The University of North Carolina at Charlotte

Other

Thomas Paul Weldon

David M Binkley

Rafic Zein Makki

Ali Chehab

Konrad Miehle

Ryan S Adams

Kerry Rebecca Weldon

Kristen Marie Weldon

A method to implement circuits and circuit elements having one or more ports may include digitizing, using analog-to-digital converters, continuous-time input signals received from one or more ports of a circuit to form discrete-time input signals. At a digital signal processor, the discrete-time input signals are received and the discrete-time input signals are processed to calculate a desired discrete-time output signals. Using digital-to-analog converters, the calculated desired discrete-time output signal are calculated to form outputs of continuous-time output signals at the one or more ports of the circuit. The continuous-time output signals are output to the same one or more ports that receive the continuous-time input signals; and producing, thereby, a desired relationship between the continuous-time output signals and the continuous-time input signals at the one or more ports.

Digital discrete-time non-foster circuits and elements

A metamaterial simultaneously exhibiting a relative effective permeability and a relative effective permittivity below unity over a wide bandwidth, including: one of a two-dimensional and a three-dimensional arrangement of unit cells, wherein each of the unit cells has a magnetic dipole moment and an electric dipole moment that are dependent upon one or more of an incident magnetic field and an incident electric field; and a coupling mechanism operable for coupling one or more of the incident magnetic field and the incident electric field to one or more devices. Optionally, the coupling mechanism includes one or more of a split ring and a pair of parallel plates coupled by one of a rod and a wire. The one or more devices are non-Foster elements.

Wideband negative-permittivity and negative-permeability metamaterials utilizing non-foster elements

Methods and apparatus are provided for testing to determine the existence of defects and faults in circuits, devices, and systems such as digital integrated circuits, SRAM memory, mixed signal circuits, and the like. In particular, methods and apparatus are provided for detecting faults in circuits, devices, and systems using input control signals to generate controlled-duration, controlled pulse-width, transient power supply currents in a device under test, where said transient power supply currents are of controllable bandwidth and can be used as observables to determine faulty or defective operation. Additionally, methods and apparatus are provided to permit high bandwidth sensing of transient supply currents as need to preserve the narrow widths of these current pulses. These methods may include autozero techniques to remove supply current leakage current and DC offsets associated with practical current sensing currents. The sensed transient supply currents can be compared to single or multiple thresholds to assess normal or faulty or defective operation of the device under test.

Methods and apparatus for testing electronic circuits

Methods and apparatus are provided for substantially reducing and/or canceling nonlinearities of any order in circuits, devices, and systems such as amplifiers and mixers. In particular, methods and apparatus are provided for substantially reducing and/or canceling third order nonlinearities in circuits, devices, and systems such as amplifiers and mixers. A first coupler is used to split an input signal into two equal-amplitude in-phase components, each component is processed by two nonlinear devices with different nonlinearities, and a final combiner, such as a 180-degree hybrid, recombines the processed signals 180 degrees out of phase and substantially reduces and/or cancels the undesired nonlinear distortion components arising due to nonlinearities in the nonlinear devices.

Methods and apparatus for substantially reducing nonlinear distortion

Methods and apparatus for substantially reducing third order intermodulation distortion and other nonlinear distortions

Methods and apparatus for substantially reducing nonlinear distortion using multiple nonlinear devices

Methods and apparatus for using Taylor series expansion concepts to substantially reduce nonlinear distortion

Method and apparatus for cancellation of third order intermodulation distortion and other nonlinearities

Surface pattern applied to a doughnut pastry

A directional antenna for telecomunication base station applications for home or business is provided. A folded dipole, a passive reflector, a balun and selectively routed coaxial transmission line all enclosed in a plastic enclosure provide improved stability of operating parameters when subjected to significant installation variations. The use of a PVC or similar plastic enclosure results in increased bandwidth while permitting printed circuit techniques and similar electronic construction methods the necessary protection and structural integrity.

Enclosed dipole antenna and feeder system

Growing community of inventors

Charlotte, NC, United States of America

Thomas Paul Weldon