Description:
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. Platform: |
Size: 1421 |
Author:george |
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Description: This paper examines the asymptotic (large sample) performance
of a family of non-data aided feedforward (NDA FF) nonlinear
least-squares (NLS) type carrier frequency estimators for burst-mode
phase shift keying (PSK) modulations transmitted through AWGN and
flat Ricean-fading channels. The asymptotic performance of these estimators
is established in closed-form expression and compared with the
modified Cram`er-Rao bound (MCRB). A best linear unbiased estimator
(BLUE), which exhibits the lowest asymptotic variance within the family
of NDA FF NLS-type estimators, is also proposed. Platform: |
Size: 164864 |
Author:吴大亨 |
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Description:
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.-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. Platform: |
Size: 1024 |
Author:george |
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Description: 利用Channel Equalizer公式與附件main.m等程式，並選擇Flat=0之模式(該模式為Frequency Selective Fading)及產生Doppler = 500 Hz之Rayleigh fading Channel，利用已知Channel Parameters (rcos, rsin) 增修接收機之Channel Equalizer程式-Channel Equalizer using the formula and accessories main.m other programs, and select the Flat = 0 of the mode (the mode for the Frequency Selective Fading) and generate Doppler = 500 Hz of the Rayleigh fading Channel, the use of a known Channel Parameters (rcos, rsin) Upgrading receiver of the Channel Equalizer program Platform: |
Size: 5120 |
Author:Jason |
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Description: 对3条固定路径的AWGN多径信道中的QPSK系统进行BER性能仿真（不同p和delay 的取值来分别定义莱斯（瑞利）平坦衰落信道、莱斯（瑞利）频率选择性衰落信道).-For three fixed-path multipath AWGN channel of the QPSK system BER performance simulation (different values for p and the delay are defined Rice (Rayleigh) flat fading channel, Rice (Rayleigh) frequency-selective fading channels ). Platform: |
Size: 8192 |
Author:minmin |
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Description: The code below creates a frequency-flat Rayleigh fading channel object and uses it to process a DBPSK signal consisting of a single vector. Notice that the example uses filter before awgn this is the recommended sequence to use when you combine fading with AWGN -The code below creates a frequency-flat Rayleigh fading channel object and uses it to process a DBPSK signal consisting of a single vector. Notice that the example uses filter before awgn this is the recommended sequence to use when you combine fading with AWGN Platform: |
Size: 1024 |
Author:Ahsan Ali |
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Description: 要求对有3条固定路径的AWGN多径信道中的QPSK系统进行BER性能仿真，并与在理想的AWGN信道中同样系统的BER性能进行比较。熟悉瑞利平坦衰落、莱斯平坦衰落与频率选择性衰落的特点，比较这些衰落信道的误码率。-Required to have three fixed-path AWGN multipath channels of QPSK system BER performance simulation, and in an ideal AWGN channel with the same system BER performance comparison. Familiar with the Rayleigh flat fading, Rice flat fading and frequency selective fading characteristics, compare the bit error rate fading channel. Platform: |
Size: 1024 |
Author:沈岗 |
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Description: 文章根据频率选择性衰落信道的抽头延迟线模型，将针对平坦衰落信道的CS(周期平稳过程理论)频偏盲估计
算法扩展到了频率选择性衰落信道，并通过仿真证明这种扩展是可行的.仿真结果还表明CS算法不仅有好的抗平
坦衰落能力，而且有很好的杭频率选择性衰落性能.-Article according to frequency selective fading channel tap delay line model, the flat fading channel for CS (cycle stationary process theory) Frequency Offset Estimation Algorithm extended to frequency selective fading channel, and simulation prove that expansion is feasible. Simulation The results also show that the CS algorithm not only has good ability of anti-flat fading, and have a good hang frequency selective fading performance. Platform: |
Size: 324608 |
Author:motonula |
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Description: Ajey, S., B. Srivalli, et al. (2010). On performance of MIMO-OFDM based LTE systems. Wireless Communication and Sensor Computing, 2010. ICWCSC 2010. International Conference on.
