This paper studies a number of quantized feedback design problems for linear systems. We consider the case where quantizers are static (memoryless). The common aim of these design problems is to stabilize the given system or to achieve certain performance with the coarsest quantization density. Our main discovery is that the classical sector bound approach is nonconservative for studying these design problems. Consequently, we are able to convert many quantized feedback design problems to well-known robust control problems with sector bound uncertainties. In particular, we derive the coarsest quantization densities for stabilization for multiple-input-multiple-output systems in both state feedback and output feedback cases; and we also derive conditions for quantized feedback control for quadratic cost and H/sub /spl infin// performances.

The sector bound approach to quantized feedback control | NOVA. The University of Newcastle's Digital Repository

The realization of integrated, low-cost and efficient solutions for high-speed, on-chip communication requires terahertz-frequency waveguides and has great potential for information and communication technologies, including sixth-generation (6G) wireless communication, terahertz integrated circuits, and interconnects for intrachip and interchip communication. However, conventional approaches to terahertz waveguiding suffer from sensitivity to defects and sharp bends. Here, building on the topological phase of light, we experimentally demonstrate robust terahertz topological valley transport through several sharp bends on the all-silicon chip. The valley kink states are excellent information carriers owing to their robustness, single-mode propagation and linear dispersion. By leveraging such states, we demonstrate error-free communication through a highly twisted domain wall at an unprecedented data transfer rate (exceeding ten gigabits per second) that enables real-time transmission of uncompressed 4K high-definition video (that is, with a horizontal display resolution of approximately 4,000 pixels). Terahertz communication with topological devices opens a route towards terabit-per-second datalinks that could enable artificial intelligence and cloud-based technologies, including autonomous driving, healthcare, precision manufacturing and holographic communication. Robust terahertz wave transport is demonstrated on a silicon chip using the valley Hall topological phase. Error-free communication is achieved at a data rate of 11 Gbit s−1, enabling real-time transmission of uncompressed 4K high-definition video.

/pdf/terahertz-topological-photonics-for-on-chip-communication-2rgzb87m58.pdf

Terahertz topological photonics for on-chip communication

In vivo methods for drug absorption – Comparative physiologies, model selection, correlations with in vitro methods (IVIVC), and applications for formulation/API/excipient characterization including food effects

The kinase ataxia telangiectasia mutated and rad3 related (ATR) is a key regulator of the DNA-damage response and the apical kinase which orchestrates the cellular processes that repair stalled replication forks (replication stress) and associated DNA double-strand breaks. Inhibition of repair pathways mediated by ATR in a context where alternative pathways are less active is expected to aid clinical response by increasing replication stress. Here we describe the development of the clinical candidate 2 (AZD6738), a potent and selective sulfoximine morpholinopyrimidine ATR inhibitor with excellent preclinical physicochemical and pharmacokinetic (PK) characteristics. Compound 2 was developed improving aqueous solubility and eliminating CYP3A4 time-dependent inhibition starting from the earlier described inhibitor 1 (AZ20). The clinical candidate 2 has favorable human PK suitable for once or twice daily dosing and achieves biologically effective exposure at moderate doses. Compound 2 is currently being teste...

Discovery and Characterization of AZD6738, a Potent Inhibitor of Ataxia Telangiectasia Mutated and Rad3 Related (ATR) Kinase with Application as an Anticancer Agent.

The gastrointestinal (GI) absorption of orally administered drugs is determined by not only the permeability of GI mucosa but also the transit rate in the GI tract. It is well known that the gastric emptying rate is an important factor affecting the plasma concentration profile of orally administered drugs, and the intestinal transit rate also has a significant influence on the drug absorption, since it determines the residence time of the drug in the absorption site. The reason why the residence time is also a critical factor for drug absorption is that there is the site difference in absorbability for some drugs. We have developed the GI-Transit-Absorption Model (GITA Model) to analyze and predict the drug absorption kinetics by taking into account both the two factors, ie. GI transit and drug absorbability including its site difference. GITA Model has been already evidenced to be very useful for estimating the absorption kinetics of drugs with various characteristics and applied to assess the human data in combination with the gamma scintigraphy. In this review, the importance of GI transit rate in determining the absorption kinetics and the bioavailability of orally administered drugs is discussed mainly employing GITA Model and the results obtained by the model.

