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This paper presents the investigation results of low actuation voltage for RF MEMS capacitive switches using three electrodes topology. The main purpose of the investigation is to verify the reduction of actuation voltage as a result of applying three electrodes in RF MEMS. The new switch structure emphasizes three parallel electrodes instead of two electrodes as in previous structure. In the design stage all performance factors include beam width, beam length, area and beam thickness have been optimized to ensure the best physical dimension of the switch. The investigation of the performance was carried out using Architect Coventorware. Preliminary results shows that the actuation voltage of the three parallel electrodes switch gives very significant reduction of actuation voltage which is approximately half compared to other topologies or standard structure using two parallel electrodes.

The application of wireless sensor network for process monitoring of laser cutting process is a promising solution to address the problems in achieving good cutting performance. Wireless sensor network provide real time data monitoring flexibility, maintenance convenient, and easy to relocation for laser cutting process application. This paper presents the development of wireless sensor network for monitoring temperature at cutting surfaces during laser cutting process. The system consists of thermocouple sensors, microcontroller programmable system on chip platform, wireless radio frequency and software data logger. The workability and performance of the system was tested by using gas cutting.

Accelerated advancement in the world of microprocessor necessitates solving the bus contention in a most efficient manner. The major challenge is to reduce the latency of the system and to achieve a fair bandwidth allocation using maximum CPU utilization. Combination of Adaptive Arbitration algorithm and the processors according to their traffic behavior can be one of the feasible options to tackle the aforesaid problems due to its fair bandwidth allotment and low system latency. This article provides a comprehensive picture of research and developments in dynamic arbitration algorithm for masters according to the traffic behavior. The papers published in standard journals are reviewed, classified according to their objectives and presented with a general conclusion.

This chapter presents performance of a new technique for constructing Quasi-Cyclic Low-Density Parity-Check (QC-LDPC) encrypted codes based on a row division method. The new QC-LDPC encrypted codes are flexible in terms of large girth, multiple code rates, and large block lengths. In the proposed algorithm, the restructuring of the interconnections is developed by splitting the rows into subrows. This row division reduces the load on the processing node and ultimately reduces the hardware complexity. In this method of encrypted code construction, rows are used to form a distance graph. They are then transformed to a parity-check matrix in order to acquire the desired girth. In this work, matrices are divided into small sub-matrices, which result in improved decoding performance and reduce waiting time of the messages to be updated. Matrix sub-division increases the number of sub-matrices to be managed and memory requirement. Moreover, Prototype architecture of the LDPC codes has been implemented by writing Hardware Description Language (VHDL) code and targeted to a Xilinx Spartan-3E XC3S500E FPGA chip.

This paper discusses a design of single path low noise amplifier (LNA) architecture with variable capacitor switching, which can switch between standards of GSM 850 MHz and GSM 1.8 GHz. The LNA is designed using Silterra 0.18 µm CMOS technology process. The inductively degenerated cascode low noise amplifier topology has been adopted to develop this switchable LNA architecture. The post-layout simulations of the multi-standard LNA at 850 MHz for the input matching S 11 is −12.74 dB, reverse isolation S 12 is −55 dB, power gain S 21 is 10.67 dB, and output matching S 22 is −15.2 dB. On the other hand, the post-layout simulations at 1.8 GHz for the input matching S 11 is −6.9 dB, reverse isolation S 12 is −43.94 dB, power gain S 21 is 14.13 dB, and output matching S 22 is −11.36 dB. The noise figure of the multi-standard LNA at 1.8 GHz is 2.64 dB and 850 MHz is 3.92 dB. The total power consumption for both frequencies is 41.6 mW. The die size is 1.65 mm × 1.80 mm.

This paper presents the design of a multi-standard low noise amplifier (LNA) with the capability to switch between 1.9-GHz W-CDMA standard and 0.9-GHz GSM standard. Frequency band selection of the multi-standard LNA is implemented by using inductive, capacitive and resistive switching. The design is implemented by using Silterra 0.18-µm CMOS technology process with the supply voltage of 1.8V. The post-layout simulations of the multi-standard LNA at W-CDMA 1.9 GHz for the input matching S 11 is −9.74 dB, reverse isolation S 12 is −53.01 dB, power gain S 21 is 12.18 dB, and output matching S 22 is −12.41 dB. On the other hand, the post-layout simulations at GSM 0.9 GHz for the input matching S 11 is −10.45 dB, reverse isolation S 12 is −63.13 dB, power gain S 21 is 10.24 dB, and output matching S 22 is −13.64 dB. The noise figure of the multi-standard LNA at W-CDMA 1.9 GHz is 2.62 dB and GSM 0.9 GHz is 3.56 dB. The total power consumption is 33.1 mW when the multi-standard LNA is operating at 1.9-GHz W-CDMA standard 0.9-GHz GSM standard. The voltage supplied to the CMOS switches is 3 V. The die size is 1.65 mm × 1.80 mm.

