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III-Nitride Metal-Oxide-Semiconductor Heterojunction (MOSH) structure consists of a thin dielectric layer deposited on top of a semiconductor heterostructure with a 2D electron gas at the heterojunction interface. MOSH structures are the key components for high-power low-loss, fast RF switches. The paper discusses two types of high-power switches using III-Nitride MOSH structures. The first type uses the MOSH structure as the gate region of an AlGaN/GaN HFET. The second type uses MOSH structure as a switching capacitor. In the 2GHz - 10 GHz frequency range, switching powers from 20 to 60 W/mm have been achieved with the insertion loss below 1 dB.

This paper reviews our work on the development of microwave carbon nanotube resonator sensors for gas detection. The sensor consists of a radio frequency resonator coated with a layer of carbon nanotubes. Upon exposure to gasses, the resonant frequency of the sensor shifts to indicate the presence of gasses. Our experimental results demonstrate that the microwave carbon nanotube resonator sensor achieves a sensitivity of 4000 Hz/ppm upon exposure to ammonia and the resonant frequency is recovered when ammonia is evacuated. The sensing mechanism is dependent on electron transfer from the ammonia to the nanotubes. This sensor platform has great potential for wireless sensing network applications.

In this paper, a surface acoustic wave (SAW) biosensor with gold delay area on LiNbO₃ substrate detecting DNA sequences is proposed. By well-designed device parameters of the SAW sensor, it achieves a high performance for highly sensitive detection of target DNA. In addition, an effective biological treatment method for DNA immobilization and abundant experimental verification of the sensing effect have made it a reliable device in DNA detection. The loading mass of the probe and target DNA sequences is obtained from the frequency shifts, which are big enough in this work due to an effective biological treatment. The experimental results show that the biosensor has a high sensitivity of 1.2 pg/ml/Hz and high selectivity characteristic is also verified by the few responses of other substances. In combination with wireless transceiver, we develop a wireless receiving and processing system that can directly display the detection results.

The paper emphasizes methods, architectures, and components for system-on-chip design. It describes the basic knowledge and skills for designing high-performance low-power embedded devices whose complexity increases exponentially, as so does the effort of designing them. Relying upon an appropriate design methodology which concentrates on reuse, executable specifications, and early error detection, these complexities can be mastered. The paper bundles these topics in order to provide a good understanding of all the problems involved. It shows how to go from description and verification to implementation and testing, presenting three systems-on-chip for three different wireless applications based on configurable processors and custom hardware accelerators.

Wireless communication standard continues to evolve in order to fulfill the demand for high data rate operation. This leads to the exertion on the design of radio frequency power amplifier (RFPA) which consumes high DC power in order to support linear transmission of high data rate signal. Hence, operating the PA with low DC power consumption without trading-off the linearity is vital in order to achieve the goal of achieving fully integrated system-on-chip (SoC) solution for 4G and 5G transceivers. In this paper, the evolution of CMOS PA toward achieving a fully integrated transceiver solution is discussed through the review of multifarious CMOS PA design. This is categorized into the review of efficiency enhancement designs followed by linearity enhancement designs of the CMOS PA.

In this paper, a monitoring technique based on the wireless sensor network is investigated. The sensor nodes used for monitoring are developed in a simulation environment. Accordingly, the structure and workflow of wireless sensor network nodes are designed. Time-division multiple access (TDMA) protocol has been chosen as the medium access technique to ensure that the designed technique operates in an energy-efficient manner and packet collisions are not experienced. Fading channels, i.e., no interference, Ricean and Rayleigh, are taken into consideration. Energy consumption is decreased with the help of ad-hoc communication of sensor nodes. Throughput performance for different wireless fading channels and energy consumption are evaluated. The simulation results show that the sensor network can quickly collect medium information and transmit data to the processing center in real time. Besides, the proposed technique suggests the usefulness of wireless sensor networks in the terrestrial areas.

