Description: 对ofdm插入梳妆（comb)导频，比较了有ls信道估计和无信道估计，并仿真得到了不同信噪比下，误码率曲线；信道为多径瑞利衰落加上白噪声；经过调试，已经能正确运行-Insert the dressing on the OFDM (comb) Pilot compared ls has no channel estimation and channel estimation, and simulation have been under different signal to noise ratio, bit error rate curve channel for multipath Rayleigh fading plus white noise after debugging have been able to run correctly Platform: |
Size: 3072 |
Author:吕明相 |
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Description: 基于Combs Pilot的OFDM信道估计，计算不同信噪比下的误码性能曲线，并画图-Combs Pilot-based channel estimation of OFDM, signal to noise ratio under different bit error performance curve, and drawing Platform: |
Size: 3072 |
Author:韩聪 |
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Description: WLAN仿真－发送机
wlan No Comments
设置完系统参数后，开始产生发送数据。
1. 产生随机的发送bit（tx_bits），这里不考虑信道编码。
2. QAM映射
3. 将数据映射到不同载波，形成OFDM符号
4. 产生pilot，并将pilot插入OFDM符号中
5. 加入dc和guard子载波
6. 进行ifft，将频域信号变到时域，并加入循环前缀
7. 对信号进行overlap window
8. 在时域产生short preamble
9. 在时域产生long preamble
10. 将preamble和数据符号组成packet
11. 升采样
得到信道传输的数据Tx_signal_up
具体程序见附件 wlan_transmitter.m-WLAN Simulation- wlan No Comments transmitter system parameters set finished, the beginning to have to send data. 1. Have sent random bit (tx_bits), here does not consider channel coding. 2. QAM mapping 3. The data is mapped to a different carrier to form OFDM symbols 4. Have a pilot, and pilot inserted OFDM symbols 5. Adding dc and guard subcarriers 6. To carry out ifft, will change the frequency domain signal to time domain, and add cyclic prefix 7. the signals overlap window8. In the time domain have a short preamble9. In the time domain have a long preamble10. the preamble and data symbols packet11. or sampling received data transmission channel Tx_signal_up specific procedures see Annex wlan_transmitter.m Platform: |
Size: 1024 |
Author:福东方 |
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Description: 信道估计程序，采用块状导频的办法，OFDM信号，采用自适应算法对瑞利信道模拟，有效地估计了信道-Channel estimation procedure for the pilot block approach, OFDM signal, using adaptive algorithm for Rayleigh channel simulation, an effective tool in estimating the channel Platform: |
Size: 12096512 |
Author: |
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Description: 本文在分析移动无线信道衰落特性的基础上,阐述了OFDM系统的基本原理,主要研究了OFDM通信系统中的基于导频符号的信道估计问题,分析了几种经典的信道估计算法以及相关的关键技术环节。 在此基础上介绍了OFDM技术在现实中的一个应用——WLAN IEEE802.11a系统模型,利用Matlab仿真软件完成OFDM系统信号生成、噪声生成、导频插入、循环前缀、调制、解调等部分的设计,最后结合计算机仿真对系统关键技术(导频、循环前缀、估计算法)的有效性和可行性进行了全面的分析与比较。适合matlab研究-Based on the analysis of mobile channel fading characteristics based on the OFDM system on the basic principles of research in the OFDM communication system of the pilot symbols based on channel estimation problem, an analysis of several classical channel estimation algorithm and the associated key technical links. On this basis, introduced OFDM technology in a practical application- WLAN IEEE802.11a system model, using Matlab simulation software to complete OFDM signal generation, noise generation, pilot insertion, cyclic prefix, modulation, demodulation and other parts of the design, the final combination of computer simulation of the system of key technologies (pilots, cyclic prefix, it is estimated that algorithm) the effectiveness and feasibility of a comprehensive analysis and comparison. Suitable for research matlab Platform: |
Size: 1339392 |
Author:赵洪森 |