The market for wireless sensor networks (WSNs) is rapidly growing, yet limited by batteries with short lifetimes. Providing a green, virtually infinite alternative power source to traditional energy sources will significantly expand the applications for WSNs and other technologies. The use of piezoelectric materials to capitalize on the ambient vibrations surrounding a system is a method that presents dramatic potential for power harvesting. The simplicity associated with piezoelectric micro-generators makes MEMS applications highly attractive. In such applications, mechanical vibrations from environment are harvested and converted into electrical energy. These micro-generators are designed as an alternative to a battery-based solution that is especially intended for remote systems. We propose a comparative study on the obtained results of the energy delivered from the ambient vibration-based MEMS energy harvester using the ANSYS and COVENTORWARE approaches. The improvement reflected in the experimental results for vibration-based MEMS piezoelectric energy harvesters indicates excellent application scope in power MEMS and green energy.

This paper presents the analysis of modeling for artificial lateral line flow sensor. An artificial hair cell sensor is the current technology that based on a biological inspiration and widely used in underwater applications including glider, robotic and autonomous surface vehicle (ASV). The structure of the lateral line flow sensor is consisting of cantilever beam and four hair cells attached perpendicular to the cantilever beam at the free end. The lateral line sensor with different height of hair cells are modeled and simulated with water flow rate 0 m/s to 1 m/s. High sensitivity is achieved by increasing a hair cells length and use low young modulus material for a cantilever beam. The maximum stress was analyzed in order to identify the limitation of the sensor.

Rapid advancement in the world of microprocessor necessitates solving the bus contention in a most efficient manner. The major challenge is to reduce the latency of the system and to achieve a fair bandwidth allocation. Combination of Adaptive Arbitration algorithm and the processors according to their traffic behavior can be one of the feasible options to tackle the aforesaid problems due to its fair bandwidth allotment and low system latency. This article provides a comprehensive picture of the global scenario of Adaptive Arbitration algorithm for fair bandwidth allocation so as to enable researchers to decide the direction of further investigation. Some of the works published so far in this area are reviewed, classified according to their objectives and presented in an organized manner with general conclusion.

This paper describes implementation of an offset quadrature phase shift keying (OQPSK)-pulse-shaping block as a part of digital transmitter. The implementation is based on 2.4 GHz-band IEEE 802.15.4 standard. In this paper, the implementation results are compared to the results of OQPSK modulator and pulse-shaping block in terms of simulation waveform, design size, and synthesis run time. These blocks were designed using Verilog code through Xilinx ISE as a new design method and been implemented on Spartan3E XC3S500E field programmable gate array (FPGA). Current review shows that configurations for the implementation of OQPSK-pulse-shaping block, require 26.4% slices, 22.9% sliced flip-flops, and 15.5% look-up tables (LUTs), which is much better than the results of OQPSK modulator and pulse-shaping block. At clock frequencies of 2 MHz and 25 MHz, the synthesis run time for OQPSK-pulse-shaping block shows substantial improvement with 48 ns faster than the two blocks.

This paper represents the temperature effect on silicon nanowire transistor and the possibility of using it as a temperature nanosensor. MuGFET simulation tool was used to investigate temperature characteristics of the nanowire transistors. Current-voltage characteristics with different values of temperature were simulated. Variation of sub threshold slope (SS), ON current to OFF current ratio (Ion/Ioff) and drain induced barrier lowering (DBIL) with working temperature was investigated. MOS diode connection suggested using the silicon nanowire transistor as a temperature nanosensor.

Extended Kalman Filter (EKF) has been successfully utilized in a number of satellites. However, compared to other attitude determination methods developed, it is one of the most computationally burdening algorithm and with the new trend of using nano-satellites which have limited electrical power, mass, space and usually budget, it is essential to design an attitude determination system (ADS) which conforms to this limitation. Therefore, in this paper, as an improvement on the InnoSAT project which incorrectly runs the EKF algorithm on the RCM3400, the CPU is replaced with the ARM7TDMI microprocessor to successfully perform attitude determination of InnoSAT using the EKF. The ARM7TDMI has been chosen since it is one of the well-known microprocessor used in various electronic equipment because it is low power and robust. It is also off the shelf which means it is easily available thus making it a cheaper solution than a space grade component. Analysis on the ARM7TDMI was done based on attitude data accuracy and execution time.

