of tissues that may indicate abnormalities. The second application considered is in target detection using antennas fabricated on a silicon MEMS platform. This paper discusses the limitations of silicon as a hinge material, but demonstrates operation over a wide band of 10-16 GHz. In a similar application, the next paper adds range detection to angle determination by using a frequency diverse array. This is done using a non-uniform array for transmission and a uniform phased array for reception. The cooperative transmit-receive beam-forming produces the range-angle imaging. There are two papers on integration and both use 90-nm CMOS technology. The first paper presents a planar antenna that is integrated with a system-on-a-chip for ultrawideband
pulse radar for medical applications. Tests show detection of the respiratory rate of people at distances up to 45 cm from the radar sensor. The second paper addresses a sub-THz array with embedded signal processing. A planar antenna array is integrated with 12 silicon field effect plasma wave detectors. An application example of multiwavelength transmission imaging is given. The collection of papers in this Special Issue illustrates the critical functions that antennas play in wireless sensors and sensor networks, while just touching on part of the topic of antennas in sensors. There exists many opportunities for new designs and new applications. With the spread of wireless sensors everywhere in our world, with implementations in health and environmental monitoring, smart buildings and infrastructure, as well as the Internet of Things for example, the potential for innovation in sensor system design using advanced antennas is unlimited.
A MIR I. Z AGHLOUL, Guest Editor Sensors and Electron Devices Directorate (SEDD) U.S. Army Research Laboratory Adelphi, MD 20783 USA Virginia Tech Department of Electrical and Computer Engineering Blacksburg, VA 24061 USA [email protected]
; [email protected]
T REVOR S. B IRD, Guest Editor Department of Engineering Macquarie University Sydney NSW 2109, Australia [email protected]
J ENNIFER T. B ERNHARD, Guest Editor Department of Electrical and Computer Engineering University of Illinois at Urbana–Champaign Urbana, IL 61801 USA [email protected]
Digital Object Identifier 10.1109/JSEN.2014.2333571 1530-437X © 2014 IEEE. Personal use is permitted, but republication/redistribution requires IEEE permission. See http://www.ieee.org/publications_standards/publications/rights/index.html for more information.