Design and implementation of a hybrid circuit system for micro sensor signal processing

This paper covers a micro sensor analog signal processing circuit system(MASPS) chip with low power and a digital signal processing circuit board implementation including hardware connection and software design. Attention has been paid to incorporate the MASPS chip into the digital circuit board.The ultimate aim is to form a hybrid circuit used for mixed-signal processing,which can be applied to a micro sensor flow monitoring system.     

A low-power RF integrated circuit for implantable sensors

A low-power low-voltage analog signal processing circuit has been designed, fabricated, and tested. The circuit is capable of processing an analog sensor current and producing an ASK modulated digital signal with modulating signal frequency proportional to the sensor current level. An on-chip regulator has been included to stabilize the supply voltage received from an external RF power source. The circuit can operate with a power supply as low as 1 V and consumes only about 20 μW of power, which is therefore very suitable for implantable biomedical applications. The whole chip was laid out and fabricated in a 0.35 μm bulk CMOS technology. Experimental results show good agreement with the simulation results.     

A Versatile High-speed Image Processing System Based on DSP and CPLD

In this paper, we present an optimized design method for high-speed embedded image processing system using 32 bit floating-point Digital Signal Processor （DSP） and Complex Programmable Logic Device （CPLD）. The DSP acts as the main processor of the system： executes digital image processing algorithms and operates other devices such as image sensor and CPLD. The CPLD is used to acquire images and achieve complex logic control of the whole system. Some key technologies are introduced to enhance the performance of our system. In particular, the use of DSP/BIOS tool to develop DSP applications makes our program run much more efficiently. As a result, this system can provide an excellent computing platform not only for executing complex image processing algorithms, but also for other digital signal processing or multi-channel data collection by choosing different sensors or Analog-to-Digital （A/D） converters.     

Infrared Real—time Thermal System Based on DSP

An infrared real-time imaging system using DSP(digital signal processor)as the kernel of digital signal processing board is presented.In this system,the imaging difference and nonuniformity correction method is developed on the chip taking advantage of DSP with high speed.The method combines hardware and software together,so that the difficulty for realizing such a method with other hardware can be overcome.     

RS trigger based relaxation oscillator for temperature measurement circuit

Resistance-to-time converter is always used for digital temperature measurement. An reset-set （RS） trigger based, relaxation oscillator based temperature measurement circuit, which is used to convert the change of thermistor sensor into a frequency signal for later processing, has been presented in this article. The RS trigger, which is composed of two inverters designed with distinct logical transition threshold voltages by changing the metal-oxide-semiconductor （MOS） transistor gains, has the same function as the Schmitt trigger in the relaxation oscillator. The advantage of the RS trigger based Schmitt trigger is that it reduces the dependence to supply voltage, chip temperature, and process variation. This temperature measurement circuit has been applied in a clinical thermometer chip that can measure temperature to an accuracy of better than 0.05 ℃ down to 1.1 V battery voltage. It is fabricated in 0.5 μm double metal single poly complementary MOS （CMOS） process.     

Design and implementation of the optical fiber control and transmission module in multi-channel broadband digital receiver

An optical fiber control and transmission module is designed and realized based on Virtex-7 field programmable gata array （FPGA）, which can be applied in multi-channel broadband digital receivers. The module consists of sampling data transfer submodule and multi-channel synchronous sampling control submodule. The sampling data transmission in 4× fiber link channel is realized with the self-defined transfer protocol. The measured maximum data rate is 4.97 Gbyte/s. By connecting coherent clocks to the transmitter and receiver endpoints and using the self-defined transfer protocol, multi-channel sampling control signals transferred in optical fibers can be received synchronously by each analog-to-digital converter （ADC） with high accuracy and strong anti-interference ability. The module designed in this paper has certain reference value in increasing the transmission bandwidth and the synchronous sampling accuracy of multi-channel broadband digital receivers.     