The wireless sensor network market is growing quickly yet is limited by existing short lifetime batteries. Providing a green, virtually infinite alternative power source to traditional energy sources will significantly expand applications for WSNs and other technologies, the use of piezoelectric materials to capitalize on the ambient vibrations surrounding a system is one method that has seen a dramatic rise in use for power harvesting. The simplicity associated with the piezoelectric micro-generators makes it very attractive for Micro Electro Mechanical Systems (MEMS) applications, in which mechanical vibrations are harvested and converted to electric energy, these micro-generators were designed as an alternative to a battery-based solution especially for remote systems. In this paper we proposed a design and simulation of MEMS-based energy harvested by using ANSYS11 and COVENTORWARE2008 approaches. The improvements in experimental results obtained in the vibration based MEMS piezoelectric energy harvesters show very good scope for MEMS piezoelectric harvesters in the fields of power MEMS and Green Technology in the near future.

Vibration energy harvesting is one of potential renewable energy that may replace conventional chemical battery as energy source for powering wireless micro-system. One of the vibration energy harvester designs makes use of Faraday's law of induction which is electromagnetic method. This type micro-generator generally consists of cantilever, magnets and coils. The generator uses two magnets arranged on the top and bottom at the end of cantilever while another end is fixed. The coils are placed beside two sides of the magnets. This paper presents an analysis of the cantilever by varying the physical dimension of the cantilever such as length, thickness and width. The analysis includes the resonant frequency of the cantilever and also the deflection under damping ratio. There is small difference between ANSYS simulation and theoretical calculation, which is about 1.4%. The adjustment of the length of cantilever provides the largest range of tuning frequency among the above mention parameters.

The rapid development nowadays contributes to unbalance of natural ecological system which leads to changes of earth climates and natural resources such as fresh water quality. Limitation of human resource to do real-time monitoring and data collection regarding this environmental issue will lead a major problem to fresh water supplies at coming decades. This paper describes an approach of Wireless Sensor Network (WSN) application to do real-time data collection at the fresh water resources such as rivers, lakes or wetlands areas to obtain proper water quality parameters measuring. The WSN system is used as a platform to monitor the fresh water quality readings, deployed at distributed location which each nodes will able to interface with various water quality sensors. The system will use a green power source via harvesting the solar day light with optimized power management to enhance the long life operation at remote rural areas. Then, the collected data from each node will go to sub-base station as the device network coordinator and to the monitoring station server via GSM network. This system powered by PIC16F886 nano-watt MCU, with RF XBEE 802.15.4, ISM 2.4 Ghz module for each node while the Coordinator device integrated with GSM/GPRS modem and monitoring LCD.

This paper proposed the design of a switchable dual-band low-noise amplifier (LNA) using Silterra 0.18-μm CMOS technology fabrication process. The LNA utilized the single-ended type with cascode inductively source degeneration topology. This topology is best for simultaneous noise and input matching besides capable of reducing the Miller effect as well as improving on the reverse isolation performance. The switchable dual-band LNA can be tuned to center frequency of either 1.575 GHz for global positioning system (GPS) or 2.4 GHz for WLAN 802.11b standard applications. The LNA can cater frequency range of 1.33 to 2.10 GHz and 1.69 to 2.64 GHz for GPS and WLAN application, respectively. The switching of the operating frequency can be achieved by capacitor selection using MOS as switches at its input and output matching network. NMOS switches were implemented as they have lower on resistance and can provide larger gain when compared with PMOS. The selection of the switches is based on the voltage supplied to each switch. The supply voltage for the LNA is 1.8 V and the voltage required to enable the MOS switches is 3 V. Pre-layout simulation for input third-order intercept points (IIP3) are +1.62 dBm and +1.17 dBm for center frequency of 1.575 GHz and 2.4 GHz, respectively. Post layout simulation shows input reflection coefficients (S 11 ) of −15 dB and −16 dB, reverse isolation coefficients (S 12 ) of −56 dB and −50 dB, power gains (S 21 ) of 10 dB and 11 dB, output reflection coefficients (S 22 ) of −13 dB and −15 dB and noise figure (NF) of 3.2 dB and 3 dB for center frequency of 1.575 GHz and 2.4 GHz, respectively. Thus, the design is able to meet the requirements of the desired standards. The LNA consumes current of 18.5 mA at both 1.575 GHz and 2.4 GHz frequencies and therefore resulting a power consumption of 33.23 mW.

This paper presents a scalable host controller for modular hardware accelerator. Designing a hardware method of scalable host controller can handle multiple processing units at the same time. Currently in System on Chip (SoC) design, multiple processing units accessing the memory to request a task lead to inefficient communications due to bus congestion. In addition, designing a scalable host controller helps the transactions schedule consistently between different processing units in the modular hardware accelerator. In this paper, the hardware approach of scalable host controller design is expected to support up to seven different processing units.

