About

Jennifer Bernhard is the Department Head of Electrical and Computer Engineering at the University of Illinois Urbana-Champaign and holds the title of Donald Biggar Willett Professor in Electrical and Computer Engineering. She earned her Ph.D. in Electrical Engineering from Duke University in 1994. Her research addresses applications-oriented electromagnetic problems with an emphasis on theoretical analysis and experimental investigation. Her research group focuses on two main areas: Electromagnetics for Wireless Communication and Reconfigurable Active and Passive Antennas. In the area of wireless communication, her work centers on developing and designing technology that enables high data-rate wireless communication and parallel computation. Her group investigates the effects of packaging on antenna performance and develops models for internal antennas, embedded antennas, and diversity schemes, including synthesis approaches for internal portable antenna systems such as IoT devices. Her research on reconfigurable antennas involves implementing reconfigurability using MEMS, microwave switches, ferroelectric materials, or mechanical actuation to provide flexibility in operating frequency, bandwidth, and radiation pattern. These innovations aim to reduce the size, cost, and weight of antenna systems, improve efficiency, and enhance system performance. Prof. Bernhard's work is supported by advanced fabrication facilities, an anechoic chamber, and collaboration opportunities with the UIUC Center for Computational Electromagnetics. She has received numerous honors, including the NSF CAREER Award, IEEE Fellow, and various teaching and leadership awards. Her contributions extend to professional service, including leadership roles in IEEE and advisory groups, and she has been recognized for her excellence in teaching and research.

Research topics

• Computer science
• Electronic engineering
• Acoustics
• Electrical engineering
• Materials science

Selected publications

• Mutual-Coupling-Matrix-Based Approach to Improve Modal Purity in Orbital Angular Momentum Links

  2025-07-13

  articleSenior author

  Orbital angular momentum (OAM) has gained attention as a multiplexing technique due to the spatial orthogonality between different OAM modes at any given frequency. Despite their higher spectral efficiency, OAM links suffer from important limitations such as susceptibility to angular misalignment and poor multipath performance. Moreover, coupling between opposing elements in OAM-generating uniform circular arrays (UCAs) introduces radiation pattern ripples (H. Chireix, “Antennes à rayonnement zénithal réduit,” L'Onde Electrique, vol. 15, 1936), which degrade OAM modal purity. Although various antenna structures have been used to reduce coupling, this often results in larger arrays that may still suffer from reduced modal purity (G. A. Muniz-Negron and J. T. Bernhard, “Orbital angular momentum from an antenna engineer's perspective,” 2024 Antenna Applications Symposium, 2024).

  PublisherDOI

• Generalized Antenna Scattering Matrix for Simulation of Antenna Systems with Nonlinear and Time-Varying Components

  2025-07-13

  articleSenior author

  Typical scattering matrices for antennas only capture the port behavior of an antenna. This is adequate for many applications, but the radiating and scattering behavior of the antenna is lost. The generalized antenna scattering matrix corrects this by describing the coupling between guided waves at the ports and spherical waves in the far field. The generalized antenna scattering matrix is given by

  PublisherDOI

• Seed Funding Opportunities and Challenges

  2024-02-08

  articleOpen access1st authorCorresponding
  PublisherOA PDFDOI

• NON-RECIPROCAL ANTENNA RADIATION ENABLED BY TRUE TIME DELAY

  2024-09-01

  reportOpen access

  In general, these approaches suffer from high losses and/or

  PublisherOA PDFDOI

• Investigation of Curvature Radius on the Performance of a Reconfigurable Microstrip Parasitic Array (RMPA)

  2024-10-15

  articleSenior author

  This work studies the effects of curvature on a pattern reconfigurable microstrip parasitic array (RMPA). Varying the effective electrical length of the parasitic elements allows for switching or scanning the beam pattern. The RMPA is simulated on a singly curved surface and oriented to scan along elevation. The resonant frequency of the structure is observed to decrease with the radius of curvature. Additionally, beam tilting behavior significantly deteriorates relative to the planar design. Several design parameters are investigated for the purpose of correcting beam tilting performance, including substrate width and parasitic element length and spacing. As the curvature radius decreases, simulations indicate that smaller element spacing improves the directivity of the beam at higher frequencies.

