TPC编译码的硬件实现

首先介绍了TPC编译码的原理,并介绍了AHA公司生产的第一代TPC编译码芯片AHA4501,该芯片通过对内部寄存器的控制能够完成不同TPC码的编译码。在理论研究的基础上阐述了TPC硬件实现系统的设计方案。系统的外部电路基本上都由FPGA完成,重点介绍AHA4501芯片的初始化流程,使之能够正确完成TPC的编译码。     

Turbo乘积码在衰落信道中的应用

基于Turbo乘积码的编译码原理,利用Matlab仿真工具,对以(64,57,4)扩展汉明码为子码的Turbo乘积码进行迭代次数、量化比特数等不同参数的性能仿真,根据仿真结果选取最佳的设计参数,同时通过仿真给出了Turbo乘积码在衰落信道中的应用效果。结合Matlab仿真,在Quartus环境中完成编译码算法的硬件设计与调试,并将其应用到无线通信调制解调器中。测试结果表明,Turbo乘积码显著改善了调制解调器在衰落信道中的误码性能。     

删余Turbo乘积码的编译码算法分析

基于现有的Turbo乘积码的编译码方法,提出一种附加删余的Turbo乘积码编译码算法,介绍其编码器的构造方法,阐述了译码算法及实现框图,分析了删余信息对传输帧长的影响,仿真了其误码性能,并与未删余的Turbo乘积码做比较。分析和仿真结果表明,附加删余的Turbo乘积码可满足特定系统传输速率及帧长的需要,在相同的信噪比下,删余Turbo乘积码的误码性能优于未加删余的误码性能。     

Turbo乘积码编码器的FPGA设计与实现

Turbo乘积码(Turbo Product Codes)是一种先进的前向纠错(FEC,Forward Error Correction)信道编码,纠错性能好,编码效率高,同时由于其编码构造采用了线性分组码,所以译码方法简单,实现复杂度低。本文对Turbo乘积码编码技术进行了研究,给出了编码器的FPGA设计实现方案,该编码器的设计在Xilinx公司Virtex-II系列的FPGA平台上进行了实验验证。实验结果表明,本设计的编码器满足预期指标要求。     

一种SC-FDE散射通信系统的MIMO技术方案

在使用2付发射天线、2付接收天线和2个发射频率的传统散射通信系统基础上,提出了一种应用于单载波频域均衡(SC-FDE)散射通信系统的多输入多输出(MIMO)技术方案,可以在保证4重分集的情况下提供2倍的数据传输速率。提出的MIMO技术方案只需在发射端增加2部发射机,不需改变接收机的射频支路结构,具有实现简单的优点。仿真表明,提出的MIMO技术方案在无信道编译码时的误比特率(BER)性能比相应的传统分集系统性能恶化约1.9dB,在进行(64,57)(64,57)Turbo乘积码编译码时的性能恶化只有1.6dB,因此,与使用单独的2套传统分集系统提供2倍的数据传输速率相比,分别具有1.1dB和1.4dB的功率增益,而且具有体积小、成本低的优点。     

Turbo乘积码在无人机测控技术中的应用分析

Turbo乘积码是一种易于硬件实现的分组码,具有延时短和纠错性能好等优越性。通过对Turbo乘积码Chase软输出改进算法的分析和仿真,得出了不同码率和测试序列个数等参数对Turbo乘积码译码性能的影响。结合无人机常用的BPSK测控信号进行了仿真实验,对仿真结果进行了性能分析,验证了Turbo乘积码在无人机测控系统中应用的可行性,并给出了Turbo乘积码在无人机测控领域应用的建议参数。     

Turbo乘积码对星间光通信链路的性能改善分析

通过联合界技术较为详细地给出了Turbo乘积码的最大似然译码限,并比较了在星间光通信链路中Turbo乘积码和Turbo卷积码及传统级联码的纠错性能.研究表明,Turbo乘积码的纠错性能优于传统级联码以及Turbo卷积码.     

Turbo码编译码技术

深入地介绍了Turbo码编译码技术,包括:Turbo码编码器的结构、Turbo码的译码器结构、Turbo码的迭代译码算法和Turbo码的性能及其优、缺点。Turbo码编译码技术以其优异的性能和可实现的复杂度特性定有良好的应用前景。     

RS码专用芯片接口的FPGA实现

现代数字通信中RS纠错编码已得到广泛应用,专门针对RS编译码的专用芯片也因此被广泛应用.文中介绍了RS码专用芯片AHA4012B的使用方法,并且给出了用FPGA(现场可编程门阵列)实现与AHA4012B接口的方法.该接口已经在实际调制解调器电路中运用,工作稳定可靠.     

LTE链路中Turbo编译码原理及FPGA实现

介绍了Turbo码的编译码原理和常用的译码算法。使用Altera DE4开发板对Turbo编译码进行硬件实现,给出了实现中功能模块的详细划分情况。本次实现的Turbo码的相关参数取自3GPP的长期演进(LTE)协议,针对LTE中不同场景下码长不同的情况,对硬件采取了可配置参数的设计,符合LTE链路中任意情况下的Turbo码的规范。最后搭建了验证平台,将硬件得到的数据和仿真的结果进行对比,验证了实现的正确性。     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers

A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.     

Diode-end-pumped Nd:YVO4/LBO lasers with 4.2W continuous-wave output at 457 nm

A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.     

A rigorous proof of MIMO channel capacity’s increase with antenna number

It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output（MIMO） communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.     

Call for Papers

正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks