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FREQUENCY-divis

  • This paper examines the asymptotic (large sample) performance of a family of non-data aided feedfor

    This paper examines the asymptotic (large sample) performance of a family of non-data aided feedforward (NDA FF) nonlinear least-squares (NLS) type carrier frequency estimators for burst-mode phase shift keying (PSK) modulations transmitted through AWGN and flat Ricean-fading channels. The asymptotic performance of these estimators is established in closed-form expression and compared with the modified Cram`er-Rao bound (MCRB). A best linear unbiased estimator (BLUE), which exhibits the lowest asymptotic variance within the family of NDA FF NLS-type estimators, is also proposed.

    标签: performance asymptotic examines non-data

    上传时间: 2015-12-30

    上传用户:225588

  • In recent years large scientific interest has been devoted to joint data decoding and parameter est

    In recent years large scientific interest has been devoted to joint data decoding and parameter estimation techniques. In this paper, iterative turbo decoding joint to channel frequency and phase estimation is proposed. The phase and frequency estimator is embedded into the structure of the turbo decoder itself, taking into consideration both turbo interleaving and puncturing. Results show that the proposed technique outperforms conventional approaches both in terms of detection capabilities and implementation complexity.

    标签: scientific parameter interest decoding

    上传时间: 2015-12-30

    上传用户:894898248

  • Carrier-phase synchronization can be approached in a general manner by estimating the multiplicativ

    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

  • This program simulates the bit-error-rate (BER) performance of OSTBC with L=4 antennas over the fr

    This program simulates the bit-error-rate (BER) performance of OSTBC with L=4 antennas over the frequency flat Rayleigh block fading channel The code is developed for real orthogonal design, code rate 1/2 modulation- 16 QAM with gray coding resulting in 2 bits/sec/Hz.

    标签: bit-error-rate performance simulates the

    上传时间: 2014-01-13

    上传用户:whenfly

  • This project aim was to build wireless software modem for data communication between two computers

    This project aim was to build wireless software modem for data communication between two computers using an acoustic interface in the voice frequency range (20Hz– 20,000Hz). The transmitting antenna is a speaker (frequency response of: 90Hz – 20,000Hz) and the receiving antenna is a microphone (frequency response of: 100Hz – 16,000Hz). The test files used as information files were text files. This goal was attained both in an incoherent scheme and in a coherent scheme. Build under Matlab code, our modem uses OFDM (orthogonal frequency division multiplexing) modulation, synchronization by LMS sequence, channel estimation (no equalizer) via pilot tones. The symbols are either PSK or ASK for a constellation size of 2 or 4. To optimize the probability of error, these symbols were mapped using Gray mapping. Report

    标签: communication computers software wireless

    上传时间: 2014-05-29

    上传用户:wangdean1101

  • OFDM Modem Applications • Digital Video Broadcast (DVB) • Digital Audio Broadcast (DAB)

    OFDM Modem Applications • Digital Video Broadcast (DVB) • Digital Audio Broadcast (DAB) • Broadband Wireless Access (802.16x) • Wireless LAN (802.11x & HiperLAN) Orthogonal OFDM Sub-carriers Orthogonal Frequency Division Multiplexing (OFDM)

    标签: Broadcast Digital 8226 Applications

    上传时间: 2016-03-23

    上传用户:cc1

  • A digital fi‘equeney meter designed with FPGA development software Q-~us 11 is introduced.The 1 Hz—l

    A digital fi‘equeney meter designed with FPGA development software Q-~us 11 is introduced.The 1 Hz—l MHz input measured pulse signals of the digital ii‘equency meter can be used for measuring frequency,period,pulse width and duty ratio,etc.The test results stably display O71 3 seven—segment numeric tubes,and the measuring ranges may be switched over automatically.The measuring error is equal to or less than 0.1%.

    标签: development introduced designed software

    上传时间: 2016-04-09

    上传用户:stewart·

  • DFT(Discrete Fourier Transformation)是数字信号分析与处理如图形、语音及图像等领域的重要变换工具

    DFT(Discrete Fourier Transformation)是数字信号分析与处理如图形、语音及图像等领域的重要变换工具,直接计算DFT的计算量与变换区间长度N的平方成正比。当N较大时,因计算量太大,直接用DFT算法进行谱分析和信号的实时处理是不切实际的。快速傅立叶变换(Fast Fourier Transformation,简称FFT)使DFT运算效率提高1~2个数量级。其原因是当N较大时,对DFT进行了基4和基2分解运算。FFT算法除了必需的数据存储器ram和旋转因子rom外,仍需较复杂的运算和控制电路单元,即使现在,实现长点数的FFT仍然是很困难。本文提出的FFT实现算法是基于FPGA之上的,算法完成对一个序列的FFT计算,完全由脉冲触发,外部只输入一脉冲头和输入数据,便可以得到该脉冲头作为起始标志的N点FFT输出结果。由于使用了双ram,该算法是流型(Pipelined)的,可以连续计算N点复数输入FFT,即输入可以是分段N点连续复数数据流。采用DIF(Decimation In Frequency)-FFT和DIT(Decimation In Time)-FFT对于算法本身来说是无关紧要的,因为两种情况下只是存储器的读写地址有所变动而已,不影响算法的结构和流程,也不会对算法复杂度有何影响。

    标签: Transformation Discrete Fourier DFT

    上传时间: 2016-04-12

    上传用户:lx9076

  • This example demonstrates how the C8051F06x SMBus interface can communicate // with a 256 byte I2C

    This example demonstrates how the C8051F06x SMBus interface can communicate // with a 256 byte I2C Serial EEPROM (Microchip 24LC02B). // - Interrupt-driven SMBus implementation // - Only master states defined (no slave or arbitration) // - Timer4 used by SMBus for SCL low timeout detection // - SCL frequency defined by <SMB_FREQUENCY> constant

    标签: demonstrates communicate C8051F06x interface

    上传时间: 2016-04-12

    上传用户:hanli8870

  • 在DAB系统中的频率同步

    在DAB系统中的频率同步,载频同步,参考一下Carrier frequency offset estimation of DAB receiver based on phase reference symbol

    标签: DAB 频率同步

    上传时间: 2014-11-23

    上传用户:songrui