In this work, we have used a novel adaptive neuro-fuzzy inference system (ANFIS) method to design and fabricate a high-performance microstrip diplexer. For developing the proposed ANFIS model, the hybrid learning method consisting of least square estimation and back-propagation (BP) techniques is utilized. To achieve a compact diplexer, a designing process written in MATLAB 7.4 software is introduced based on the proposed ANFIS model. The basic microstrip resonator used in this study is mathematically analyzed. The designed microstrip diplexer operates at 2.2GHz and 5.1GHz for wideband wireless applications. Compared to the previous works, it has the minimum insertion losses and the smallest area of 0.007 ${\lambda }_g^2$ (72.2mm²). It has flat channels with very low group delays (GDs) and wide fractional bandwidths (FBWs). The GDs at its lower and upper channels are only 0.48ns and 0.76ns, respectively. Another advantage of this work is its suppressed harmonics up to 12.9GHz (5th harmonic). To design the proposed diplexer, an LC model of the presented resonator is introduced and analyzed. To verify the simulation results and the presented ANFIS method, we fabricated and measured the proposed diplexer. The results show that both simulations and measurements data are in good agreement, which give reliability to the proposed ANFIS method.

This paper presents the development of a three-channel telemetry system using Microchip rfPIC12F675 as transmitter and using rfRXD0420 as receiver. The highly integrated radio frequency IC chip features the system which is simple in structure, compact in size and low in power consumption. Using 3V power supply for the transmitter, the system is able to transmit low amplitude signal from 8 m to more than 50 m with power consumption as low as 10 mW. The biotelemetry system can be used in human or animal bio-signal acquisition and monitoring.

The capability of seamlessly switching between two communication protocols will be very important for communication devices of the future, since it allows the end users to judiciously use whichever network is appropriate, depending on cost, signal strength or other factors such as the amount of battery life left on the device. This paper presents the groundbreaking idea of a Seamless Protocol Switching Layer (SPSL) on a hardware and software level to solve this problem. In addition, the SPSL concept is implemented by developing a prototype application, a Smart Video Phone, built using Intel XScale-based PXA255 board and ARM Linux as the operating system that can seamlessly switch between IEEE 802.11 and Bluetooth technologies. Experiments show that if the signal of the Bluetooth signal goes below 40%, the switching to Wireless-Fidelity (Wi-Fi) happens if it is available.

Error correcting codes are well known techniques for improving bit error rate (BER) performance in digital communication systems and are particularly important in wireless information networks to help establish reliable communication links. This paper examines the effect of coder/decoder circuitry failures on the overall communication system performance. A system analysis of the error correction coding scheme performance must include an evaluation of the reliability of the coder/decoder circuitry because their failures also serve as a source of undetected errors. The parity bit code, Hamming single error correcting and detecting code, and the Reed–Solomon code are included in the study. Results reveal that for applications as described in the text that require low bit error rate and operate at low data rates, the reliability of the coding circuitry can play a significant role in determining overall system performance. In fact, for such error and data rates, a simpler coding scheme with higher circuit reliability may actually be more beneficial than a more complex coding scheme with enhanced error correcting ability but with a higher chip failure rate.

The following topics are under this section:

• Asia-Pacific — Early treatment of vision and hearing problems can contribute to enhancing health for older adults
• Asia-Pacific — Study finds association between Attention Deficit Hyperactivity Disorder various biomarkers and health conditions
• Asia-Pacific — Japanese scientists discover new species of non-blooming orchids on Japanese subtropical islands
• Asia-Pacific — Improving sleep quality through short mindfulness training programmes
• Asia-Pacific — Breakthrough research in genetic engineering for precision agriculture boosts microbial manufacturing
• Asia-Pacific — Alteration of intrinsic properties of non-magnetized metals using light
• Asia-Pacific — Wireless manipulation of brain cells to help in neurological disease management
• Asia-Pacific — Relieving bottleneck in photosynthesis may have a major impact on food crops
• Asia-Pacific — Cardiac regeneration through novel dual stem cell therapy
• Rest of the World — American Heart Association advices prescription of omega-3 fatty acid medications to lower triglyceride levels
• Rest of the World — Evasion of immunodeficiency viruses by our ancestors
• Rest of the World — Detection of unreported cases of Zika virus during 2017 outbreak
• Rest of the World — How scorpion toxin is helping researchers solve the mystery of chronic pain

The following topics are under this section:

• Supporting Patients in Management of Diabetes
• Connectivity in the MedTech Sector

This study compares the emergence of four wireless clusters in the 1970s and 1980s. Two of them, Calgary in Canada and Finland, initially pursued rather similar service innovations for not very different markets but with very different outcomes, which raises the question why. One major reason that emerges from the reviewed extant research on cluster emergence and innovation diffusion concerns the differences in timing and quality of the initial innovations, affecting their respective perceived diffusion attributes, and market growth and extent. The initial innovation in Finland was well received, diffused rapidly and eventually globally, and led to a positive spiral spurring the industry on to take a global lead. In the case of Calgary, however, it was un-competitive in the broader international market, forcing the anchor firm to adapt and reorient. The study analyses and compares the characteristics of the respective initial innovations and their impact on the outcome, and concludes with a discussion and some propositions on cluster emergence. Enhanced understanding of nascent clusters, especially regarding the role of globally attractive initial innovations and their diffusion quality and timing, should provide value for both scholars and practitioners.

