小型弹载遥测单元设计与实现

导弹系统要求弹载遥测单元在尽量小的空间中尽可能采集和传输最多的系统参数,以提高试验效率,减少系统研制成本。通过整合功能,减少了部件数量;通过采用大规模可编程器件和微封装器件,提高了性能体积比,在紧凑空间内,实现弹载遥测单元的全部功能。该弹载遥测单元已应用于某导弹飞行试验,实现模拟信号、数字信号和开关信号的实时采集和传输,试验数据完整准确。试验结果证明,遥测单元的设计可以满足系统的使用要求。     

From 8-1/3 bits/s to 100,000 bits/s in ten years

During the first 11 years of its planetary program, the United States sent seven spacecraft to explore the inner planets: Venus, Mars, and Mercury. At the beginning of this period, the telemetry data rate was 8-1/3 bits/s; by the end of the period it was 120 kbits/s, a more than ten-thousand-fold increase. To identify the major factors involved, the form of a deep space telemetry system is described and the values of the major factors for each of the seven spacecraft are given. The amount of the improvement in each is computed and the way in which the improvement was achieved is discussed. Finally, some possible directions for possible future improvements are suggested.     

多站遥测数据实时对接方法研究

针对目前使用的多站遥测数据实时处理模式,分析了其存在的弊端,在此基础上提出了遥测数据解密前进行多站遥测数据实时对接的设想,并研究了多站遥测数据实时对接方法的可行性和正确性。此方法采用理论弹道对遥测帧时间进行电波延迟修正,从而实现了按时间对齐遥测全帧的目的,并通过采用全帧检择的办法,对接形成了一个数据质量较好的遥测流。     

Micropower circuits for bidirectional wireless telemetry in neural recording applications

State-of-the art neural recording systems require electronics allowing for transcutaneous, bidirectional data transfer. As these circuits will be implanted near the brain, they must be small and low power. We have developed micropower integrated circuits for recovering clock and data signals over a transcutaneous power link. The data recovery circuit produces a digital data signal from an ac power waveform that has been amplitude modulated. We have also developed an FM transmitter with the lowest power dissipation reported for biosignal telemetry. The FM transmitter consists of a low-noise biopotential amplifier and a voltage controlled oscillator used to transmit amplified neural signals at a frequency near 433 MHz. All circuits were fabricated in a standard 0.5-microm CMOS VLSI process. The resulting chip is powered through a wireless inductive link. The power consumption of the clock and data recovery circuits is measured to be 129 microW; the power consumption of the transmitter is measured to be 465 microW when using an external surface mount inductor. Using a parasitic antenna less than 2 mm long, a received power level was measured to be -59.73 dBm at a distance of one meter.     

FY-2气象卫星信号的开发利用

详细介绍了基于风云二号静止气象卫星信号实现电离层闪烁监测、云图接收、太空环境参数接收的设备设计、构成。该设备主要用于实时监测分析风云二号卫星信号因电离层变化而造成的幅度闪烁和相位闪烁。由于静止卫星不存在运动所附带的变化,利用其稳定的L波段遥测信号来监测电离层闪烁,优越性显著。风云卫星展宽云图接收设备目前已遍布全国,该设备在其跟踪遥测及云图接收的基础上进行开发,易于组网监测。电离层闪烁监测的结果,将对空间的探测和通讯技术的发展具有重大的意义。     

一种软件无线电遥测信号产生系统

为了在遥测系统中产生多种调制模式的中频信号,进行了ICS-564A DAC卡应用程序开发,使其工作于连续正交转换模式,计算I,Q基带数据以及设置调制参数等,正确地产生了需要的信号,从而证明该系统具有可编程能力强、操作灵活的优点,能够满足使用需求。     

MicroBlaze软核处理器在遥测数据采集中的应用

介绍了32位软核处理器MicroBlaze的体系结构、开发工具和开发流程，以及它在遥测数据采集中的设计应用实例。仿真试验结果证明采用软核处理器的嵌入式遥测数据采集器达到了102．4kbps的码速率，能够正确采集信号，达到预定指标。     

基于PCM/PPK遥测体制的钟控序列加密方案及系统仿真

PCM/PPK telemetry system is a multinary pulse modulation system. It is commonly used to transmit high-accuracy time information and some express signals. To the issue of security that telemetry data is transmitted in the open space, a data encryption scheme in the PCM/PPK telemetry system is proposed. In this scheme, the PCM data of signal source are encrypted by stream cipher in which key streams are generated with clock control LSFR. The scheme can save system resource in the dual-modulation compound telemetry system. A backward key synchronization scheme is also proposed, which has the property of strong real-time and easy to implement. A simplified simulation model of PCM/PPK remote system is established based on the actual framework of telemetry system, and the model is simple and easy to simulate. The error performance of the system is analyzed in theory and tested by computer simulation. Also the security of the system is analyzed. The simulation and analysis results show that the encryption scheme can ensure the security of the telemetry data and does not cause error-diffusion.     

