Description: 硕士学位论文:LDPC码在瑞利衰落信道中的性能分析
信道编码技术可以带来编码增益，节省宝贵的功率资源，己经成为现代数字
通信系统中必不可少的关键技术。LDPC码采用低复杂度的迭代译码算法，且具有
逼近香农限的性能.由于LDPC码具有诸多优点，它在信息可靠传输中的良好应
用前景己经引起学术界和rr业界的高度重视，成为当今信道编码领域最受瞩目的
研究热点之一。
本文主要探讨了LDPC码在瑞利衰落信道中的性能，基于LDPC码的分组空
时码系统，以及基于LDPC码的正交频分复用系统.-master's degree thesis : LDPC codes in Rayleigh fading channels Performance Analysis channel coding technology can bring coding gain, Power saving valuable resources have become modern digital communication systems essential to the critical technologies. LDPC low complexity of the iterative decoding algorithm, having approximation Shannon limit performance. Because LDPC has many advantages, It reliable transmission of information in the application of good prospects has been caused rr academia and industry are taking, become the channel coding areas of the most watched one of the hot spots. This paper mainly discusses the LDPC Rayleigh fading channels in the performance Based on LDPC a space-time coding system, and based on LDPC orthogonal frequency division multiplexing system. Platform: |
Size: 2362694 |
Author:daniel |
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Description: 硕士学位论文:LDPC码在瑞利衰落信道中的性能分析
信道编码技术可以带来编码增益，节省宝贵的功率资源，己经成为现代数字
通信系统中必不可少的关键技术。LDPC码采用低复杂度的迭代译码算法，且具有
逼近香农限的性能.由于LDPC码具有诸多优点，它在信息可靠传输中的良好应
用前景己经引起学术界和rr业界的高度重视，成为当今信道编码领域最受瞩目的
研究热点之一。
本文主要探讨了LDPC码在瑞利衰落信道中的性能，基于LDPC码的分组空
时码系统，以及基于LDPC码的正交频分复用系统.-master's degree thesis : LDPC codes in Rayleigh fading channels Performance Analysis channel coding technology can bring coding gain, Power saving valuable resources have become modern digital communication systems essential to the critical technologies. LDPC low complexity of the iterative decoding algorithm, having approximation Shannon limit performance. Because LDPC has many advantages, It reliable transmission of information in the application of good prospects has been caused rr academia and industry are taking, become the channel coding areas of the most watched one of the hot spots. This paper mainly discusses the LDPC Rayleigh fading channels in the performance Based on LDPC a space-time coding system, and based on LDPC orthogonal frequency division multiplexing system. Platform: |
Size: 2362368 |
Author:daniel |
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Description: 完成对发送数据符号的空时编码 实现空间复用和分集增益-Send data to complete the symbol space-time coding and spatial multiplexing diversity gain Platform: |
Size: 2048 |
Author:林琳 |
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Description: 在FHP3350和FHP3450是低成本，高性能，
电压反馈为视频应用而设计的放大器。
这些三和四放大器仅消耗供应三点六毫安
当前每通道可以驱动双（75？）视频功能
负载，同时提供0.1dB的增益平坦度至30MHz。
消费类视频应用也将受益于低
差分增益0.07％和0.03？差分相位误差。那个
FHP3350提供三种，可以成为一个高投入产出
阻抗禁用状态，以便复用或视频
功耗降到最低。
这些放大器的设计工作从5V（± 2.5V的），以
12V的（± 6V的）用品。的产出范围内摆动，或为1.3V
电源电压适应单一5V电源，视频信号。
FHP3450的FHP3350和设计上的互补性
双极工艺制造。他们提供的全功率带宽为210MHz
和1,100 V /μs的压摆率为± 5V电源电压。那个
高性能，低功率和出色的
视频性能使这些放大器以及在适合使用
许多数字消费类视频设备以及许多
通用高速应用-The FHP3350 and FHP3450 are low cost, high performance,
voltage feedback amplifiers designed for video applications.
