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December 2008 Reflectarray Cells Operate Beyond 100 GHz RECENTLY, IT WAS PROVEN that the phase of signals in the microwave and millimeter-wave bands can be modulated by exploiting the physical response of liquid-crystal molecules to an applied electric field. Several prototype devices have emerged that are based on liquid-crystal substrates with tunable permittivity. For example, prototype reflectarray structures that operate at frequencies above 100 GHz have been designed by Wenfei Hu, Robert Cahill,... — Nancy Friedrich November 2008 Body-Area Network Monitors Emotional Reactions LEUVEN, BELGIUM—A new research concept uses a combination of body parameters to monitor a person’s arousal level. IMEC has developed an ambulatory arousal monitor in a compact form factor with a long battery lifetime. It consumes less power than a comparable Bluetooth device. In fact, the entire system allows several days of autonomy on a commercial prismatic Li-Ion battery. IMEC’s approach within its Human++ program at Holst Centre uses a body-area network... — Dawn Hightower November 2008 TriQuint-Powered Integrated Circuits Used In “Big Bang” Experiment HILLSBORO, OR- TriQuint Semiconductor, Inc.’s technology was leveraged in the design of integrated circuits (ICs) that will be used in the CERN Large Hadron Collider (LHC). Billed by some as the “world’s biggest, most highly anticipated physics experiment,” the LHC is a 27-km (17-mile)-long particle accelerator. It was designed by the European Center for Nuclear Research (CERN) to help physicists recreate the conditions that occurred just after the Big... — Dawn Hightower October 2008 Antenna Solution Ends Hearing-Aid Buzzing When Cellular phones and hearing aids interact, many hearing-aid users experience a severe buzzing noise. By reducing the near-field electromagnetic energy around a cellular phone — Nancy Friedrich August 2008 X-Band Oscillator Antenna Targets Phased-Array Systems Active integrated antennas (AIAs) with one or more active devices and circuits within the radiating element have been garnering quite a bit of attention. They promise to deliver advantages like compact size, low cost, and adaptability to phased-array-antenna systems. Recently, an AIA element was successfully fabricated on a high-dielectric-constant ({? r} = 10.2) microwave laminate that is 0.635 mm thick. The development hails from Carl H. Mueller, Carol... — Nancy Friedrich August 2008 60-GHz Receiver May Be Realized In CMOS Wireless communications systems like highspeed personal-area networks and real-time video transmission demand performance that is above the Gigabit-per-second range. As a result, such systems may require the bandwidth provided by a 60-GHz millimeter-wave transceiver. The traditional approach behind such a transceiver is to leverage compoundsemiconductor monolithic microwave integrated circuits (MMICs). Yet, that 60-GHz transceiver may potentially be realized in... — Nancy Friedrich August 2008 Three-Branch Antenna Serves GPS, UMTS, And ISM Bands Mobile-phone antennas must become increasingly multiband in order to accomplish their many functions. In response to these trends, researchers have proposed a design method that provides quarter-band operation for the following bands: GPS (1565 to 1585 GHz), UMTS/W-CDMA (1920 to 2170 MHz), Industrial Scientific Medical (ISM; 2400 to 2483.5 MHz), and SDMB (2630 to 2655 MHz). This work is credited to Byung-chan Jang, Che-young Kim, and Jeung-keun Park from the... — Nancy Friedrich July 2008 Planar Folded Dipole Antenna Achieves Wideband Performance WIDEBAND WIRELESS SYSTEMS like Ultra Wideband (UWB) require antennas that are wideband and compact. One solution is a dipole antenna with folded elements, which is constructed by folding both ends of a folded dipole antenna to widen the antenna’s bandwidth. Research into a simplified configuration has been performed in Kanagawa, Japan by Shingo Tanaka, Satoru Horiuchi, Yasunori Atsumi, and Yoichi Ido from Yazaki Corp.’s Microwave Technology ... — Nancy Friedrich July 2008 24-Gb/s Software-Controlled Transmitter Outperforms Baseband Systems RECENTLY, A STUDY REVEALED a large gap between the fundamental limits of signaling (Shannon capacity) and the limits that are achievable with baseband signaling. In some applications, notches in the frequency domain are part of the link channels’ frequency response. Multitone (MT) signaling may then be employed to potentially reduce the gap between current link performance and Shannon capacity. Unfortunately, conventional MT techniques are not... — Nancy Friedrich July 2008 On-Chip Slot Antennas Prove CMOS Approach ON-CHIP ANTENNAS can be used in applications from radio-frequency-identification (RFID) tags to RF sensors/radars. Gallium arsenide (GaAs) has been the most commonly used substrate in many of these applications. Yet active RF devices are expected to increasingly turn to silicon for its low cost, high integration and other