Description: OFDM LSE Channel Estimation；
the performance of LSE channel estimation will be evaluated based on bit error rate in received data-OFDM Channel Estimation; performance of the channel estimation will LSE be evaluated based on bit error rate in received data Platform: |
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Author:刘美 |
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Description: This code was used for making the practical measurements in section 2.3 of my thesis. This Matlab code allows an OFDM signal to be generated based on an input data file. The data can be random data, a grey scale image, a wave file, or any type of file. The generated OFDM signal is stored as a windows wave file, allowing it to be viewed, listened to and manipulated in other programs. The modified wave file can then be decoded by the receiver software to extract the original data. This code was developed for the experiments that I performed in my honours thesis, and thus has not been fully debugged.
This is the original code developed for the thesis and so has several problems with it. The BER performance given by the simulations is infact Symbol Error Rate.
-This code was used for making the practical measurements in section 2.3 of my thesis. This M atlab code allows an OFDM signal to be generated based on an input data file. The data can be rando m data, a gray scale image, a wave file, or any type of file. The OFDM signal is generated stored as a windows wave file, allowing it to be viewed. listened to and manipulated in other programs. The modified wave file can then be decoded by the receiver software to extract the original data . This code was developed for the experiments th at I performed in my honors thesis, and thus has not been fully debugged. This is the original code developed for the thesis and so ha 's several problems with it. The BER performance given by the simulations is infact Symbol Error Rate. Platform: |
Size: 161792 |
Author:王文 |
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Description: ：该文研究OFDM 系统在总功率和误比特率限定下最大化传输速率的问题，并且考虑实际系统中整数比特的限制，
提出基于灌水法则的两种比特分配算法——改进贪婪算法和对分灌水线搜索法-The maximization of data rate under the constraint of total transmit power and bit error rate is a
considerable issue in OFDM system. Recognizing that the number of bits on each subcarrier must be a discrete
number for real systems, this paper proposed two bit allocation algorithm which are modified greedy algorithm
and water filling level binary searching algorithm. Platform: |
Size: 263168 |
Author:hodog |
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Description: Beyond third generation (B3G) and fourth
generation (4G) communication systems require
bandwidth efficiency and low complexity receivers to
accommodate high data rate and large number of
users per cell. This paper provides the
recommendations for why Interleave Division Multiple
Access (IDMA) stands out among all the present day
multiple access systems. Even if IDMA is a special
case of Code Division Multiple Access (CDMA), it
simply trounces CDMA as far as the cell capacity is
concerned. In IDMA, interleavers are used as the only
means for user separation. Interleaver size can be
varied for a set of users but the recommended
interleaver size is 1024bits at which it provides better
efficiency and minimum processing delay.
Investigations carried throughout this paper are while
using 1024 bit interleavers. IDMA exhibits the
tendency to handle huge number of users. Platform: |
Size: 366592 |
Author:raghaw |
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Description: the comb pilot aided channel estimation in ofdm modulation is considered. the power of pilot subchannels is under the control.
The data experience frequency selective channel then the AWGN noise is added to make the situation worse. The bit error rate is ploted versus SNR. Platform: |
Size: 508928 |
Author:Muhammad Ali Aftab |
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Description: 码分多址(CDMA)技术作为第三代移动通信系统的核心技术，具有容量大、抗干扰能力强等优点。然而,传统的CDMA系统属于窄带扩频系统,它的数据速率比较低,不能胜任新一代移动通信系统
（beyond 3G）高速数据通信的需要。而多载波传输技术－正交频分复用（OFDM），作为后三代移动通信的核心技术，则具有高数据速率传输的特点。-Code Division Multiple Access (CDMA) technology as the third generation mobile communication system' s core technology, high capacity, anti-interference ability and so on. However, the traditional narrow-band CDMA system is spread spectrum system, and its relatively low data rate, can not do next-generation mobile communication systems (beyond 3G) high speed data communication needs. The multi-carrier transmission technology- orthogonal frequency division multiplexing (OFDM), after three generations of mobile communications as a core technology, the high data rate transmission characteristics. Platform: |
Size: 774144 |
Author:w |
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Description: As a multi-carrier modulation scheme, Orthogonal Frequency Division Multiplexing (OFDM)
technique can achieve high data rate in frequency-selective fading channels by splitting a
broadband signal into a number of narrowband signals over a number of subcarriers, where
each subcarrier is more robust to multipath. The wireless communication system with multiple
antennas at both the transmitter and receiver, known as multiple-input multiple-output
(MIMO) system, achieves high capacity by transmitting independent information over different
antennas simultaneously. The combination of OFDM with multiple antennas has been
considered as one of most promising techniques for future wireless communication systems. Platform: |
Size: 2609152 |
Author:ashish |
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Description: A multiple-input multiple-output (MIMO) communication system combined with the orthogonal frequency division multiplexing (OFDM) modulation technique can achieve reliable