  PublisherDOI

• Frequency Behavior of a Resonant Shielded Loop With a Variable Gap Position

  2024-12-01 · 1 citations

  articleSenior author

  Size and bandwidth are among the most common tradeoffs in antenna design. Electrically small antennas (ESAs) suffer from low radiation resistance, high reactance, and typically narrow bandwidths. Resonant antennas offer a higher radiation resistance lower and input reactance than ESAs at the cost of a larger footprint. Shielded loops offer a compromise between bandwidth and size. We observed that S<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11</inf> is minimum when the electrical length between the gap and the short from inner to outer conductor is λ/4. The frequency behavior depends on this gap position rather than the overall loop radius.

  PublisherDOI

• Reconfigurable Antennas

  Encyclopedia of RF and Microwave Engineering · 2024-12-01 · 2 citations

  other1st authorCorresponding

  Abstract High‐speed wireless systems continue to require more functionalities from antennas than can be provided by classic designs. One approach to this challenge is to develop and implement reconfigurable antennas. The goal of a reconfigurable antenna—one that can adjust its operating frequency, bandwidth, and/or radiation pattern to accommodate changing system requirements—poses significant challenges to both antenna and systems designers. This chapter first defines antenna reconfigurability, provides insight into early related historical developments, and then highlights some of the more recent advances in the area of antenna reconfiguration. Additionally, some of the barriers that still need to be overcome to arrive at realizable, fieldable technologies are discussed. These barriers include the development of reliable, cost‐effective, and mass‐manufacturable switching and tuning elements, the design of bias networks that will not interfere with antenna operation, and the continued expansion of signal processing and feedback algorithms to fully exploit this new antenna functionality.

  PublisherDOI

• Effects of Interelement Spacing on the Input Impedance of Uniform Circular Arrays for Orbital Angular Momentum (OAM) Generation

  2024-12-01

  articleSenior author

  Orbital angular momentum (OAM) has gained popularity as a multiplexing technique. However, little emphasis has been given to the network parameters of OAM generating antennas. In this paper, we calculate the input impedance of OAM-generating uniform circular arrays (UCA) of varying radius and monopole height using 4NEC2. For tightly coupled arrays, we observed that the elements’ input impedance varies significantly as a function of both monopole height and array radius. Our simulation results can be used for future designs that consider resonant, rather than electrically small, elements for improved gain and power efficiency.

  PublisherDOI

• Reconfigurable Antennas

  Encyclopedia of RF and Microwave Engineering · 2024-12-16

  other1st authorCorresponding

  Abstract High‐speed wireless systems continue to require more functionalities from antennas than can be provided by classic designs. One approach to this challenge is to develop and implement reconfigurable antennas. The goal of a reconfigurable antenna—one that can adjust its operating frequency, bandwidth, and/or radiation pattern to accommodate changing system requirements—poses significant challenges to both antenna and systems designers. This chapter first defines antenna reconfigurability, provides insight into early related historical developments, and then highlights some of the more recent advances in the area of antenna reconfiguration. Additionally, some of the barriers that still need to be overcome to arrive at realizable, fieldable technologies are discussed. These barriers include the development of reliable, cost‐effective, and mass‐manufacturable switching and tuning elements, the design of bias networks that will not interfere with antenna operation, and the continued expansion of signal processing and feedback algorithms to fully exploit this new antenna functionality.

  PublisherDOI

• Building Leadership Opportunities

  2024-02-06

  articleOpen access1st authorCorresponding
  PublisherOA PDFDOI

Recent grants

• Collaborative Research: Enabling Technology for MIMO Systems on Mobile Devices: Antennas, Switches, and Packaging

  NSF · $190k · 2005–2009

Frequent coauthors

• Thomas Siegert

  University of West Florida

  287 shared

• Geographic Activities

  Engineering Systems (United States)

  286 shared

• Karen Hawkins

  Xi'an Jiaotong University

  282 shared

• Cherif Amirat

  Institute of Electrical and Electronics Engineers

  282 shared

• Cecelia Jankowski

  Institute of Electrical and Electronics Engineers

  282 shared

• Stephen Welby

  Institute of Electrical and Electronics Engineers

  278 shared

• Renuka Jindal

  Canadian Standards Association

  266 shared

• Vijay K. Bhargava

  University of British Columbia

  266 shared

Education

• Ph.D., Electrical Engineering

  Duke University

  1994

• M.S., Electrical Engineering

  Duke University

  1990

• B.S.E.E., Electrical Engineering

  Cornell University

  1988

Awards & honors

• National Science Foundation CAREER Award (2000)
• H. A. Wheeler Applications Prize Paper Award, IEEE Antennas…
• IEEE Fellow (2010)
• College Award for Leadership or Institutional Impact in Dive…