Publications

This Work-In-Progress paper details the process and lessons learned when converting a hands-on engineering minicourse to a scalable, self-paced Massively Open Online Course (MOOC). Online courseware has been part of academic and industry training and learning for decades. Learning activities in online courses strive to mimic in-person delivery by including...

Analog self-interference mitigation techniques are currently being investigated in a variety of operational settings for In-Band Full-Duplex (IBFD) systems. The significant multipath effects of realistic environments, such as inside buildings, can severely limit performance. The influence of different transceiver parameters on the effectiveness of a four-tap RF canceller using a...

A new architecture is proposed for achieving Simultaneous Transmit and Receive (STAR) with a digital phased array. We demonstrate how digital beamforming and cancellation enables adjacent transmitting and receiving sub-arrays to operate simultaneously in the same frequency band without a significant reduction in performance. Our approach uses only digital signal...

Antenna radiation patterns are typically measured using network analyzers, which are both expensive and physically large in size. These drawbacks can limit this test equipment's usage in universities that cannot afford to make such a purchase, as well as within applications that require mobile antenna measurements. An alternative approach is...

Many in-band full-duplex wireless systems transmit and receive on a single antenna to minimize redundancy and maintain compact form factors. For effective operation, all of these systems need to maximize transmit-to-receive isolation, which is limited by non-ideal antenna matching and non-zero circulator leakage. Several isolation-improvement techniques are investigated in this...

In-band full-duplex wireless communications are challenging because they require the mitigation of self-interference caused by the co-located transmitter to operate effectively. This paper presents a novel tapped delay line RF canceller architecture with multiple non-uniform pre-weighted taps to improve system isolation by cancelling both the direct antenna coupling as well...

Many wireless devices have requirements that emphasize low size, weight and power for increased functionality and extended lifetimes. The additional complexity of these devices mandates the need to dynamically verify that all sub-system functions are fully operational. These tests can only be performed internal to the unit, and a circuit...

Simultaneous Transmit and Receive (STAR) systems typically utilize multiple cancellation layers to improve system isolation and avoid self-interference. The design of these different layers must be evaluated both individually and as a whole to determine their effectiveness in various environments. A flexible and reusable mobile testbed was constructed to aid...

Vehicle-to-vehicle communication systems promise enhanced safety for passengers, but require access to a crowded wireless spectrum to enable their data links. Simultaneous Transmit and Receive (STAR) systems can facilitate this spectrum access by increasing the number of users within a given frequency band. Since high isolation is needed for STAR...

Simultaneous Transmit and Receive operation requires a high amount of transmit-to-receive isolation in order to avoid self-interference. This isolation is best achieved by utilizing multiple cancellation techniques. The combination of adaptive multiple-input multiple-output spatial cancellation with a high-isolation antenna and RF canceller produces a novel system architecture that focuses on...