A CMOS integrated circuit for multichannel multiple-subjectbiotelemetry using bidirectional optical transmissions [weightlessnessin space effects application]

A CMOS integrated circuit for a noninvasive biological-signal telemetry system specified for use in medical and physiological studies of the influence of weightlessness in space is presented. The system can monitor multichannel (4 channels maximum) biological signals from multiple subjects (4 subjects maximum) in real time by using time multiplexing. A key technique so-called synchronized multiple-subject telemetry, to achieve multiple-subject telemetry has been proposed. This technique utilizes bidirectional optical transmissions with direct and scattered infrared lights between an observer and each of the subjects. An experimental CMOS IC to give a small light-weight low-power, and smart telemetry instrument for use on animals has been developed. This IC is for evaluating circuit blocks of the implantable monolithic telemetry instrument. The major circuit blocks include CMOS digital circuits for synchronization, subject selection and time multiplexing, analog circuits for pulse interval modulation, and other blocks such as a CMOS optical pulse receiver and an LED driver. A preliminary experimental multichannel telemetry from two subjects has been performed with the implemented IC chips, and the principal operation of the multiple-subject optical biotelemetry has been demonstrated     

Efficient data compression for seismic-while-drilling applications

Seismic-while-drilling services efficiently support drilling decisions. They use the vibrations produced by the drill-bit during perforation as a downhole seismic source. The seismic signal is recorded by sensors on the surface, and it is processed in order to obtain/update an image of the subsurface around the borehole. To improve the characterization of the source, some sensors have been experimentally installed also downhole, on the drill pipes in close proximity to the bit: data logged downhole have been able to give better quality information. Currently, the main drawback of downhole equipment is the absence of a high-bit-rate telemetry system to enable real-time activities. This problem may be solved by employing either an offline solution, with limited memory capacity up to few hundreds of megabytes, or an online solution with telemetry at a very low bit-rate (few bits per second). However, following the offline approach with standard acquisition parameters, the internal storage memory would be filled up in just a few hours at high acquisition rates. On the contrary, with the online solution, only a small portion of the acquired signals (or only alarm information about potentially dangerous events) can be transmitted in real time to the surface by using conventional mud-pulse telemetry. We present a lossy data compression algorithm based on a new representation of downhole data in angle domain, which is suitable for downhole implementation and may be successfully applied to both online and offline solutions. Numerical tests based on real field data achieve compression ratios up to 112:1 without major loss of information. This allows a significant increase in downhole time acquisition and in real-time information that can be transmitted through mud-pulse telemetry.     

Partial-norm-constrained sparse recovery algorithm and its application on single carrier underwater-acoustic-data telemetry

To solve the problem of single carrier underwater-acoustic-data telemetry,compressive sensing (CS) provides competitive performance of compression and recovery with low energy consumption.The primary objective of CS is to minimize the l₀norm,which is an NP hard problem.Hence,the common methods were transferred to minimize l₁norm.However,l₁norm minimization provided a limited accuracy.A partial-norm-constraint (PNC) based sparse signal recovery method was derived,which adopted PNC as a zero attraction in a Lagrange method,to distribute the soft threshold for the non-zero taps.The proposed method is used for at-sea data telemetry.Combining with DCT,the proposed method improves the recovery accuracy.     

RS码在空空导弹遥测系统中的应用

为了增强空空导弹遥测系统抗误码能力,使遥测数据传输更为可靠,需要在遥测系统弹栽部分采用纠错编码技术。根据空空导弹遥测系统的特点采用RS码作为遥测系统纠错编码,分析了RS码的编码原理及实现方法,探讨了数据交织与解交织的原理,介绍了遥测系统中RS码的应用方法。实验证明,在设计能力范围内,Rs码可正确恢复遥测数据传输过程中产生的误码,完全满足设计需求。     

基于POWERPC＋FPGA架构的飞行试验振动数据实时分析系统设计

飞行试验振动信号具有采样率高、数据量大、处理复杂的特点,在现有条件下,通过遥测链路很难将大量的振动数据实时传输至地面监控系统。针对试飞测试的需要,结合某型号的试飞关键技术攻关研究,突破试飞振动数据实时处理系统的一些关键技术,对被试飞机的振动信号进行实时分析,将分析结果实时发送至地面监控系统,以减小遥测传输带宽,真正实现高采样信号振动数据的遥测实时监控。     