Underwater Optical Fiber Fluorescent System for Measuring Chlorophyll—a Concentration

Using optical fiber fluorescent technology, a new method for measuring alga concentration in water is presented.The system can realize on-line measurement for alga concentration using He-Ne laser as the light source.It can also effectively detect weak signals.The system with a passive sensor head has such advantages as simple structure, high sensitivity and high accuracy.It has been demonstrated that this system can be used to monitor water quality and can also be used to survey some matter.     

Tunable microwave photonic filter based on a fiber ring and erbium-doped fiber amplifier

The tunable microwave photonic filter based on a fiber ring and erbium-doped fiber amplifier （EDFA） was proposed. By introducing a section of erbium-doped fiber （EDF） into the fiber ring, the loss of the signal can be compensated by the EDFA gain through adjusting the pump power. This can largely increase the number of the effective sampling taps, and then improve the performance of the microwave photonic filter notably. When the pump power was set to be 42.7 roW, a microwave bandpass filter with the 3-dB bandwidth of 0.15 MHz, the Q factor up to 100 and extinction ratio up to 20 dB was achieved. By employing a tunable optical delay line in the above fiber ring, a tunable microwave photonic filter has been realized through tuning the length of the optical delay line. The proposed tunable microwave photonic filter can fred great applications in microwave signal processing and ROF system.     

A special issue on photonic signal processing

Photonic signal processing has been receiving increasing attention for about fifteen years.It would be enabling technology for next generation large capacity optical networks because it can avoid electronics bottleneck and decrease power consumption greatly.There are two main areas related to photonic signal processing.One topic is all-optical signal processing for digital bit sequence in optical network,such as all-optical wavelength conversion,alloptical logic operation,all-optical 3R regeneration,all-optical clock recovery,all-optical buffer,etc.The other topic is microwave photonic signal processing,such as microwave photonic filters,arbitrary waveform generation,RF signal generation,UWB signal generation,etc.However,there are still many problems to be solved before these functions could be used in optical networks.Researchers all over the world are concentrating on realizing photonic signal processing functions with some characteristics such as high operation speed and large bandwidth,flexible and multifunctional,potential integration.     

Distributed Optical Fiber Sensor for Multi-point Temperature Measurement

The distributed optical fiber sensing technology is overviewed, which is based on Raman scattering light theory. Basic operation principle, structure, system characteristics and signal processing are discussed. This structure and method of the signal processing possess of certain spatial resolution, hence will ensure the practicability of system.     

一种基于光纤传输的监测信号处理系统

为了解决高压监测系统中的实时监测问题,设计了一种光纤传输的监测信号处理系统,监测信号通过高速模数转换变成数字信号后,通过光发射模块变成光数字信号,用光纤作为传输通道,传到目的地后再由光接收模拟把数字光信号变换成数字电信号,经过数模转换后恢复成模拟的监测信号。经过模拟验证后发现这个系统具有实时性强、失真小、系统体积小、抗干扰能力强等优点。     

任意中频带通信号多相数字下变频方法

基于多相结构的数字下变频方法由于其可实现性强。抗干扰能力强等优点。在电子系统软件化的趋势中得到越来越多的重视．其缺点是存在信号接收盲区．该文在多相滤波数字下变频方法的基础之上。提出了一种改进方法．该方法在不改变原有下变频器结构的前提下，实现监视带内任意中频位置带通信号接收，消除接收盲区。     

基于典范相关分析的雷达抗干扰技术研究

如何提高雷达的抗干扰能力一直是雷达信号处理的一大问题，问题的解决可以使雷达的检测和跟踪能力得以提高。在日趋复杂的信号环境下，传统信号处理方法的局限性愈来愈大。文中通过对雷达信号处理过程和典范相关分析技术的分析研究，提出采用基于典范相关分析的多步处理抗干扰方法进行雷达抗干扰信号处理，可使雷达在复杂背景下具有更强的抗干扰能力。仿真试验结果证明这种新的雷达抗干扰处理方法是可行和令人满意的。     