Gastrointestinal transit and drug absorption

This letter presents a high-performance fully integrated GaAs MMIC power amplifier (PA) fabricated in 0.15 $\mu$ m pHEMT process. The MMIC PA is operating from 2–6.5 GHz, covering the band of the LTE, wifi and WiMAX. A flat small-signal gain of 25.5 dB is achieved by utilizing novel input matching networks. The large-signal measurement shows that the peak output power is above 31 dBm for the whole bandwidth with a power gain of 21 dB, while the corresponding power-added efficiency (PAE) is between 31.4%–51.5%. An adjacent channel leakage radio (ACLR) obtains ${-}30$ dBc at 25 dBm output power, tested with WCDMA and LTE signals, and reaches ${-}45$ dBc after digital pre-distortion (DPD). The circuit structure and design method are also suitable for GaN process to achieve higher power.

A High-Efficiency GaAs MMIC Power Amplifier for Multi-Standard System

This paper presents for the first time the design, fabrication, and demonstration of a dielectric waveguide (DWG)-based ortho-mode sub-THz interconnect channel for planar chip-to-chip communications. By combining the proposed new transition of microstrip line with DWG orthogonally, the ortho-mode transition is constructed to form an ortho-mode channel. The measured minimum insertion losses for the $E_{y11}$ mode and the $E_{x11}$ mode are 6.6 dB with 20.3-GHz 3-dB bandwidth and 6.5 dB with 55.2-GHz 3-dB bandwidth, respectively. The simulation and measurement results agree well with each other.

Ortho-Mode Sub-THz Interconnect Channel for Planar Chip-to-Chip Communications

Demonstrated is a 2-4 GHz wideband power amplifier (WPA) using Cree 10 W GaN HEMT CGH40010. Also a novel process to find the optimum impedances is presented, with which the gain flatness can be taken into account. A compact PCB has been fabricated and tested with continuous waves at low (20 dBm) and high (28 dBm) input power level. From the measured results, at low power level, the gain is 13.1-14.1 dB across 2.0-3.9 GHz and 12.3-14.1 dB across 2.0-4.0 GHz. For large signals, power gain is 11.1-12.6 dB with power-added efficiency (PAE) 36.5-53.4% while output power is around 40 dBm. Gain flatness keeps less than 1 dB beyond 95% of the band. For a 5 MHz WCDMA signal, the adjacent channel leakage ratio of the WPA with digital predistortion reaches - 45.3 dBc with an average drain efficiency of 46.7%.

https://ietresearch.onlinelibrary.wiley.com/doi/epdf/10.1049/el.2012.4135

2-4 GHz wideband power amplifier with ultra-flat gain and high PAE

Developability assessment of clinical drug products with maximum absorbable doses.

The invention provides a radio frequency power amplification device, which comprises a digital control circuit, a driver stage amplifier and a Doherty power amplifier, wherein the digital control circuit consists of a coupler, a signal power detection circuit and a grid voltage control circuit; and the digital control circuit adjusts the grid voltage of main power amplifiers in the driver stage amplifier and the Doherty power amplifier according to the signal power, so that the amplifier system has the optimal linearity A signal amplification module consists of the driver stage amplifier and the Doherty power amplifier, wherein the driver stage amplifier is biased in AB classes and guarantees high linearity and gain; and the Doherty power amplifier guarantees high efficiency of the system The radio frequency power amplification device is a high-efficiency high-linearity radio frequency power amplifier and is applied to a wireless communication transmitter

Xuan Ding

Papers

A High-Efficiency GaAs MMIC Power Amplifier for Multi-Standard System

Ortho-Mode Sub-THz Interconnect Channel for Planar Chip-to-Chip Communications

2-4 GHz wideband power amplifier with ultra-flat gain and high PAE

Developability assessment of clinical drug products with maximum absorbable doses.

Radio frequency power amplification device