Oxygen plays a fundamental role in nature and industrial process,the fast on-line oxygen concentration detection is of great significance.Tunable diode laser absorption spectroscopy (TDLAS) is capable high selective,high sensitive,non-intrusive,this technique exploits the diode laser tunable and narrow bandwidth characteristics,by selecting one absorption line of the target gas to avoid interference from other gas and realize oxygen concentration fast on-line detection.In this paper,we use vertical cavity surface-emitting laser (VCSEL) as the light source,adopting the wavelength modulation spectroscopy and the harmonic detection technology to measure the second harmonic signal and realize oxygen concentration fast on-line detection.The detection concentration range between 0.1％ to 40％ and detection accuracy is 0.1％.

关键词：氧传感器；TDLAS；WMS VCSEL

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A new method of implementing frequency invariant beamformers based on cubic spline function is presented.Based on the frequency,the sensor distance of the virtual array is generated.The virtual array output is formed from the sensor array by cubic spline function interpolation.The beamformers of every frequency bins in the bandwidth of the signal is similar to that of the referenced frequency.The method is simple and easy to implement.Simulation results demonstrate the effectiveness of the method.

关键词：波束形成；阵列信号处理；宽带资源；三次样条函数

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关键词：发射器；射频；通信网络；探测器；全球定位系统

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The development of a novel and inexpensive sensor network for detecting the electrostatic field (ESF) of a charged bullet was explored in this paper. The principle method used to measure the ESF of the passing object was based on a voltage-controlled variable capacitance. This method utilized a varactor pair and sinusoidal input signal to produce a significant change in voltage proportional to the minute change in capacitance caused by the passing object's ESF. A wired network was used to propagate the measurements to a central data acquisition unit (DAQ). The DAQ processed the data from the senor array. The results from the DAQ report the passing objects coordinated in relation to the designated central location. This paper describes the sensors, and presents results using measured (live-fire) data.

关键词：传感器；检测；静电场

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Various RF circuit blocks implemented by using commercially available MEMS digital capacitor arrays are presented for reconfigurable RF systems. The designed circuit blocks are impedance-matching network, tunable bandpass filter, and VSWR sensor. The frequency range of the designed circuits is 0.4-4GHz. The MEMS digital capacitor arrays that are employed in the designs have built-in dc-to-dc voltage converter and serial interface significantly simplifying the control circuitry. The RF circuit blocks are suitable to low-cost, high-level of integration, thanks to the commercially available parts and standard RF packaging technologies.

关键词：电容器；微机电系统；带通滤波器；现场可编程门阵列

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The ability to conveniently and immediately test and diagnose in a diverse and rapidly changing environment is critical for field diagnostics. Smart biomedical sensors employ many different diagnostic/therapeutic methodologies; however, an ideal system would include the ability for results to be shared instantaneously with all members of the team through a software interface. We discuss our efforts towards the development and use of a robust, mobile platform (Android-based smart phone) that incorporates stable molecular recognition elements in sensor development. The inexpensive, compact, robust, archival, and portable design is ideal for rapid field diagnostics.

关键词：诊断(医学)；生物医学；计算机程序；配体；移动计算

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Accurate and efficient clock synchronization algorithm is very important in Wireless Sensor Networks (WSN).Considering the physical nature of sensors,a multi-model kalman filter clock synchronization algorithm based on experiments and hypothesis testing theory is proposed.The sensor experiments on the base of TelosB platform demonstrate that sensor clock system switches between different models.Based on this observation,a general multi-model kalman filter to describe clock offset is presented.Hypothesis testing method is used to switch the model between the first-order kalman filter and second-order kalman filter.Experiments show that the proposed algorithm can trace clock offset effectively.

关键词：传感器网络；多模型卡尔曼滤波器；假设检验；时钟偏移量

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Moore’s law has allowed the microprocessor market to innovate at an astonishing rate. We believe microchip implants are the next frontier for the integrated circuit industry. Current health monitoring technologies are large, expensive, and consume significant power. By miniaturizing and reducing power, monitoring equipment can be implanted into the body and allow 24/7 health monitoring. We plan to implement a new transmitter topology, compressed sensing, which can be used for wireless communications with microchip implants. This paper focuses on the ADC used in the compressed sensing signal chain. Using the Cadence suite of tools and a 32/28nm process, we produced simulations of our compressed sensing Analog to Digital Converter to feed into a Digital Compression circuit. Our results indicate that a 12-bit, 20Ksample, 9.8nW Successive Approximation ADC is possible for diagnostic resolution (10 bits). By incorporating a hybrid-C2C DAC with differential floating voltage shields, it is possible to obtain 9.7 ENOB. Thus, we recommend this ADC for use in compressed sensing for biomedical purposes. Not only will it be useful in digital compressed sensing, but this can also be repurposed for use in analog compressed sensing.

关键词：压缩感知;摩尔定律;微芯片植入;集成电路;微处理器

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Minimization of energy consumption is one of the most important research areas in Wireless Sensor Networks.Nowadays,the paradigms of computational intelligence (CI) are widely used in WSN,such as localization,clustering,energy aware routing,task scheduling,security,etc.Though many fuzzy based clustering techniques have been proposed earlier,many of them could not increase the total network life time in terms of LND (Last Node Dies) with comparing to LEACH.In this paper,a fuzzy logic based energy-aware dynamic clustering technique is proposed,which increases the network lifetime in terms of LND.Here,two inputs are given in the fuzzy inference system and a node is selected as a cluster head according to the fuzzy cost (output).The main advantage of this protocol is that the optimum number of cluster is formed in every round,which is almost impossible in LEACH (low-energy adaptive clustering hierarchy).Moreover,this protocol has less computational load and complexity.The simulation result demonstrates that this approach performs better than LEACH in terms of energy saving as well as network lifetime.

关键词：传感器网络；模糊逻辑；网络寿命；集群

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Foliage Penetration (FOPEN) radars are critical for detecting and identifying targets concealed by trees and forests. Typically, FOPEN transmits at high powers, making them difficult to design and operate at low frequencies where mismatches are possible. Low operating frequencies also result in large apertures that limit FOPEN systems to large platforms. Novel metamaterials have the potential to reduce the size of FOPEN antennas, but two persistent challenges remain. First, high transmit power requires a low-loss metamaterial solution. Second, the wide bandwidth required by FOPEN systems makes resonant metamaterials solutions unworkable. To shrink the volume of state-of-the-art FOPEN antennas and create a new capability for volume-limited aircraft, Lockheed Martin (LM) Corporation, in conjunction with the Ohio State University (OSU), proposes to develop a novel, metamaterial FOPEN antenna. Shadow Harvest, currently a USAF/ACC JCTD, is a sensor pod and roll-on/roll-off analyst module that adds ISR capability to any C-130 in the USAF fleet within 24 hours.

关键词：雷达；天线阵列；光束控制；高功率；低频率

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