雷达图像传输系统的研制

本文介绍了雷达图像传输系统的基本组成、工作原理、关键技术及实现途径。该系统采用数字图像信息压缩/解压、扩频通信及EDA设计等技术,实现了雷达图像的双向传输,同时具有全双工数据通信和话音通信能力,并具备可靠性高、维修性好、通用性及抗干扰能力强等特点。     

基于FPGA的视频与通讯数据融合设计

为实现将时间值、方位值等串口通讯信息叠加进数字视频图像信号的某一固定行中,设计了基于FPGA的通讯数据与数字视频数据的融合系统。采用FPGA程序设计实现串行数据接收与内置FIFO处理,并提取视频数据的某一固定行,进行数据融合,使得通讯数据和视频数据在场信号有效下组合输出。基于FPGA的通讯数据与数字视频数据的融合系统实现了通讯数据与视频数据的融合,试验中通讯数据波特率为230.4kbit/s,视频信号帧频50 Hz,视频数据与通讯数据帧频相同,图像像素为1 024×1 024,通讯数据正确的融合入一场图像的最后一行中,系统工作稳定,工作状态良好。基于FPGA的通讯数据与数字视频数据的融合系统以最简硬件系统实现了通讯数据与数字视频数据的组合输出,满足图像处理及显示系统的要求,具有广泛的工程意义。     

光纤通信的保密抗干扰问题分析

光纤通信系统中使用的光波波长很短,频率很高,传输频带很宽,在保密方面性能好,在抗干扰方面能力强,而且便于采用数字通信方式。采用数字通信后,可以对数字信号实施数字加密,使窃听难度增加。对于本土作战的通信保障,光纤通信无疑是一种最安全、最可靠的保密抗干扰通信手段。     

随机线性调频步进雷达波形设计及成像算法研究

线性调频步进信号能在不增加系统瞬时带宽的情况下用数字信号处理的方法获得高的距离像分辨率,是一种高效的雷达信号形式.针对传统的线性调频步进信号抗干扰能力较差的问题,该文提出一种可以随机发射线性调频步进信号子脉冲的波形设计方法,结合压缩感知理论,运用较少的子脉冲实现了对运动目标1维距离像的重构和高分辨的2维成像.在此基础上...     

一种基于盲源分离的雷达抗干扰技术

如何提高雷达的抗干扰能力一直是雷达信号处理的一大问题，问题的解决可以使雷达的检测和跟踪能力得以提高。在日趋复杂的信号环境下，传统的信号处理方法的局限性愈来愈大。本文通过对雷达信号处理过程和盲源分离技术的分析研究，提出采用基于盲源分离的多步处理抗干扰方法进行雷达抗干扰信号处理，可使雷达在复杂背景下具有更强的抗干扰能力。仿真试验结果证明这种新的雷达抗干扰处理方法是可行和令人满意的。     

三分量全光纤加速度地震检波器的设计

本文介绍了顺变柱体型三分量全光纤加速度地震检波器。该检波器由1个质量量块，6个顺变柱体，3套迈克尔逊干涉仪光路组成。其单一轴向的加速度可达10^3rad/g（其中，g为重力加速度），可同时检测3个轴向的加速度ax、ay、az，矢量合成得空间加速度a，从而实现加速度的实时、高精度检测。     

基于DSP和CAN的高精度光电转换器研究

为了满足光纤液位测量系统的高精度和分布式控制需要,提出了一种基于数字信号处理器(DSP)和局域网控制器(CAN)的高精度光电转换器核心电路模块的设计方案,并进行了工程实现。从A/D数据采集电路、数字信号处理模块及CAN总线通信三方面阐述了光电转换器的工作原理,给出了软件处理流程。实验表明,该转换器简化了系统设计,具有精度高、数据传输稳定等特点,有良好的应用前景。