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
Digital broadcasting systems for television, sound and data services Framing structure, channel coding and modulation for 11/12 GHz satellite services
标签： broadcasting television structure services
上传时间： 2016-01-03
上传用户：rishian
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 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
In this letter, the error performance of an ultra-wideband (UWB) system with a hybrid pulse amplitude and position modulation (PAPM) scheme over indoor lognormal fading channels is analyzed. In the PAPM UWB system, input data is modulated onto both the pulse amplitudes and pulse positions.
标签： ultra-wideband performance amplitud letter
上传时间： 2014-01-08
上传用户：yulg
用fpga实现的DA转换器，有说明和源码，VDHL文件。 A PLD Based Delta-Sigma DAC Delta-Sigma modulation is the simple, yet powerful, technique responsible for the extraordinary performance and low cost of today s audio CD players. The simplest Delta-Sigma DAC consists of a Delta-Sigma modulator and a one bit DAC. Since, both of these components can be realized using digital circuits, it is possible to implement a low precision Delta-Sigma DAC using a PLD.
上传时间： 2016-06-10
上传用户：bjgaofei
The PWM_1 project is a simple program for the STM32F103RBT6 using Keil MCBSTM32 Evaluation Board and demonstrating the use of PWM (Pulse Width modulation) with Timer TIM4.
标签： Evaluation project program MCBSTM
上传时间： 2013-12-25
上传用户：familiarsmile
This project allows you to learn communication systems in greater depth. It contains the Simulink files (*.mdl) which are block design files of various communication systems such as AM, DSB-SC, FM, PLL, Data Acquisition, Digital Data Transmission, PCM and Delta modulation. The idea here is to implement experiments of a traditional communication lab using Simulink. Most of the block diagrams are self explanatory. More information on the systems and their implementation can be found in the word documents included in the lab directories
标签： communication Simulink contains project
上传时间： 2013-12-09
上传用户：lz4v4
This a GUI based system. The GUI is invoked from the command line by typing "ui_start". The GUI is self explanatory. Tool tips are given in blue color. The cursor needs to be positioned on these for detailed explanation. The main file is "runsim.m". In these simulations the SISO option is not explicitly given. This is because the SISO result for a particular type of modulation is shown in every plot for purposes of comparison. This software has been tested on MATLAB version 6.0 and above with signal processing and communication toolbox options.
上传时间： 2016-08-24
上传用户：杜莹12345
s3c2410提供了5个16位的Timer（Timer0~Timer4），其中Timer0~Timer3支持Pulse Width modulation—— PWM（脉宽调制 ）。Timer4是一个内部定时器（internal timer），
上传时间： 2013-12-16
上传用户：569342831