These triple and quad amplifiers consume only 3.6mA of supply
current per channel and are capable of driving dual (75?) video
loads while providing 0.1dB of gain flatness to 30MHz.
Consumer video applications will also benefit from their low
0.07 differential gain and 0.03? differential phase errors. The
FHP3350 offers three outputs that can be put into a high
impedance disable state to allow for video multiplexing or
minimize power consumption.
These amplifiers are designed to operate from 5V (±2.5V) to
12V (±6V) supplies. The outputs swing to within 1.3V of either
supply rail to accommodate video signals on a single 5V supply.
The FHP3350 and FHP3450 are designed on a complementary
bipolar process. They provide 210MHz of full power bandwidth
and 1,100V/μs of slew rate at a supply voltage of ±5V. The
combination of high performance, low power, and e Platform: |
Size: 743424 |
Author:wangyuli |
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Description: This demo introduces Matched Filter in CDMA system schemes wherein the data stream is subdivided into independent sub-streams, one for each transmit antenna employed. As a consequence, they provide a multiplexing gain and do not require explicit orthogonalization as needed for space-time block coding. Platform: |
Size: 1024 |
Author:KidQn |
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Description: MIMO OFDM 技术将成为第4 代移动通信系统的关键技术, 因MIMO OFDM 对时间和频率偏移非常敏感,
因此MIMO OFDM 同步显得尤为重要。提出了一种新的MIMO OFDM 定时同步和频偏同步技术。以GCL 序列为基础设
计了一个新的符合MIMO OFDM 同步技术的导频序列, 通过对该导频序列进行2 次相关得到频率估计, 并将所得频率
运用到定时同步中, 得到更为准确的时间估计。仿真结果表明, 在相同的信噪比情况下, 该方法可以使得系统的误码
率和帧传送误码率相对传统方法得到进一步减小。-MIMO OFDM will become a key technology of the fourth generation mobile communications system. However, MIMO OFDM is
sensitive to the CFO and timing synchronization, so the MIMO OFDM synchronization technology is very important. This paper proposes an
accurate technique for timing and frequency synchronization of multiple input multiple output ( MIMO ) orthogonal frequency division
multiplexing ( OFDM) systems. The technique derives a new preamble signal based on GCL sequences, according with the MIMJO OFDM
synchronization. The carrier frequency offset ( CFO) estimation is obtained through taking double correlation operations on the preamble signal,
and used in the timing synchronization to gain accurate time estimation. The simulation results show that at the same SNR, the proposed method
can reduce the BER and the frame transmission BER of the system compared to the conventional method. Platform: |
Size: 408576 |
Author:蜡笔 |
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Description: the achievable rate of a K-user
interference channel with single antenna at individual node is
studied. Interference alignment and zero forcing are applied at
the transmitter and receiver, respectively. It is well known from
the paper [1] of Cadambe and Jafar that a multiplexing gain
(degrees of freedom) of K/2 is achievable. We propose two new
pre-coding methods and study how they enhance the achievable
rate in terms of the high SNR offset, while maintain the optimality
of degree of freedom the Cadambe-Jafar scheme achieved.-the achievable rate of a K-user
interference channel with single antenna at individual node is
studied. Interference alignment and zero forcing are applied at
the transmitter and receiver, respectively. It is well known from
the paper [1] of Cadambe and Jafar that a multiplexing gain
(degrees of freedom) of K/2 is achievable. We propose two new
pre-coding methods and study how they enhance the achievable
rate in terms of the high SNR offset, while maintain the optimality
of degree of freedom the Cadambe-Jafar scheme achieved. Platform: |
Size: 219136 |
Author:mohamed |
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Description: A 2x2 multiple-input multiple-output (MIMO) architecture
using dual-polarized antennas (DPAs) is considered
with orthogonal frequency division multiplexing (OFDM). The
performance of DPAs is evaluated for adaptive polarization
(AP) transmission techniques in time-varying multipath channels
impaired by polarization mode dispersion (PMD) and
polarization-dependent loss (PDL). AP transmission techniques
considered include power gain maximization, polarization dispersion
minimization for interference avoidance, polarization
multiplexing with waterfilling, and a suboptimal multiplexing
strategy that enables direct recovery of the polarization multiplexed
streams, thereby simplifying the design of the receiver.
