We address the problem of blind carrier frequency-offset (CFO) estimation in quadrature amplitude modulation, phase-shift keying, and pulse amplitude modulation communications systems.We study the performance of a standard CFO estimate, which consists of first raising the received signal to the Mth power, where M is an integer depending on the type and size of the symbol constellation, and then applying the nonlinear least squares (NLLS) estimation approach. At low signal-to noise ratio (SNR), the NLLS method fails to provide an accurate CFO estimate because of the presence of outliers. In this letter, we derive an approximate closed-form expression for the outlier probability. This enables us to predict the mean-square error (MSE) on CFO estimation for all SNR values. For a given SNR, the new results also give insight into the minimum number of samples required in the CFO estimation procedure, in order to ensure that the MSE on estimation is not significantly affected by the outliers.
标签： frequency-offset estimation quadrature amplitude
上传时间： 2014-01-22
上传用户：牛布牛
Carrier-phase synchronization can be approached in a general manner by estimating the multiplicative distortion (MD) to which a baseband received signal in an RF or coherent optical transmission system is subjected. This paper presents a unified modeling and estimation of the MD in finite-alphabet digital communication systems. A simple form of MD is the camer phase exp GO) which has to be estimated and compensated for in a coherent receiver. A more general case with fading must, however, allow for amplitude as well as phase variations of the MD. We assume a state-variable model for the MD and generally obtain a nonlinear estimation problem with additional randomly-varying system parameters such as received signal power, frequency offset, and Doppler spread. An extended Kalman filter is then applied as a near-optimal solution to the adaptive MD and channel parameter estimation problem. Examples are given to show the use and some advantages of this scheme.
标签： synchronization Carrier-phase multiplicativ approached
上传时间： 2013-11-28
上传用户：windwolf2000
电子书籍，软件构架与设计systems Analysis and Design Comprehensive Introduction - Cour...pdf
上传时间： 2016-01-12
上传用户：努力努力再努力
CCISP考试指南与导读 CISSP STUDY NOTES FROM CISSP PREP GUIDE 1 DOMAIN 1 – SECURITY MANAGEMENT PRACTICES 2 DOMAIN 2 – ACCESS CONTROL systems 7 DOMAIN 3 – TELECOM AND NETWORK SECURITY 13 DOMAIN 4 – CRYPTOGRAPHY 34 DOMAIN 5 – SECURITY ARCHITECTURE AND MODELS 46 DOMAIN 6 – OPERATIONS SECURITY 56 DOMAIN 7 – APPLICATIONS AND SYSTEM DEVELOPMENT 63 DOMAIN 8 – BUSINESS CONTINUITY AND DISASTER RECOVERY PLANNING 70 DOMAIN 9 – LAW, INVESTIGATION AND ETHICS 78 DOMAIN 10 – PHYSICAL SECURITY 87
标签： CISSP MANAGEMENT PRACTICES SECURITY
上传时间： 2014-02-13
上传用户：sy_jiadeyi
With this foundation, you explore a development model that addresses the complete range of issues in the design of embedded communications software, including real-time operating systems, hardware and software partitioning, layering, and protocol stacks.
标签： development foundation addresses complete
上传时间： 2016-01-16
上传用户：zyt
ST7529液晶驱动 The ST7529 is a driver & controller LSI for 32 gray scale graphic dot-matrix liquid crystal display systems. It generates 255 Segment and 160 Common driver circuits. This chip is connected directly to a microprocessor, accepts Serial Peripheral Interface (SPI), 8-bit/16-bit parallel or IIC display data and stores in an on-chip display data RAM. It performs display data RAM read/write operation with no external operating clock to minimize power consumption. In addition, because it contains power supply circuits necessary to drive liquid crystal, it is possible to make a display system with the fewest components.
标签： 7529 controller dot-matrix graphic
上传时间： 2013-12-02
上传用户：奇奇奔奔
The PCI Utilities package contains a library for portable access to PCI bus configuration registers and several utilities based on this library. In runs on the following systems: Linux (via /sys/bus/pci, /proc/bus/pci or i386 ports) FreeBSD (via /dev/pci) NetBSD (via libpci) OpenBSD (via /dev/pci) GNU/kFreeBSD (via /dev/pci) Solaris/i386 (direct port access) Aix (via /dev/pci and odmget) GNU Hurd (direct port access) Windows (direct port access)
标签： configuration PCI Utilities registers
上传时间： 2016-01-20
上传用户：徐孺
FIST可堆叠文件系统，linux文件系统修改相关的开源软件，使得对linux文件系统功能的改进很简单了 The FiST (File System Translator) system combines two methods to solve the above problems in a novel way: a set of stackable file system templates for each operating system, and a high-level language that can describe stackable file systems in a cross-platform portable fashion. Using FiST, stackable file systems need only be described once. FiST s code generation tool, fistgen, compiles a single file system description into loadable kernel modules for several operating systems (currently Solaris, Linux, and FreeBSD). The project demonstrates that with FiST, code size and development time are reduced significantly, while imposing a small performance overhead of only 1-2％. These benefits are achieved, as well as portability, without changing existing operating systems or file system.
上传时间： 2014-01-10
上传用户：xsnjzljj
CheckMate is a MATLAB-based tool for modeling, simulating and investigating properties of hybrid dynamic systems. Hybrid systems are modeled using the Simulink graphical user interface (GUI). Parameters and specifications are entered using both the Simulink GUI and user-defined m-files. CheckMate commands are entered in the MATLAB command window.
标签： investigating MATLAB-based simulating properties
上传时间： 2013-12-13
上传用户：源弋弋
Introduction A shared library is a collection of functions that are available for use by one or more applications running on a system. On Windows operating systems, the library is compiled into a dynamic link library (.dll) file. At run-time, the library is loaded into memory and made accessible to all applications.
标签： Introduction collection available functions
上传时间： 2014-01-26
上传用户：2467478207
