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Description: A major challenge to MIMO-OFDM systems is how to obtain the channel state in-
formation accurately and promptly for coherent detection of information symbols and
channel synchronization.,A major challenge to MIMO-OFDM systems is how to obtain the channel state in-
formation accurately and promptly for coherent detection of information symbols and
channel synchronization.
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Size: 41984 |
Author: Nirupa |
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Description: A major challenge to MIMO-OFDM systems is how to obtain the channel state in-
formation accurately and promptly for coherent detection of information symbols and
channel synchronization.,A major challenge to MIMO-OFDM systems is how to obtain the channel state in-
formation accurately and promptly for coherent detection of information symbols and
channel synchronization.
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Size: 964608 |
Author: Nirupa |
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Description: ofdm程序4QAM调制。 子载波数 128
位数/ 符号 2
符号数/ 载波 1000
训练符号数 0
循环前缀长度 8
调制方式 4-QAM
多径信道数 3
IFFT Size 128
信道最大时延 2-ofdm program 4QAM modulation. Subcarriers median number of 128 /2 Symbol Symbol/carrier cyclic prefix length of the number of training symbols of 1000 0 8 modulation mode 4-QAM multi-path channel number 3 the IFFT Size 128 channel maximum delay
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Size: 2048 |
Author: xiaoxi |
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Description: Selective mapping algorithm is proposed to reduce the peak-to-average power ration (PAPR) in MIMO-OFDM system.
It is proved that the conjugate symbols on two antennas have the same PAPR property with orthogonal space-time block coded (STBC). By using the characteristic, the computational
complexity cost and the side information (SI) is significantly
reduced compared with the concurrent SLM algorithm.
Simulation results demonstrate that the performance of the proposed algorithm outperforms the conventional concurrent
SLM algorithm.
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Size: 117760 |
Author: redami |
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Description: 这个matlab程序主要介绍的而是OFDM调制过程，主要设置了符号数，载波数，循环前缀大小，对信号进行了IFFT变换，串并转换等。-The matlab program introduces the OFDM modulation process but the main set of symbols, the number of carriers, cyclic prefix size, the signal of the IFFT transform, string and conversion
Platform: |
Size: 1024 |
Author: sunjing |
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Description: Three Timing Synchronization Methods Based on Two Same Preambles for OFDM Systems
The purpose of this paper is to propose two fast timing synchronization methods of OFDM System which has two preamble symbols, the two preamble symbols are used for SNR estimation for OFDM systems. The synchronization techniques are examined in Multipath fading environments for comparison. The results of the performance
comparison are presented in terms of mean obtained by simulations.
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Size: 268288 |
Author: Mohamed |
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Description: 简化的OFDM系统仿真，其中暂未考虑扰码和卷积码，物理层参数采用802.11a参数，1个长训练符号与6个OFDM数据符号构成1帧，信道为单径rayleigh衰落信道，其中最大多普勒频移为100Hz，信噪比0-30dB，调制方式为QPSK和16-QAM。-Simplified OFDM system simulation, which yet consider scrambling and convolution codes, physical layer parameters using 802.11a parameters, a long training symbols and six OFDM data symbols constitute a channel for single-path rayleigh fading channel, one of the largest Doppler shift is 100Hz, the SNR 0-30dB, the modulation scheme is QPSK and 16-QAM.
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Size: 3072 |
Author: PengJ |
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Description: Simulation and performance analysis of OFDM with different modulation techniques
A special case of multicarrier transmission is Orthogonal Frequency Division Multiplexing (OFDM).In which single data stream is transmitted over a number of lower rate subcarriers. In July 1998 a new 5-GHz standard, targeting a range of data stream 6 up to 54 Mbps was standardized by IEEE keeping the basis as OFDM although its use was limited to continuous transmission. High throughput and high transmission rate can be obtained in wireless communication through concept of parallel transmission of signals. OFDM is one of the techniques of parallel symbol transmission to achieve better transmission quality. The idea of OFDM is to split the total transmission bandwidth into a number of orthogonal subcarriers in order to transmit the symbols using these subcarriers in parallel.-Simulation and performance analysis of OFDM with different modulation techniques
A special case of multicarrier transmission is Orthogonal Frequency Division Multiplexing (OFDM).In which single data stream is transmitted over a number of lower rate subcarriers. In July 1998 a new 5-GHz standard, targeting a range of data stream 6 up to 54 Mbps was standardized by IEEE keeping the basis as OFDM although its use was limited to continuous transmission. High throughput and high transmission rate can be obtained in wireless communication through concept of parallel transmission of signals. OFDM is one of the techniques of parallel symbol transmission to achieve better transmission quality. The idea of OFDM is to split the total transmission bandwidth into a number of orthogonal subcarriers in order to transmit the symbols using these subcarriers in parallel.