Measured time-varying dual-polarized channel realizations from
mobile-to-mobile experiments are used to estimate the capacity,
diversity, and interference avoidance performance of the adaptive
approaches. Platform: |
Size: 1401856 |
Author:room |
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Description: THIS CODE SIMULATE A COMPLETE MIMO SYSTEM (MULTIPLEXING GAIN),AND AN ADDITIVE 1/2 FEC WAS USED ,THE RESULTS COMPARED WITH MMSE DETECTOR WITHOUT FEC,THE VITERBI DECODER WAS USED AT THE RECEIVER
Platform: |
Size: 1024 |
Author:kemo |
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Description: In this letter, we propose a simple orthogonal
frequency-division multiplexing (OFDM) scheme for an asynchronous cooperative system, where OFDM is implemented at the source node, and time-reversion and complex conjugation are implemented at the relay nodes. The cyclic prefix (CP) at the source node is used for combating the timing errors the relay nodes.
In this scheme, the received signals at the destination node have the Alamouti code structure on each subcarrier, and thus, it has
the fast symbol-wise ML decoding. It should be emphasized that the relay nodes only need to implement the time-reversion, some sign changes plus to minus, and/or the complex conjugation to the received signals, and no IDFT or DFT operation is needed.It is shown that this simple scheme achieves second-order diversity
gain without the synchronization requirement at the relay nodes.
Index Terms—Alamouti code, asynchronous cooperative diversity,
orthogonal frequency-division multiplexing (OFDM).-In this letter, we propose a simple orthogonal
frequency-division multiplexing (OFDM) scheme for an asynchronous cooperative system, where OFDM is implemented at the source node, and time-reversion and complex conjugation are implemented at the relay nodes. The cyclic prefix (CP) at the source node is used for combating the timing errors the relay nodes.
In this scheme, the received signals at the destination node have the Alamouti code structure on each subcarrier, and thus, it has
the fast symbol-wise ML decoding. It should be emphasized that the relay nodes only need to implement the time-reversion, some sign changes plus to minus, and/or the complex conjugation to the received signals, and no IDFT or DFT operation is needed.It is shown that this simple scheme achieves second-order diversity
gain without the synchronization requirement at the relay nodes.
Index Terms—Alamouti code, asynchronous cooperative diversity,
orthogonal frequency-division multiplexing (OFDM). Platform: |
Size: 106496 |
Author:Hakim |
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Description: 大规模MIMO系统中，发射端、接收端采用QPSK调制、解码方式，使用Alamouti预编码算法，经过瑞丽衰落信道的复用性能matlab仿真。-The simulation of multiplexing gain that signals which are moduled by QPSK transmitt via Rayleigh channel in a massive MIMO system. Platform: |
Size: 4096 |
Author:李瑜锋 |
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Description: Abstract—A generalised spatial modulation (SM) scheme with
multiple active transmit antennas, named as multiple activespatial
modulation (MA-SM), is proposed in this paper. By allowing
multiple transmitting antennas in the SM system to transmit
different symbols at the same time instant, MA-SM takes advantages
of the low complexity of SM and high multiplexing gain of
Vertical-Bell Lab Layered Space-Time (V-BLAST) system. In the
MA-SM system, the transmitted symbols are mapped into a high
dimensional constellation space including the spatial dimension.