Convective accelerometer does not contain seismic mass and work based on free convection heat transfer of electrical heater inside a hermetic chamber. Its sensitivity is dependent to the temperature distribution of working fluid inside the hermetic chamber. In this paper, the effect of working fluid properties, acceleration and heater power on temperature profile inside the convective accelerometer hermetic chamber is presented. Convective accelerometers with various working fluids (air, carbon dioxide, water, nitrogen, argon, helium, and ethylene glycol), heater powers (0.1 to 1.0 watts), and accelerations (1 to 5 g) were simulated by using ConventorWare 2010 software. Result shows, without acceleration the temperature profile of working fluid is symmetry around the vertical axis in relation to the heat source while with acceleration, the temperature profile is slightly skewed towards the acceleration direction. Argon is the best candidate for working fluid because it produces the largest temperature difference between the left and the right sides of the heater which would result in high sensitivity accelerometer. Convective accelerometer sensitivity also can be enhanced by increasing heater power, using gas-phase working fluids and locating the temperature sensors in the range between 100 to 300 μm away from the heater.

This paper is to study the characteristics of nanowire-CMOS and effect of increasing of numbers of nanowires in transistors on the nanowire-CMOS characteristics. This study used MuGFET simulation tool to produce the characteristics of nanowire transistors and used as input to MATLAB software to produce the characteristics of nanowire-CMOS. Increasing channel nanowires in P-channel transistor tends to improve the transfer characteristics of CMOS. Increasing channel nanowires in N-channel transistor tends to poorer transfer characteristics of CMOS.

The design and simulation of an MEMS-based capacitive bending strain sensor using silicone dope as a plate is presented in this paper. The objective is to design and simulate the performance of a strain sensor using a dielectric material between capacitive plates. The silicone dioxide (SiO 2 ) and polydimethylsiloxane (PDMS) was utilized as the dielectric layer in this model. Several dimensions of the sensor and the dielectric materials were studied as silicon dioxide was also used to increase the performance of the sensor. The application of the sensor is for the spinal fusion monitoring system. The finite element analysis (FEA) was performed using MEMS CoventorWare 2008, and the results were verified using the analytical method. Based on simulation results, the presences of the dielectric material has increased the capacitance output of the sensors and produced greater sensitivity. The sensitivity of the sensor is 24.9–44.48% higher compared with existing sensors. The nominal capacitance of the sensor also improved significantly from 94.16pF to 156.14pF. The sensor also exhibits greater sensitivity at the early stage of the bending strain; the sensitivity of the sensor is up to 0.525pF/μe.

Temperature uniformity on a micro-hotplate is important for gas sensor sensitivity, linearity, and resolution. There are several ways to create a uniform temperature distribution on a micro-hotplate. In this paper, the modification of microheater geometry is the method used. Four different heater geometries are simulated using ConvetorWare software to determine which geometry can give the most uniform temperature distribution. The simulations show that the heater geometry which combines parallel and meander shapes results in the most uniform heat distribution. The electrical potential and current distributions of the four different micro-heater geometries are also evaluated.

Energy scavenging from ambient sources is an attractive alternative to batteries because of an almost unlimited lifetime and is environmentally safe. Environmental vibration is a particularly attractive energy source because of its abundance, and several scavenging techniques such as piezoelectric, electrostatic and electromagnetic (EM) transduction. Since it is quite easy to keep a strong magnetic field with a permanent magnet, electromagnetic vibration-power generators are preferred in many applications. This paper presents a comparative study of electromagnetic generator via Finite Element Analysis (FEA). It involves the investigation of the magnetic behaviours for several configurations of electromagnetic generator. The configuration varies in terms of types of magnet and the arrangement of the magnet. Finite element models are developed and further analyzed via ANSYS software. Analyses are conducted prior to investigate the magnetic behaviours of the electromagnetic generator such as the flux lines, the magnetic flux density and also the electromotive force (emf) produced.

The effect of material, thickness and the magnitude of heat generated by microcombustor on heat distribution along thermal spreader for thermoelectric power generator are investigated. Impact of various materials and physical properties was studied upon sample 3 cm × 3 cm. The effect of thermal conductivity, specific heat capacity and thickness towards temperature uniformity of thermal spreader is observed. The result provides temperature profile of the thermal spreader dependencies of the source of heat. Results show that copper is the best thermal spreader material for thermoelectric power generator.

The micro power generation using vibration energy sources appears to be attractive due to its applicability on many situations and environmental conditions. The electrostatic energy harvester has various advantageous over piezoelectric and electromagnetic systems such as reduction in fabrication process complexity and cost, feasibility on MEMS and IC integration, improves the possibility level of integration with silicon based microelectronics and produce voltage within the usable range which can obviating the need of large and expensive generator. This paper presents the design and simulation of SOI-MEMS electrostatic vibration energy harvester using the architect module in CoventorWare2010. Simulation results shows that the newly proposed electrostatic energy harvesting system can produce maximum output power of 5.891µW when the excitation frequency is 2 kHz.

This chapter presents an adaptive Multicarrier Frequency Hopping Spread Spectrum (MCFH-SS) system employing proposed Quasi Cyclic Low Density Parity Check (QC-LDPC) codes instead of the conventional LDPC codes. A new technique for constructing the QC-LDPC codes based on row division method is proposed. The new codes offer more flexibility in terms of girth, code rates and codeword length. Moreover, a new scheme for channel prediction in MCFH-SS system is also proposed. The technique adaptively estimates the channel conditions and eliminates the need for the system to transmit a request message prior to transmitting the packet data. The proposed adaptive MCFH-SS system uses PN sequences to spread out frequency spectrum, reduce the power spectral density and minimize the jammer effects.

Fiber optic sensors are being extensively developed and utilized in various fields, compared to conventional sensing technologies, due to their exclusive properties, such as complete immunity to electromagnetic interference, capability of functioning in hostile surroundings, elevated sensitivity and user-friendliness. The unique characteristics of fiber optic sensors can provide more accurate and precise detection of crack damage in concrete structures, the deterioration of which is one of the major growing problems worldwide. This paper provides a comprehensive critical review and comparison of various approaches used in detecting crack damage using fiber optic sensors. A separate section is devoted to highlight the areas where further improvements are required. The compatibility and sustainability of the latest fiber optic sensors in detecting concrete damage are also studied and evaluated in this paper.

The wireless sensor network (WSN) market is growing quickly yet is limited by existing short lifetime batteries. Providing a green, virtually infinite alternative power source to traditional energy sources will significantly expand applications for WSNs and other technologies, the use of piezoelectric materials to capitalize on the ambient vibrations surrounding a system is one method that has seen a dramatic rise in use for power harvesting. The simplicity associated with the piezoelectric micro-generators makes it very attractive for MEMS applications, in which mechanical vibrations are harvested and converted to electric energy, these micro-generators were designed as an alternative to a battery-based solution especially for remote systems. In this paper we reviewed the work carried out by researchers during the last two years. The improvements in experimental results obtained in the vibration based MEMS piezoelectric energy harvesters show very good scope for MEMS piezoelectric harvesters in the fields of power MEMS and Green Technology in the near future.

This work presents a new scheme for channel prediction in multicarrier frequency hopping spread spectrum (MCFH-SS) system. The technique adaptively estimates the channel conditions and eliminates the need for the system to transmit a request message prior to transmit the packet data. The new adaptive MCFH-SS system employs the Quasi-Cyclic low density parity check (QC-LDPC) codes instead of the regular conventional LDPC codes. In this work performance of the proposed MCFH-SS system with adaptive channel prediction scheme is compared with the fast frequency hopping spread spectrum (FFH-SS) system. The proposed system has full control of that spectrum; it plans for the system to keep off unacceptable adjacent channel interference. When an interferer suddenly changes its carrier, the set of appropriate channels has a large return and resultantly the adjacent channel interference between the systems is reduced. It has been shown from results that the signal power in FFH system exceeds the average by at least 6.54 dB while in the proposed MCFH-SS system signal power exceeds the average only 0.84 dB for 1% (correct use) of the time. The proposed MCFH-SS system is more robust to narrow band interference and multipath fading than the FFH-SS system, because such system requires more perfect autocorrelation function.

Accelerated advancement in the field of System-on-Chip necessitates solving the bus contention in a most efficient manner. In any real time computing system, the major challenge is to reduce the latency of the system and to achieve a fair bandwidth allocation. Implanting processors according to their traffic behavior on to the Adaptive Arbitration architecture can be one of the feasible options to tackle the aforesaid problems to a remarkable extent. This combination of Adaptive Arbitration and the processors according to their traffic behavior has interesting advantages compared with other conventional arbiters due to its fair bandwidth allotment and low system latency. This article provides a comprehensive picture of the global scenario of Adaptive Arbitration algorithm for fair bandwidth allocation so as to enable researchers to decide the direction of further investigation. Some of the works published so far in this area are reviewed, classified according to their objectives and presented in an organized manner with a final conclusion.