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Description: 本人的主要任务是利用MATLAB作为仿真工具来实现OFDM在无线信道上的系统仿真，其中主要的仿真模块包括信源产生，波形预处理，调制，插入导频信号和保护间隔，无线信道，接收滤波器，信道估计和信号补偿，解调，计算误比特率模块。-My main task is to use MATLAB as a simulation tool to achieve the wireless channel on the OFDM system simulation, in which the main simulation modules, including source generation, waveform pre-processing, modulation, inserting pilot signals and guard interval, radio channel, receive filtering device, channel estimation and signal compensation, demodulation, bit error rate calculation module. Platform: |
Size: 32768 |
Author:雷月 |
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Description: 基于16QAM调制解调的OFDM信道估计，计算了不同信噪比下的误码性能曲线，并画出了图。-Comb based on the OFDM pilot channel estimation, calculation of the BER performance under different signal to noise ratio curve, and draw the map. Platform: |
Size: 1024 |
Author:tang |
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Description: Add pilot symbols to the input data just before transmission
2. Implement cyclic prefix (CP), use 10 of symbol length. Divide the 64
input data points into 8-bit streams, generate and append the CP based
on each symbol
3. Include complex noise into transmitted signal
Organization of Transmitter end of OFDM System
a. Generate Data
b. Modulate
c. Serial to Parallel
d. Cyclic Prefix (CP)
e. Add Pilot points
f. IFFT
g. Parallel to Serial
-Add pilot symbols to the input data just before transmission
2. Implement cyclic prefix (CP), use 10 of symbol length. Divide the 64
input data points into 8-bit streams, generate and append the CP based
on each symbol
3. Include complex noise into transmitted signal
Organization of Transmitter end of OFDM System
a. Generate Data
b. Modulate
c. Serial to Parallel
d. Cyclic Prefix (CP)
e. Add Pilot points
f. IFFT
g. Parallel to Serial
Platform: |
Size: 10240 |
Author:ibrahim |
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Description: OFDM信号的导频的插入包含LS,LMMSE,线性插值等-OFDM pilot signal insertion include LS, LMMSE, linear interpolation Platform: |
Size: 28672 |
Author:程程序 |
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Description: 基于期望最大化(EM)的最大后验信道估计算法(MAP)在高信噪比(SNR)下将很难获得较低的估计误差,并且,对于导频辅助的MIMO-OFDM系统,OFDM符号的数据传输效率随着发送天线的增加而明显下降.为改善这两种缺陷,引入一种等效的信号模型来改善高SNR下的估计性能 在相邻多个OFDM符号内使用相移正交导频序列和联合估计来提高系统的数据传输效率和估计性能 根据角域内信道间的独立性来减小噪声对估计的影响.通过仿真实验可知,所提算法具有更小的估计误差和更高的数据传输效率.-Maximum a posteriori(MAP) channel estimation algorithm usually uses expectation maximum(EM) algorithm to decrease the high computation.However,this kind of operation has a difficulty in obtaining ideal estimation performance at high signal to noise ratio(SNR) because of the convergent feature of EM algorithm.In addition,for pilot-based multiple-input multiple-output with orthogonal frequency division multiplexing(MIMO-OFDM) systems,data transmission efficiency of OFDM symbol will be reduced with the increas... Platform: |
Size: 134144 |
Author:王睿 |
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Description: ofdm 系统的仿真 利用导频信号来估计信道
-ofdm system simulation and use the pilot signal to estiamte the channel information Platform: |
Size: 28672 |
Author:wangxin |
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Description: OFDM信道估计程序 是基于导频的OFDM信号信道估计的matlab程序-OFDM channel estimation procedures is estimated based pilot OFDM signal channel matlab program Platform: |
Size: 8192 |
Author:wangyuxian |
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Description: OFDM系统中的基于导频信号的信道估计，非常适合与初学者使用！-OFDM system based on pilot signal channel estimation, very suitable for beginners! Platform: |
Size: 7168 |
Author:qqnmd |
