The BRADLEY DEPARTMENT of ELECTRICAL and COMPUTER ENGINEERING

Antennas & Propagation Research | ECE | Virginia Tech

Research Areas

Whether developing new antennas or studying phenomena in space with radio telescopes, ECE researchers are pushing the boundaries of existing technologies. They are creating antennas that can transfer data more efficiently and accurately, and developing and improving radio telescopes to capture radio signals in space.

Associated Labs & Facilities

Current Research

Antenna Miniaturization

Time-variant and nonlinear techniques are employed to radiate a wideband signal using electrically small antennas. Different methodologies have been introduced and tested for FSK and QPSK modulation. Electrically small and extremely small antennas can be used in implanted wireless devices in addition to wireless power transfer for implanted devices. Another application includes SLF and VLF radios used in mines and submarines.

Radio Frequency Identification

The Virginia Tech antenna group is investigating various types of Radio Frequency Identification (RFID) tags and readers--including passive, active, and chipless RFIDS. The team is among the pioneers in the area of chipless RFID. Their efforts have resulted in advanced space-time-frequency detection and localization techniques that can be used for a wide range of applications, including "through the wall" and cancer tumor detection.

Long Wavelength Array 1

LWA1 (Long Wavelength Array Station 1) is a compact array radio telescope operating in the 10--88 MHz band, co-located with the VLA in central New Mexico. LWA1 currently consists of 256 dual-polarization active dipole antennas in a 100 m x 110 m elliptical footprint, plus five additional "outrigger" dual-polarization active dipole antennas on 150--500 m baselines. Each dipole is individually digitized and then formed into four beams using a delay-and-sum technique. The beams can be pointed independently; thus in some sense LWA1 is actually four radio telescopes. It is also possible to record the individual dipole signals. LWA1 science includes pulsars, astrophysical transients, the Sun, Jupiter, the ionosphere, and more. LWA1 is jointly operated by the University of New Mexico and Virginia Tech, with participation from the U.S. Naval Research Lab.

Very Large Array

ECE researchers working with the National Radio Astronomy Observatory (NRAO) have successfully demonstrated a new antenna feed system for the Very Large Array (VLA). The new feed system allows the VLA to observe continuously from 54--85 MHz, replacing a previous system with much narrower bandwidth, and which was only intermittently installed due to interference with the VLA's higher-frequency systems. The new system avoids the interference problem by using four dipole-like elements lying outside the signal path used by the higher-frequency systems, and combining them to create signals equivalent to those from dipoles located in the nominal, but interfering, locations. The increased bandwidth is obtained by replacing the dipoles with a novel antenna element purpose-built for this application.