This paper discusses about power management in wireless sensor network application. Energy harvesting concept must be applied in order to avoid high maintenance to change the battery frequently. In energy harvesting concept, solar energy can be used to charge the battery that supplied power to the whole system. Boost converter is also important in order to get a constant voltage from battery. MAX773 is used as a boost converter in this application. Results show that the device can be integrated to temperature sensor with 70% efficiency.

A novel fabrication technique using polymethylmethacrylate (PMMA) as a base material for SU8-10 film coating is to be discussed in this paper. The SU8-10 coated onto PMMA is used as a mold to fabricate PDMS relief. The SU8-10 mold has been tested for a square structure and various types of line resolutions. Propylene Glycol Methyl Ether Acetate (PGMEA) developing towards SU8-10 coated on PMMA for 2 hours is suitable for a 5mm × 5mm square structure whereas PGMEA developing for 30 minutes is found to be suitable to produce the smallest resolution of 2mm. The results have proven that PMMA is a promising material to be used as SU8-10 mold despite silicon or glass, two materials which have been commonly used for SU8-10 mold. PMMA in its natural structure is flexible, making it easy to drill and cut. Other advantages of PMMA lie in the facts that it is cheap, transparent and biocompatible.

A simple fabrication method on wet etching and thermal evaporator had been used to fabricate microfluidic three gold (Au) electrodes assembled with polydimethylsiloxane (PDMS) was reported in the present work. In this work, we studied the suitable size of electrode area that can fulfill the Randle-Sevcik equation for reversible redox process. The voltammograms of 0.01 M K 3 Fe(CN) 6 in 0.1M KCl at 1.04 mm2 electrode area demonstrates the current peak ratio of unity thus suitable to be further developed as a three electrode sensory system with Ag/AgCl reference electrode. The plotted graph for peak current vs electrode area satisfied the Randle-Sevcik equation as well. Cyclic Voltammetry (CV) analysis proved that the fabricated sensor was reliable in the range of 24 hours at the room temperature of 25°C.

This paper presents a comprehensive survey on vibration powered electromagnetic micro generator, which harvest mechanical energy from environment and convert this energy into useful electrical power for micro system and sensor node. The on-going research works on electromagnetic micro generator are reviewed as a background of this paper. Basic theories of micro generator to produce power from ambient motion by damping the suspended proof mass system over the coils are presented. Several important parameters such as the shape, types of magnet, spring and coil property used in designing electromagnetic micro generator as well as power processing circuit are also included. Different designs of micro generator for different environment and application are discussed. Significant challenges in converting the power by each design are also highlighted in this paper.

Microthermophotovoltaic (micro-TPV) systems are generators currently being extensively developed to convert radiation heat energy from hydrocarbon fuel combustion into useful electricity by using low band-gap photovoltaic cell for microelectromechanical systems (MEMS). Micro-TPV systems consist of a heat source (microcombustor), a thermal emitter (microcombustor surfaces), a dielectric/optical filter, and photovoltaic cells. The architecture of a micro-TPV system and its components are currently the focus of research aiming to improve the overall system architecture, efficiency, and performance for practical implementation in the MEMS industry.

Sulfate reducing bacteria (SRB) is a nonpathogenic and anaerobic bacterium which can produce enzyme to accelerate the reduction of sulfate compounds to hydrogen sulphate that corrodes metal. This paper will study the possibility of using electronic nose which consists of chemical sensing system, data acquisition system and pattern recognition system such as artificial neural network to detect hydrogen sulphide. There are a few methods of detecting SRB such as laboratory analysis and field test kit but the procedures are costly and take longer time, within 1 to 2 days. Study shows that electronic nose can be used to detect SRB by detecting hydrogen sulphide that is produced during reduction process. The electronic nose can detect hydrogen sulphide within 16 hours where the detection period is reduced from 30% to 65%. Study also shows that the electronic nose with micro hotplate sensor base will reduce 86% of power consumption compared to electronic nose with alumina ceramic sensor base.

CRC (Cyclic Redundancy Check) block was developed on FPGA (Field Programmable Gate Array) in order to meet the needs for simple, low-power and low-cost wireless communication such as Zigbee. Zigbee operates primarily in the 2.4 GHz band, which makes the technology easily applicable and worldwide available. This paper gives a short overview of CRC block in the digital transmitter based on Zigbee Standard. The purpose of the research is to diversify the design methods by using the Verilog code entry through Xilinx ISE 8.2i. Here, the simulation and measurement results are also presented to verify the functionality of the CRC block. The data rate of CRC block is 250 kbps.