high data rate transmission over broadband wireless channels. Channel state information for both single-input single-output (SISO) and MIMO systems based on pilot aided arrangement is
investigated in this paper. The estimation of channel at pilot frequencies with conventional Least Square (LS) and Minimum Mean Square (MMSE) estimation algorithms is carried out
through Matlab simulation. The performance of MIMO OFDM and SISO OFDM are evaluated on the basis of Bit Error Rate (BER) and Mean Square Error (MSE) level.-A multiple-input multiple-output (MIMO) communication system combined with the orthogonal frequency division multiplexing (OFDM) modulation technique can achieve reliable
high data rate transmission over broadband wireless channels. Channel state information for both single-input single-output (SISO) and MIMO systems based on pilot aided arrangement is
investigated in this paper. The estimation of channel at pilot frequencies with conventional Least Square (LS) and Minimum Mean Square (MMSE) estimation algorithms is carried out
through Matlab simulation. The performance of MIMO OFDM and SISO OFDM are evaluated on the basis of Bit Error Rate (BER) and Mean Square Error (MSE) level. Platform: |
Size: 729088 |
Author:loihuynh |
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Description: Reaching Higher data rate and spectral efficiency are among the challenges expected for 4G wireless systems. Combining OFDM modulation and multiple-input multipleoutput (MIMO) help for that. In this paper, performances of a WiMAX MISO-OFDM based system are studied through
measurements done in a reverberation chamber. The used antennas’ specifications are given as well as the numerical blocks description. The results obtained are compared to a reference
case with single-input single-output (SISO) in order to evaluate the studied system’s real performances Platform: |
Size: 466944 |
Author:satish |
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Description: 正交频分复用(OFDM)是第四代移动通信的核心技术,它是实现宽带无线通信和多媒 体业务发展的基础。对OFDM 技术的基本原理，关键技术以及实现进行了研究，并且通过 matlab 中的通信仿真系统simulink 对OFDM 系统进行了模拟和分析，直观和形象地得到了 OFDM 系统在时域和频域的传输性能，得出的结果表明OFDM 系统可以明显地表现出抗多 径效应引起的频率选择性衰落和提高了频谱利用率，这一特性使得它能够在高数据传输速率 的无线信道中发挥优势。-Orthogonal Frequency Division Multiplexing (OFDM) is the fourth generation mobile communication core technology, which is broadband wireless communications and multimedia development. The basic principle of OFDM technology, key technology and implementation have been studied, and by matlab simulink simulation system in the OFDM communication system was simulated and analyzed, intuitive, and get the image of the OFDM system in time domain and frequency-domain transmission performance , the results show that OFDM system can be apparent in the anti-multipath effect caused by frequency selective fading and improve the spectrum efficiency, this allows it to transmit at high data rate wireless channel advantage. Platform: |
Size: 258048 |
Author:foxlili |
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Description: 英文版，详细介绍了OFDM的基础知识，后面附有matlab仿真-Orthogonal Frequency Division Multiplexing (OFDM) is a multicarrier modulation technique that has
recently found wide adoption in a wide variety of high data rate communication systems, including Digital
Subscriber Lines (DSL), Platform: |
Size: 472064 |
Author:tianxinhui |
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Description: In high-data-rate wireless systems focus on the integration of orthogonal frequency-divisionmultiplexing (OFDM), multiple-inputmultiple-output (MIMO) and closed-loop techniques Platform: |
Size: 737280 |
Author:mustaf dhia |
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Description: Modern wireless communication systems are expected to support high data rate, allowing users to access high quality multimedia content, anytime-anywhere. To support high data rate, wideband frequency channels are required. However, frequency selective fading over wideband channels introduces inter-symbol interference (ISI) which in turn causes effective throughput to go below required level. Introduction of OFDM transforms wideband frequency selective fading problem to narrowband flat fading and solves the problem of ISI. Symbol detection under flat fading is simple and complicated equalizers at the receiver are not required. Platform: |
Size: 655360 |
Author:ravi |
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Description: 一个OFDM符号128个有效符号，插入128个虚拟子载波
符号率（即有效数据率）fsymbol，而发送速率（需要包括虚拟子载波）2fsymbol
输入的数据需要2倍的发送数据率，以便进行内插，实现位定时跟踪，即4倍fsymbol采样率的调制信号
OFDM symbol Nfft=128 points
一个OFDM符号数据点 Nfft*2 = 256 ， Guard Interval点 ＝Ng*2=64
-128 of an OFDM symbol of a valid symbol 128 inserted virtual sub-carrier
Symbol rate (the effective data rate) fsymbol sending rate (including virtual subcarriers) 2fsymbol
Of the input data needs to be 2 times the transmission data rate, in order to carry out the interpolation, to achieve the bit timing tracking, i.e. four times the sampling rate modulation signal fsymbol
OFDM symbol Nfft = 128 points
One OFDM symbol data points nfft* 2 = 256, the Guard Interval dot = Ng* 2 = 64 Platform: |
Size: 8192 |
Author:wanglei |
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Description: Multi-Carrier Modulation is a technique for data-transmission where a high-bit rate data stream is divided into several parallel low bit-rate data streams and using these low bit-rate data streams to modulate several carriers. Multi-Carrier Transmission has a lot of useful properties such as delay-spread tolerance and spectrum efficiency that encourage their use in broadband communications. OFDM is a multi-carrier modulation technique with densely spaced sub-carriers that has gained a lot of popularity among the broadband community. Platform: |
Size: 6144 |
Author:jambulingam k |
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Description: This program describes that how the binary data is transmitted by dividing data into frames.