advantages. Many researchers have sought to fabricate antennas on a silicon substrate. At China’s Shanghai Jiao Tong University,... — Nancy Friedrich June 2008 Dielectric-Resonator Antenna Serves As Filter THE TREND TOWARD BUNDLING multiple components into a single module for wireless communications has researchers eying a dual-function DRA that can simultaneously act as the antenna and packaging cover. The problem is that the DRA’s quality (Q) factor tends to be low to enhance both radiation and bandwidth. In contrast, the Q-factor of the dielectric-resonator filter (DRF) is usually high to reduce insertion loss. It is therefore contradictory to... — Nancy Friedrich June 2008 Microwave Approach Detects Lymphatic Disease LYMPHATIC FILARIASIS (LF) is a parasitic infection spread by mosquitoes. This disabling and disfiguring disease is caused by thread-like parasitic worms. To accomplish the earlier detection of LF, a microwave method has been presented by Anil Lonappan, Vinu Thomas, G. Bindu, Joe Jacob, and K.T. Mathew from the Department of Electronics, Microwave Tomography, and Materials Research Laboratory at India’s Cochin University of Science and Technology... — Nancy Friedrich June 2008 Define Lightwave Antennas For Measurement Systems COMPARED TO MICROWAVE ANTENNAS, lightwave antennas have different measurement characteristics because of their use of shorter wavelengths. This aspect makes it difficult to design lightwave antennas according to each application system. A technique for measuring the far-field radiation pattern (FFP), gain, and transmissivity of each portion of an aperture has been described by Yasushi Munemasa, Tadashi Takano, and Makoto Mita from Tokyo University... — Nancy Friedrich May 2008 Electrically Tune A Planar Inverted-F Antenna WITH THE PLETHORA of wireless standards being applied to today’s handheld devices, the antennas integrated in those products must often operate in 10 or more frequency bands. For the antenna designer, this translates into the challenge of having to cover a single very wide frequency band or multiple frequency bands while maintaining small size and high efficiency. A novel solution may be to use antennas that have a reconfigurable operating frequency with... — Nancy Friedrich May 2008 Dielectric Blood Measurement Detects HIV/AIDS DESPITE THE FACT THAT HIV/AIDS has grown into a worldwide pandemic, Elisa and Western Blot tests are still the only tests available for detecting it. Yet a new testing method could be based on the measurement of the dielectric properties of blood at microwave frequencies. Behind this proposed method are the efforts of C. Rajasekaran from the Department of Medicine at Medical College (Kerala, India) together with Anil Lonappan, Vinu Thomas, G. Bindu, Joe Jacob,... — Nancy Friedrich May 6, 2008 RFID Tags Take A Space Trip To Test Durability Laser coding and printing specialist DataLase along with US company Intermec and NASA have collaborated in the launch of a selection of marked RFID tags and aluminium discs into space... — Paul Whytock May 6, 2008 Wireless Brain Monitoring System Is Powered By Patient’s Body Heat Independent research centre, IMEC, has developed a battery-free wireless 2-channel EEG (electroencephalography or brain wave monitoring system) powered by a hybrid power supply using body heat and ambient light... — Paul Whytock April 2008 Constraints Impact UWB Antenna Performance Solutions for Optimal Waveforms for an Ultra-Wideband (UWB) link have been presented using transmit and receive antennas that are realistic and specific. Yet antenna expert David M. Pozar, who hails from the Department of Electrical and Computer Engineering at the University of Massachusetts (Amherst, MA), asserts that a better approach might be to determine the best performance that can be obtained for any antenna with certain constraints, such as... — Nancy Friedrich April 2008 UHF CPUs Promise To Secure RFID Communications To Attach to Merchandise Ranging from books to fresh foods, radio-frequency identification (RFID) tags need physical flexibility. RFID RF integrated circuits (RFICs) also must be produced at extremely low cost. In addition, they have to be able to provide secure communication. To meet these demands, a 13.56-MHz RF central-processing unit (CPU) with a flexible and a glass substrate was proposed by Hiroyuki Takashina and Yoshinari Yamashita from TDK... — Nancy Friedrich March Rectifier Circuit Powers Sensor Network Tags At 950 MHz In 1996, R.S. Dixon of Ohio state University proposed a new concept for a radio telescope array dubbed “Argus.” This approach used a large array of broadband antennas with broad beamwidth that provides all-sky field of view (FOV), can generate multiple simultaneous beams, and performs “retroactive observing.” The design of Argus, its theoretical performance, the system’s ability to detect and localize the sun, and various capabilities were recently... — Nancy Friedrich  prev. page
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