This paper proposes a new technique for constructing the Quasi-Cyclic low density parity check (QC-LDPC) codes based on row division method. The new codes offer more flexibility in term of girth, code rates and codeword length. In this method of code construction, the rows are used to form as the distance graph. Then they are transformed to a parity-check matrix in order to acquire the desired girth. The new QC-LDPC codes show good bit-error rate performance as compared to the renowned Mackay codes for given values of E b /N o by 0.12 dB at BER of10-7 .

In this paper, we proposed a sealing technique for a sealing glass cap with a ceramic substrate by using silica coating liquid to increase the performance of fluid-based inclination sensor in heat-resisting and durability characteristic. The sensor was developed with one-side-electrode-type structure and propylene carbonate was used as electrolyte. The sensor uses capacitance change to detect the angle of inclination, and it is capable measuring inclination at supply voltage 1.5 V. The diameter of glass cap and height were 4.0 mm and 2.0 mm, respectively. The linearity of characteristic can be improved when the supply voltage was set at 1.5 V. The sensitivity, response time and resolution of sensor were 4 mV/deg, 0.6 s and 1.8 deg, respectively at the supply voltage 1.5 V. The temperature characteristic was evaluated between −10 °C to 50 °C.

This study presents the behavior of a micro cantilever beam accelerometer under electrostatic actuation by using the analytical and numerical method. The objective of this study is to determine optimal design of capacitive micro cantilever beam accelerometer in term of reducing the beam deflection with respect to applied acceleration but keeping the distance between electrodes. The structure contains proof mass which is suspended between fixed rigid electrodes to provide differential capacitance measurements. ANSYSO is used for finite element analysis (FEA) modeling and simulation. The analytical modeling is done by using C programming. Three dimensional modeling is done for six different loading conditions in order to come out with the optimal design. The results obtained from both the analytical and finite element models are found to be in excellent agreement.

To cut down the hardware implementation cost this paper presents an efficient method to construct large girth Quasi-Cyclic low density parity check (QC-LDPC) codes. The row groups are paired two times the row weight, which has the complexity as compared to the connection of individual columns and rows. The complexity of directing within groups estimates on the transposition employed to connect rows and columns between groups. The newly obtained codes are incorporated with diversity techniques and are employed as a forward error correction codes to cater for some anti-jamming (AJ) competences in the presence of partial band noise jamming (PBNJ). The robustness of two girth-twelve QC-LDPC codes is evidenced by comparing it with randomly constructed LDPC codes and QC-LDPC codes proposed in [14].

The purpose of this paper is to present the analysis of electrostatic actuated microrelay with four terminals, single-pole, single-throw, and normally-open device with bridge contact (SPST-NO-Bridge) via simple analytical modeling and Finite Element Method (FEM). The behavior of the device has been simulated using electrostatic, mechanical and dynamic analysis. The results obtained by FEM and analytical analysis are in good agreement. Through optimization process of the physical structure, the total size of the device (without bondpads) is about 220 x 220 µm2, which is suitable for high integration circuitry. The results shows that minimum switching voltage is 17V with operating voltage of 24V and the device can go up to 2 KHz of switching frequency.

Digital transmitter was developed on FPGA (Field Programmable Gate Array) in order to meet the needs for simple, low-power and low-cost wireless communication such as Zigbee. Zigbee operates primarily in the 2.4 GHz band, which makes the technology easily applicable and worldwide available. However, this paper only covers the bit-to-symbol block and the symbol-to-chip block of the digital transmitter for an acknowledgment frame. These two blocks are combined together as bit-to-chip block before implemented on Spartan3E XC3S500E FPGA. The purpose of the research is to diversify the design methods by using the Verilog code entry through Xilinx ISE 8.2i. Here, the simulation and measurement results are also presented to verify the functionality of the combined block. The frequency for input data and output data are 250 kHz and 2 MHz respectively.

DOE (design of experiment) with simulation approach is presented that allow early visibility, guidance, and analysis of clamp placement in early design stage (power template design) on a chip level complexity. ESD robustness of product is largely attributed to the degree of correct implementation of ESD design rules in a highly complex design. Correct clamp placements is one of the most difficult and less guidance. Therefore, a 'reliable' & 'comprehensive' ESD clamp placement analysis is urgently needed. This simulation would deliver a preliminary guidance of clamp placement. It provides the information of where the most probable clamp placement is in the particular power template design. Since it takes into consideration the ESD ohm rules requirements during the construction of ohm sector, it would have a very high confident level that the design would not encounter much issue in the ESD resistance checkout later. Apart from the ESD design rules checkout, we also couple with TLP (transient line pulse) testing which has proven this approach could deliver a promising ESD protection robustness. We can characterize, co-relate, and compare our simulation with the Si data from various design perspectives. All in all, the real strength of this simulation is the ability to provide earlier design guidance & optimization options starting from the product concept phase (power template design stage), which allows to align ESD with all design issues on a cost and time efficient way. Without the simulation, designer would need to manually calculate the resistance , rely on past experience and some assumption with nil data support which is tedious & error prone for complex design nowadays. This allows ESD design rules compliance in the early design stage, thus enhancing the approach of "correct-by-construction" on ESD design.