Implantable Myoelectric Sensors (IMESs) for Intramuscular Electromyogram Recording

We have developed a multichannel electrogmyography sensor system capable of receiving and processing signals from up to 32 implanted myoelectric sensors (IMES). The appeal of implanted sensors for myoelectric control is that electromyography (EMG) signals can be measured at their source providing relatively cross-talk-free signals that can be treated as independent control sites. An external telemetry controller receives telemetry sent over a transcutaneous magnetic link by the implanted electrodes. The same link provides power and commands to the implanted electrodes. Wireless telemetry of EMG signals from sensors implanted in the residual musculature eliminates the problems associated with percutaneous wires, such as infection, breakage, and marsupialization. Each implantable sensor consists of a custom-designed application-specified integrated circuit that is packaged into a biocompatible RF BION capsule from the Alfred E. Mann Foundation. Implants are designed for permanent long-term implantation with no servicing requirements. We have a fully operational system. The system has been tested in animals. Implants have been chronically implanted in the legs of three cats and are still completely operational four months after implantation.      

The Galileo mission to Jupiter and Doppler wind measurements

The results of previous atmospheric entry missions are reviewed, including the Pioneer Venus, Venera, and Vega missions. The Galileo mission is then described. The dual-vehicle (probe and orbiter) spacecraft was launched in October 1989 and will reach Jupiter in December 1995. The spacecraft and its hardware are described. The method used to measure the variation of wind velocities with altitude in the upper Jovian atmosphere, a key objective of the mission, is examined. The radio propagation environment of that atmosphere and its effects on the probe signal are discussed. Other errors that can affect the frequency of the received telemetry and thereby reduce the accuracy of the recovered wind profile are considered     

Polarization-, Wavelength-, and Filter-Free All-Optical Clock Recovery in a Passively Mode-Locked Laser Diode With Orthogonally Pumped Polarization-Diversity Configuration

We proposed and demonstrated all-optical clock recovery system using a monolithic mode-locked laser diode (MLLD) that operated with less sensitivity to the polarization and the wavelength of the input data signals also with no bandpass filter to eliminate the input signal-components. The keys to this new technique are the MLLD integrated with a tensile-strained quantum-well saturable absorber and a new polarization-diversity setup by signal input orthogonally polarized to the lasing polarization of the MLLD. This approach was experimentally validated in the 40 Gbps clock recovery experiments. The results exhibited excellent performance of the clock recovery with low timing jitters (<0.3 ps) remaining small dependence on the wavelength and the polarization of the input data signals and input-signal suppression less than -30 dB with no use of the bandpass filter. We also succeeded in the stable clock recovery for the input of polarization-scrambled data signals.     

A Low-Power Integrated Circuit for a Wireless 100-Electrode Neural Recording System

Recent work in field of neuroprosthetics has demonstrated that by observing the simultaneous activity of many neurons in specific regions of the brain, it is possible to produce control signals that allow animals or humans to drive cursors or prosthetic limbs directly through thoughts. As neuroprosthetic devices transition from experimental to clinical use, there is a need for fully-implantable amplification and telemetry electronics in close proximity to the recording sites. To address these needs, we developed a prototype integrated circuit for wireless neural recording from a 100-channel microelectrode array. The design of both the system-level architecture and the individual circuits were driven by severe power constraints for small implantable devices; chronically heating tissue by only a few degrees Celsius leads to cell death. Due to the high data rate produced by 100 neural signals, the system must perform data reduction as well. We use a combination of a low-power ADC and an array of "spike detectors" to reduce the transmitted data rate while preserving critical information. The complete system receives power and commands (at 6.5 kb/s) wirelessly over a 2.64-MHz inductive link and transmits neural data back at a data rate of 330 kb/s using a fully-integrated 433-MHz FSK transmitter. The 4.7times5.9 mm² chip was fabricated in a 0.5-mum 3M2P CMOS process and consumes 13.5 mW of power. While cross-chip interference limits performance in single-chip operation, a two-chip system was used to record neural signals from a Utah Electrode Array in cat cortex and transmit the digitized signals wirelessly to a receiver     

舰载式高精度水下定位系统

阐述了水下二次定位系统的原理和特点,研究了水下应答器定位系统中所涉及的高精度测距技术。详细介绍了水下应答器收发信号形式,提出了利用线性调频信号和码分多址扩频通信的数据包提高定位精度的理论,结合DSP处理平台,全面论述了系统设计思想,解决了低信噪比条件下多目标信号检测的关键问题。