City University of Hong Kong

Derek Ho

Xinyu Zhou

Wingshing Chan

Xin Yu Zhou

Wing Shing Chan

Shao Yong Zheng

Shaoyong Zheng

Xiaohu Fang

Ying Wang

Shi Chang Chen

Wenrong Yan

Liping Wei

Yi Tian

Liheng Zhou

The present disclosure provides a gas sensor comprising a gas sensing layer fabricated based on a solution-processed, template-free synthesis method that achieves controllable ZnO nanostructured morphologies. The method is based on promotion and suppression of growth at specific crystallographic dimensions by tuning the polarity of the solvent. The gas sensing layer with the ZnO nanostructures exhibits high response, excellent selectivity and rapid recovery time.

Method for fabricating zinc oxide nanostructures and gas sensors

A power amplifier includes an active device and an output matching circuit operably connected with the active device. The output matching circuit includes a bandpass impedance transformer, in particular, a multimode bandpass impedance transformer. The multimode bandpass impedance transformer may include a multimode resonator and coupling feed lines.

Power amplifier

A Doherty power amplifier circuit having a main power amplification device, an auxiliary power amplification device arranged in parallel with the main power amplification device, and a load modulation circuit comprising a harmonic injection circuit connected with respective outputs of the main power amplification device and the auxiliary power amplification device. The harmonic injection circuit is arranged to transfer harmonic components generated at the main power amplification device to the auxiliary power amplification device and harmonic components generated at the auxiliary power amplification device to the main power amplification device, when both the main and auxiliary power amplification devices are operating, for modulating the respective outputs of the main power amplification device and the auxiliary power amplification device.

Doherty power amplifier circuit

A Doherty power amplifier having a main power amplification device and an auxiliary power amplification device arranged in parallel with the main power amplification device includes a load modulation circuit having a harmonic injection circuit connected with respective outputs of the main power amplification device and the auxiliary power amplification device. The harmonic injection circuit is arranged to provide a phase shift to simultaneously modulate transfer of second harmonic components generated at the main power amplification device to the auxiliary power amplification device and transfer of second harmonic components generated at the auxiliary power amplification device to the main power amplification device, when the main power amplification device and the auxiliary power amplification device are operated at saturation.

Wideband Doherty high efficiency power amplifier

A method for determining a concentration of an analyte in a subject includes irradiating a part of the subject with electromagnetic radiation, wherein a part of the subject comprises biological molecules arranged to absorb the electromagnetic radiation and to emit fluorescence in response. The method also includes measuring fluorescence emitted to obtain data representative of a fluorescence decay. The method further includes processing the data to determine one or more feature points associated with the fluorescence decay and to generate one or more feature vectors based on the one or more feature points, and applying the one or more feature vectors to a regression model for the analyte to determine the concentration of the analyte. Also provided is a system for determining a concentration of an analyte in a subject, as well as a measurement device for facilitating determination of a concentration of an analyte in a subject.

Determination of a concentration of an analyte in a subject

A Doherty power amplifier includes a main device in a main amplifier circuit and an auxiliary device in an auxiliary amplifier circuit arranged in parallel with the main amplifier circuit. The Doherty power amplifier further includes a load modulation network including a first open-circuited transmission line connected to an output of the main device; a second open-circuited transmission line connected to an output of the auxiliary device; and an impedance transformation and phase compensation network connected with the output of the main device and the output of the auxiliary device for providing a combined output power. The first and second open-circuited transmission lines are arranged directly adjacent one another to form, during operation, a mutual coupling therebetween.

Growing community of inventors

Hong Kong, China

Derek Ho