In this paper, we proposed a new physical-based equation to model the CMOS transistor STI y-stress (in the direction of channel width). It can be used in any SPICE MOS model and it has been verified on 0.13 um CMOS transistors. The physical characteristics of the compressive STI y-stress effect on saturation drain current, Idsat are captured by using a new proposed transistor layout method. The equation that is able to describe the physical characteristics of the STI y-stress effect is incorporated into the electron and hole mobility, uO of the SPICE model to capture the y-stress effect on Idsat. With the combination of the new y-stress parameters and the default delta width parameters in the SPICE model, we are able to fit the simulation curve to the hook shaped Idsat curve from the actual silicon data.

In this paper we analyzed the mismatch characteristics of poly resistors. We found that the P+ poly resistor mismatch characteristics do not follow the linear inverse square root dependence. Instead, the P+ poly resistor mismatch follows the quadratic of inverse square root (or a simple inverse area) dependence. N+ poly resistor mismatch, however does obey the expected standard inverse square root dependence.

In this paper an integrated system is developed to detect shock vibration by using MEMS accelerometer. The interface circuit which converts the signal from an accelerometer capacitive element to a pulse signal for digital signal processing is built. Changes in the capacitance between fixed and movable plates are induced by acceleration from shock vibration. Interface circuit incorporating this capacitor then extracts the acceleration signal and converts it to digital or analog form using microcontroller microprocessor. GUI is developed to make the integration data system more interesting and user friendly. The sensing of MEMS and monitoring software are integrated together to provide real time acquire data and graphical visualization for monitoring, recording and analysis purposes.

In this paper, we propose a method that can measure the shallow trench isolation (STI) stress effect on transistor in the direction of channel width. Instead of implanting the entire channel (fixed width of 10um), we only implant one portion of the channel (with fixed implant opening width of 0.5um). By using this method, the channel edge can be brought away from the STI edge, where the active area is under high compressive stress. The results show that when the effective channel is near to the STI edge (high transverse compressive stress), both NMOS and PMOS transistors have higher threshold voltage, Vt and lower drain current, Id.

We investigate the 130nm (1.2V) and 280nm (2.5V) CMOS linear threshold voltage (Vtlin) and normalized saturation drain current (Idsat) versus channel width. Plots of Vtlin and Idsat versus channel width for different lengths are used to show the complex behavior as the channel width decreases. Both NMOS and PMOS Vtlin reach a maximum and then decrease as the width goes to W = 0.15/spl mu/m. NMOS Vtlin shows a 30% decease while PMOS Vtlin decreases 5% to 18%. We then show that the Vtlin behavior is caused by two opposite factors, shallow trench isolation (STI) y-stress effect and inverse narrow width (INW) effect. We eliminate x-stress as a factor by designing all the transistors with Sa = 10/spl mu/m. We observe that NMOS and PMOS Idsat decrease as the width decreases from 20/spl mu/m to 1/spl mu/m reaching a minimum, after that Idsat increases again. We believe this Idsat behavior is also caused by two opposite factors, STI y-stress effect and delta width, DW effect. The Idsat behavior is different for NMOS and PMOS. The STI y-stress effect is less pronounced for short channel NMOS transistors while the DW effect is weaker for short channel PMOS transistors.

In this paper, we proposed two new MOS compact model parameters (synuO and sypuO) to be added to the mobility parameter uO to model the mechanical shallow trench isolation (STI) y-stress. By using a layout experiment, we show that the STI y-stress causes the hook shaped Idsat versus width curve. We demonstrate that by introducing these new model parameters, we are able to fit the actual data more accurately. The STI y-stress effect is modeled by using the synuO parameter (for NMOS) and sypuO parameter (for PMOS) to control the fit to the hook shaped Idsat curve

In this paper, we investigated the compressive mechanical STI x-stress (in the direction of channel length) on channel width. When the channel width becomes narrower, the compressive STI y-stress effect become more severe and causes STI x-stress has lower effect on NMOS Idsat but has higher effect on PMOS Idsat. This means that the amount of NMOS Idsat decrement due to x-stress become less but the amount of PMOS Idsat increment due to x-stress become higher when y-stress increases (narrower channel width)