Jitter is extremely important in systems using PLL-based clock drivers. The effects of jitter range from not having any effect on system operation to rendering the system completely non-functional. This application note provides the reader with a clear understanding of jitter in high-speed systems. It introduces the reader to various kinds of jitter in high-speed systems, their causes and their effects, and methods of reducing jitter. This application note will concentrate on jitter in PLL-based frequency synthesizers.
標(biāo)簽: extremely PLL-based important drivers
上傳時間: 2014-11-25
上傳用戶:asddsd
A self-designed control of PC parallel port communication is introduced in this paper.Taking advantage of the MFC ActiveX technology, it is developed in Visual C++ and offset the scarcity of the control of PC parellel paort communication. An example of frequency measurement shows the detail procedure and application of the control.
標(biāo)簽: self-designed communication introduced parallel
上傳時間: 2015-12-02
上傳用戶:Miyuki
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.
標(biāo)簽: performance asymptotic examines non-data
上傳時間: 2015-12-30
上傳用戶:225588
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.
標(biāo)簽: scientific parameter interest decoding
上傳時間: 2015-12-30
上傳用戶:894898248
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.
標(biāo)簽: synchronization Carrier-phase multiplicativ approached
上傳時間: 2013-11-28
上傳用戶:windwolf2000
這是一個模擬第3類模式地震波的matlab腳本。 This a collection of Matlab scripts that solve the antiplane (mode III) earthquake dynamic problem with slip-weakening friction, on a 1D fault embedded in a 2D homogeneous elastic unbounded medium. The problem is formulated as a boundary integral equation and the elastodynamic kernels are analytically derived in the spectral domain (spatial wavenumber). The method is explained e.g. by Morrysey and Geubelle (1997), and has been improved and extensively used by Nadia Lapusta, Alain Cochard, etc.
標(biāo)簽: collection antiplane scripts matlab
上傳時間: 2013-12-26
上傳用戶:遠(yuǎn)遠(yuǎn)ssad
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.
標(biāo)簽: bit-error-rate performance simulates the
上傳時間: 2014-01-13
上傳用戶:whenfly
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
標(biāo)簽: communication computers software wireless
上傳時間: 2014-05-29
上傳用戶:wangdean1101
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)
標(biāo)簽: Broadcast Digital 8226 Applications
上傳時間: 2016-03-23
上傳用戶:cc1
Programs in the irregular grid design package described in this manual are used to carry out five main functions: verification and adjustment of coastline and bathymetric data preparation of an irregular triangular depth grid covering the domain to be modelled production of a preliminary irregular triangular model grid with nodes suitably positioned for accurate and efficient numerical modelling interactive checking and editing, including trimming and joining, of model grid display and plotting of model output.
標(biāo)簽: described irregular Programs package
上傳時間: 2016-04-09
上傳用戶:fnhhs
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