This paper reviews our work on the development of microwave carbon nanotube resonator sensors for gas detection. The sensor consists of a radio frequency resonator coated with a layer of carbon nanotubes. Upon exposure to gasses, the resonant frequency of the sensor shifts to indicate the presence of gasses. Our experimental results demonstrate that the microwave carbon nanotube resonator sensor achieves a sensitivity of 4000 Hz/ppm upon exposure to ammonia and the resonant frequency is recovered when ammonia is evacuated. The sensing mechanism is dependent on electron transfer from the ammonia to the nanotubes. This sensor platform has great potential for wireless sensing network applications.

Virtual environments that build pervasive communities have become one of the fastest growing research fields in the last years. This paper presents a novel architecture for providing a wireless backbone system as basic communication infrastructure for pervasive communities. Self-organisation as a fundamental aspect is used by all components, leading to an autonomic system.

Mobile video streaming is a technique that the receiver could continuously view the video content while receiving the data. An interactive framework of mobile video streaming is presented in a practical way. To reduce the effects caused by the fluctuation of wireless network, an adaptive rate control method is proposed for priority process streaming with QoS control. The transmitting data rate adapts to a suitable level according to the network status. Simulation scenario has been created to help analyse the behaviour of adaptive streaming over wireless channel. Both cases with and without the proposed method were examined and the result shows the proposed modal is able to improve the overall performance in cases when the channel conditions fluctuate.

Due to the limited bandwidth of wireless transmission, in this paper we present an efficient scheme of wireless monitor system. The scheme adopts an improved fast SPIHT algorithm to encode video image in combination with the strategy of ROI (Region of interest) with priority. With regard to the problem how to separate ROI and non-ROI, we introduced a background modeling method based on statistics, which can adapt to the changing environment. Furthermore, the scheme produces an embedded stream, supports successive transmission, the rate of coding image can be accurately controlled; it not only rationally utilized network bandwidth, but also made the best of wavelet's advanced speciality.

III-Nitride Metal-Oxide-Semiconductor Heterojunction (MOSH) structure consists of a thin dielectric layer deposited on top of a semiconductor heterostructure with a 2D electron gas at the heterojunction interface. MOSH structures are the key components for high-power low-loss, fast RF switches. The paper discusses two types of high-power switches using III-Nitride MOSH structures. The first type uses the MOSH structure as the gate region of an AlGaN/GaN HFET. The second type uses MOSH structure as a switching capacitor. In the 2GHz - 10 GHz frequency range, switching powers from 20 to 60 W/mm have been achieved with the insertion loss below 1 dB.

Global vision consensus on the next generation of wireless mobile communications, broadly termed 4G, sketches a heterogeneous infrastructure, comprising different wireless access systems in a complementary manner and vested with reconfiguration capabilities that will facilitate a more flexible and dynamic adaptation of the wireless infrastructure to meet the ever-changing service requirements. We present the generic stages of reconfiguration procedures and identify the management requirements in the context of these stages. Next, we introduce a generic, platform-independent reconfiguration management framework to be hosted on end systems and elaborate on its main components.

The key objective of wireless sensor networks (WSNS) is to use the restricted embedded resource efficiently and to maximize their life time. Quality of service (QoS) routing is one of the key technologies to provide differential services and utilize the whole resource effectively for WSNS. We present a new energy best routing method which could meet the requirements of QoS bandwidth and has longer network life time.

This method Constructed the Node Selection Model, Energy Assessing Model. The genetic quantum Algorithm (QGA) which utilizes the set of the available nodes was used to construct the route. The Markov chain proved the algorithm that is strong convergence and also the convergence speed is exponent. In addition, the choosing intervals of the controlling parameters proposed by the QGA algorithm have been determined based on the simulations and the analysis results. It has been shown from the experiments that the energy best routing method has better adaptability and longer lifetime.