The general principle for designing the efficient MA-SM for
arbitrary number of transmit antennas and modulation scheme
is presented. Moreover, a near-optimal detection Platform: |
Size: 396288 |
Author:senthil |
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Description: he fabrication and performaince of a semiconductor
optical amplifier for wavelength conversion in subcarrier
multiplexed system is described. The amplifier is of the buried
facet design and has p o ~ a r ~ ~ a ~anido nre flectivity gain ripple of
carrier multiplexing, multiple 50-Mb/s
data streams at a wave~ength of 1.553 pm are injected into the
amplifier. The gain y of the amplifier transfers the
data to a dierent w of light siniultaneously injected
into the amplifier. Error free retri of subcarrier multiplexed
data has been de~ons~ratefodr the wavelength converted output.
The small signal bandwidth of the wavelength conversion process
is 5 GHz.-he fabrication and performaince of a semiconductor
optical amplifier for wavelength conversion in subcarrier
multiplexed system is described. The amplifier is of the buried
facet design and has p o ~ a r ~ ~ a ~anido nre flectivity gain ripple of
carrier multiplexing, multiple 50-Mb/s
data streams at a wave~ength of 1.553 pm are injected into the
amplifier. The gain y of the amplifier transfers the
data to a dierent w of light siniultaneously injected
into the amplifier. Error free retri of subcarrier multiplexed
data has been de~ons~ratefodr the wavelength converted output.
The small signal bandwidth of the wavelength conversion process
is 5 GHz. Platform: |
Size: 378880 |
Author:wail |
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Description: In this letter, we propose a simple orthogonal
frequency-division multiplexing (OFDM) scheme for an asynchronous cooperative system, where OFDM is implemented at the source node, and time-reversion and complex conjugation are implemented at the relay nodes. The cyclic prefix (CP) at the source node is used for combating the timing errors the relay nodes.
In this scheme, the received signals at the destination node have the Alamouti code structure on each subcarrier, and thus, it has
the fast symbol-wise ML decoding. It should be emphasized that the relay nodes only need to implement the time-reversion, some sign changes plus to minus, and/or the complex conjugation to the received signals, and no IDFT or DFT operation is needed.It is shown that this simple scheme achieves second-order diversity
gain without the synchronization requirement at the relay nodes.-In this letter, we propose a simple orthogonal
frequency-division multiplexing (OFDM) scheme for an asynchronous cooperative system, where OFDM is implemented at the source node, and time-reversion and complex conjugation are implemented at the relay nodes. The cyclic prefix (CP) at the source node is used for combating the timing errors the relay nodes.
In this scheme, the received signals at the destination node have the Alamouti code structure on each subcarrier, and thus, it has
the fast symbol-wise ML decoding. It should be emphasized that the relay nodes only need to implement the time-reversion, some sign changes plus to minus, and/or the complex conjugation to the received signals, and no IDFT or DFT operation is needed.It is shown that this simple scheme achieves second-order diversity
gain without the synchronization requirement at the relay nodes. Platform: |
Size: 107520 |
Author:Hakim |
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Description: MU-MIMO is widely considered a key technology
for system capacity improvement in modern
wireless networks. In contrast to
SU-MIMO, where the spatial multiplexing gain
is confined to a single user, MU-MIMO allows
multiple users to be co-scheduled on the same
time-frequency resources to exploit this gain
among two or more UE units. This is particularly
beneficial as high-rank SU-MIMO transmission
is often limited by the number of
antennas and antenna design constraints at the
user end, whereas high-rank transmission using
MU-MIMO is more feasible due to the scattered
user distribution.
It is well known that the information theoretic
optimal MU-MIMO scheme is dirty paper
coding (DPC), which unfortunately is a nonlinear/
non-causal beamforming scheme and therefore
unrealistic in real-life applications. From a
practical deployment point of view, the most Platform: |
Size: 407552 |
Author:nebiyu |
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Description: Low-density parity-check (LDPC) coded optical orthogonal frequency division multiplexing (OFDM) is shown to significantly outperform other coded OFDM over the fading channel in terms of both coding gain and spectral efficiency. Platform: |
Size: 662776 |
Author:mustafa1970 |
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Search - multiplexing gain