it also analyse the Bit Error rate by 16 QAM method and viterbi decoding method. Platform: |
Size: 2048 |
Author:vimal |
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Description: Orthogonal Frequency Division Multiplexing (OFDM) is one of the latest modulation
techniques used in order to combat the frequency-selectivity of the transmission channels,
achieving high data rate without inter–symbol interference. The basic principle of OFDM is
gaining a wide spread popularity within the wireless transmission community. Furthermore,
OFDM is one of the main techniques proposed to be employed in 4 th Generation Wireless
Systems. Therefore, it is crucial to understand the concepts behind OFDM. In this paper it is
given an overview of the basic principles on which this modulation scheme is based. Platform: |
Size: 201728 |
Author:Donna Loudoe |
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Description: 在现代无线通信技术中，扩频通信是一种具有较强抗干扰性能的技术，正交频分复用(OFDM)是一种具有较高数据传输速率和频谱利用率，并能有效对抗频率选择性衰落的多载波调制技术，因而将这二者结合起来构建系统势必会进一步提高系统的抗干扰和抗衰落性能，研究其结合技术也逐渐成为无线通信领域的热点。随着3G的兴起，即将推出的LTE也将采用OFDM技术（正交频分多路复用）。
由于OFDM的多载波特性，使得直接序列扩频技术和跳频技术能够与OFDM技术进行有效的结合。在本文中,我们研究了OFDM）以及相关抗干扰抗衰落技术。同时用matlab进行了仿真，仿真结果表明，本文提出的ICI干扰消除技术在ofdm中起到了很好的效果。
-In modern wireless communication technologies, spread spectrum communication is a kind of strong anti-jamming technology, the performance of orthogonal frequency division multiplexing (OFDM) is a kind of high data rate and spectrum efficiency, and can be effective against frequency selective fading of multi-carrier modulation technology, and combine the two build system is bound to further improve the system s anti-interference and decay resistance, and study the combining technology also gradually become a hot spot in the field of wireless communications. With the development of 3 g, the upcoming LTE will also use OFDM (orthogonal frequency division multiplexing) technology.
Because OFDM multi-carrier characteristic, the direct sequence spread spectrum and frequency hopping technology can be combined with OFDM technology effectively. In this article, we studied the OFDM technology) and related anti-interference resistance to decline. Matlab simulation was carried out at the same tim Platform: |
Size: 237568 |
Author:wfyan |
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Description: 扩频通信在现代无线通信技术中是一种具有较强抗干扰性能的技术，正交频分复用(OFDM)一种具有较高数据传输速率和频谱利用率，并能有效对抗频率选择性衰落的多载波调制技术，因而将这二者结合起来构建系统势必会进一步提高系统的抗干扰和抗衰落性能，研究其结合技术也逐渐成为无线通信领域的热点。随着3G的兴起，即将推出的LTE也将采用OFDM技术（正交频分多路复用）。
由于OFDM的多载波特性，使得直接序列扩频技术和跳频技术能够与OFDM技术进行有效的结合。在本文中,我们研究了OFDM）以及相关抗干扰抗衰落技术。同时用matlab进行了仿真，仿真结果表明，本文提出的ICI干扰消除技术在ofdm中起到了很好的效果。
-In modern wireless communication technologies, spread spectrum communication is a kind of strong anti-jamming technology, the performance of orthogonal frequency division multiplexing (OFDM) is a kind of high data rate and spectrum efficiency, and can be effective against frequency selective fading of multi-carrier modulation technology, and combine the two build system is bound to further improve the system s anti-interference and decay resistance, and study the combining technology also gradually become a hot spot in the field of wireless communications. With the development of 3 g, the upcoming LTE will also use OFDM (orthogonal frequency division multiplexing) technology. Platform: |
Size: 489472 |
Author:wfyan |
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Description: ofdm仿真，用matlab仿真实现ofdm，为初学者提供一条道路(The proposed secret data embedding and extraction in
OFDM is shown in figure 1.In order to achieve higher data
rate, the serial data stream bits are converted in to parallel data
output bits. Then the modulation schemes can be BPSK,
QPSK or QAM, which in turn assigns the complex data
points. The orthogonality between subcarriers is maintained
by IFFT and FFT pairs which also transforms frequency
domain components to time domain and vice versa. 64 point
IFFT is used in this methodology.) Platform: |
Size: 30720 |
Author:haitao15 |
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Search - data rate in OFDM