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Size: 373760 |
Author: Mohamed |
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Description: IEEE 802.11a系统OFDM仿真。假设OFDM系统物理层采用802.11a系统物理层参数，其中，1个长训练符号与6个OFDM数据符号构成1帧，信道为单径瑞丽衰落信道，接收端采用理想信道估计和利用训练符号进行信道估计时的误比特性能-IEEE 802.11a system OFDM simulation
Assuming that the OFDM system physical layer uses the 802.11a physical layer parameters, among them, 1 long training symbols and 6 OFDM data symbol consisted of 1 frames, the channel into a single path Ruili fading channel, the receiver uses the ideal channel estimation and utilizes the training symbols to estimate channel bit error performance of the
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Size: 2048 |
Author: 方源 |
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Description: ofdm channel estimation based on pilot symbols
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Size: 4096 |
Author: mohamad |
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Description: frequency division multiplexing (OFDM) is used extensively in broadband wired and wireless communication systems because it is an effective solution to intersymbol interference (ISI) caused by a dispersive channel. This becomes increasingly important as data rates increase to the point where, when conventional serial modulation schemes like quadrature amplitude modulation (QAM) or NRZ are used, the received signal at any time depends on multiple transmitted symbols. In this case the complexity of equalization in serial schemes which use time domain equalization rises rapidly. In contrast, the complexity of OFDM, and of systems using serial modulation and frequency domain equalization, scale well as data rates and dispersion increase. [1]–[3]. A second major advantage of OFDM is that it transfers the complexity of transmitters and receivers the analog to the digital domain-frequency division multiplexing (OFDM) is used extensively in broadband wired and wireless communication systems because it is an effective solution to intersymbol interference (ISI) caused by a dispersive channel. This becomes increasingly important as data rates increase to the point where, when conventional serial modulation schemes like quadrature amplitude modulation (QAM) or NRZ are used, the received signal at any time depends on multiple transmitted symbols. In this case the complexity of equalization in serial schemes which use time domain equalization rises rapidly. In contrast, the complexity of OFDM, and of systems using serial modulation and frequency domain equalization, scale well as data rates and dispersion increase. [1]–[3]. A second major advantage of OFDM is that it transfers the complexity of transmitters and receivers the analog to the digital domain
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Size: 415744 |
Author: kartick |
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Description: A subspace-based blind method is proposed for estimating
the channel responses of a multiuser and multiantenna orthogonal
frequency division multiplexing (OFDM) uplink system.
It gives estimations to all channel responses subject to a scalar matrix
ambiguity and does not need precise channel order information
(only an upper bound for the orders is required). Furthermore,
the scalar ambiguity matrix can be easily resolved by using only
one pilot OFDM block, given that the number of users is smaller
than the number of symbols in the pilot symbol block. Equalization
methods are discussed based on the estimated channels. By using
partial knowledge of the channels, a multipath subspace method is
proposed that reduces the computational complexity. Simulations
show that the methods are effective and robust.
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Size: 286720 |
Author: Moyad |
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Description: 实现基于STBC的MIMO_OFDM通信系统在不同信噪比情况下接收端的误比特率的仿真。发射端包括基于基带调制、空时编码、导频插入、IFFT、串并合并以及添加循环前缀；接收端包括去除循环前缀、取出导频估计信道、FFT运算以及并串合并，空时解码等。仿真中采用QPSK、空时编码采用4*3的复正交空时编码矩阵。OFDM子载波数为100，每个子载波传输66个符号，每个符号2比特。IFFT长度为512个符号。发射天线为3个接收天线为2个。(The BER simulation of MIMO_OFDM communication system based on STBC under different SNR is realized. The transmitter includes baseband modulation, space-time coding, pilot insertion, IFFT, serial-parallel combination and adding cyclic prefix; the receiver includes removing cyclic prefix, extracting pilot estimation channel, FFT operation, parallel-serial combination, space-time decoding, etc. The complex orthogonal space-time coding matrix is used in QPSK and space time coding in 4*3. The number of OFDM subcarriers is 100, and each subcarrier transfers 66 symbols with 2 bits per symbol. IFFT is 512 symbols in length. The transmitting antenna is 3 receiving antennas, 2.)
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Size: 3072 |
Author: guokeDz |
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