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Description: 首先根据短训练字的特性进行相关运算，进行信号到达检测，当检测到相关值大于门限一定次数后，认为有信号到达。然后根据长训练字的特性，进行相关运算，进行OFDM符号FFT窗口起始位置的估计。估计出FFT窗口的位置后，先在时域进行小频偏的估计，将两个长训练字进行小频偏补偿后，进行FFT运算，根据FFT运算的结果进行整数倍频偏的估计。这些参数估计完成后，就可以进行数据解调了。先对数据部分进行完整的频偏补偿，然后根据估计的FFT窗口位置进行FFT运算得到频域的数据，进行解调。然后在对应于导频的子载波位置上提取出导频信息，根据导频信息估计出剩余定时误差以及剩余的信道响应误差，将误差量送入环路进行跟踪。当收到所有数据后，重新回到信号到达检测状态，进行下一次信号到达的检测和信号接收。-First of all, according to the characteristics of the short training word correlation calculation of the signal reaching the detector, when the detected correlation value is greater than the threshold of a certain frequency and that a signal arrives. Then, the correlation calculation according to the characteristics of the long training word, the initial estimate of the location of the OFDM symbol FFT window. The estimated position of the FFT window, the first small frequency offset estimation in the time domain, the small frequency offset compensation, the two long training word FFT operation integer frequency offset estimate, according to the result of the FFT operation. After the completion of these parameter estimates, data demodulation. The complete frequency offset compensation, and then based on the estimated FFT window position for the FFT operation to obtain a frequency domain data, demodulates the first data part. Then in a position corresponding to the pilot subcarriers extr Platform: |
Size: 124928 |
Author:章田 |
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Description: 一种新的符号定时和载波频率同步算法,该算法将OFDM符号分成几部分。它使用相关性和积累在几个OFDM同步算法对OFDM系统基于试点,使用前言快速、准确获取信号,在有限的时间建立同步,利用导频跟踪同步信息-A new symbol timing and carrier frequency synchronization algorithm is presented and the algorithm divides the OFDM symbol into several parts. It uses correlation and accumulation in several OFDM a synchronization algorithms for OFDM system based on pilot, using the preamble to fast and accurate acquire signal, establish synchronization in the limited time, and using pilot to track synchronization information Platform: |
Size: 1267712 |
Author:wujueying |
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Description: 首先根据短训练字的特性进行相关运算，进行信号到达检测，当检测到相关值大于门限一定次数后，认为有信号到达。然后根据长训练字的特性，进行相关运算，进行OFDM符号FFT窗口起始位置的估计。估计出FFT窗口的位置后，先在时域进行小频偏的估计，将两个长训练字进行小频偏补偿后，进行FFT运算，根据FFT运算的结果进行整数倍频偏的估计。这些参数估计完成后，就可以进行数据解调了。先对数据部分进行完整的频偏补偿，然后根据估计的FFT窗口位置进行FFT运算得到频域的数据，进行解调。然后在对应于导频的子载波位置上提取出导频信息，根据导频信息估计出剩余定时误差以及剩余的信道响应误差，将误差量送入环路进行跟踪。当收到所有数据后，重新回到信号到达检测状态，进行下一次信号到达的检测和信号接收。-First, according to the characteristics of the short training word correlation operation, the signal reaching the detector, when the detected correlation value is greater than the threshold after a certain number of times that a signal arrives. And then the characteristics of long training word, the correlation operation for the FFT window starting position of an OFDM symbol estimate. The estimated position of the FFT window, the first small frequency offset in the time domain estimation, the two long training word small frequency offset compensation, the FFT operation, the FFT result of the operation for integer frequency offset estimate. These parameter estimation is completed, the data can be demodulated on. The first portion of the data for a complete frequency offset compensation, and based on the estimated FFT window position of the FFT operation to obtain frequency domain data, demodulated. Then corresponding to the position of the pilot subcarriers are extracted on pilot inform Platform: |
Size: 11264 |
Author:wangkai |
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Description: 程序详细地介绍了OFDM系统中导频信号信道估计的作用，适用于快衰落信道，能够快速跟踪均衡信道，同时包含一个详细介绍算法（LS MMSE）的算法文档。-Procedures described in detail in the pilot signal OFDM system channel estimation role for fast fading channels, fast track channel equalization, and contains a detailed algorithm (LS MMSE) algorithm documents. Platform: |
Size: 148480 |
Author:东方泓 |
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Search - ofdm pilot signal