4G wireless systems predominately employ multiple input multiple output (MIMO) with an orthogonal frequency division multiplexing (OFDM) system. Like other 4G systems long term evolution (LTE) also employs MIMO-OFDM physical layer. MIMO helps in increasing the throughput whereas OFDM converts a frequency selective fading channel to multiple flat fading sub-channels facilitating easy equalization. It is proposed that LTE system should mandatorily support 2Ã — 2 MIMO setup. Our paper focuses on the performance of such a LTE system with two transmit antennas and two receive antennas in a frequency selective fading environment. Platform: |
Size: 311296 |
Author:Lakmali |
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Description: Though the total channel is a frequency selective channel, the channel experienced by each subcarrier in an OFDM system is a flat fading channel with each subcarrier experiencing independent Rayleigh fading. Platform: |
Size: 2048 |
Author:azer |
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Description: qpsk仿真下面是该例子的源程序，P0、P1、P2分别是LOS路径和两条延迟瑞利分量的相对功率级。当p0=0且delay！=0时为瑞利频率选择性衰落，delay==0时为瑞利平坦衰落。-Here is the example qpsk simulation source, P0, P1, P2 are the LOS path Rayleigh component and two delayed relative power level. When p0 = 0 and the delay! = 0 for the Rayleigh frequency selective fading, delay == 0 when Rayleigh flat fading. Platform: |
Size: 4096 |
Author:suenxiaoda |
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Description: the use of coherent space-frequency coding in orthogonal frequency division multiplexing (OFDM)-based frequency-selective multiple-input multiple-output (MIMO) antenna fading channels has been proposed. Acquiring knowledge of the fading coefficients in a MIMO channel is already very challenging in the frequency-flat (fast) fading case. In the frequency-selective case, this task becomes significantly more difficult due to the presence of multiple paths, which results in an increased number of parameters to be estimated. In this paper, we address code design for noncoherent frequency-selective MIMO-OFDM fading links, where neither the transmitter nor the receiver knows the channel. We derive the code design criteria Platform: |
Size: 32768 |
Author:sourov |
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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: OFDM(Orthogonal Frequency Division Multiplexing)即正交频分复用技术，实际上OFDM是MCM Multi-CarrierModulation，多载波调制的一种。其主要思想是：将信道分成若干正交子信道，将高速数据信号转换成并行的低速子数据流，调制到在每个子信道上进行传输。正交信号可以通过在接收端采用相关技术来分开，这样可以减少子信道之间的相互干扰 ICI 。每个子信道上的信号带宽小于信道的相关带宽，因此每个子信道上的可以看成平坦性衰落，从而可以消除码间串扰。而且由于每个子信道的带宽仅仅是原信道带宽的一小部分，信道均衡变得相对容易。-OFDM (Orthogonal Frequency Division Multiplexing) that is orthogonal frequency division multiplexing, OFDM is actually MCM Multi-CarrierModulation, a multi-carrier modulation. The main idea is: The channel is divided into a number of orthogonal sub-channel, high-speed data signal into parallel low-speed data streams, modulated to be transmitted on each subchannel. Quadrature signal at the receiving end can be separated using technologies, which can reduce the mutual interference between ICI subchannels. Signal is less than the bandwidth of each sub-channel coherence bandwidth of the channel, each subchannel can be regarded as flat fading, which can eliminate inter-symbol interference. And because the bandwidth of each subchannel is only a small part of the original channel bandwidth, channel equalization becomes relatively easy. Platform: |
Size: 321536 |
Author:mixa |
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Description: OFDM(Orthogonal Frequency Division Multiplexing)即正交频分复用技术，实际上OFDM是多载波调制的一种。其主要思想是：将信道分成若干正交子信道，将高速数据信号转换成并行的低速子数据流，调制到在每个子信道上进行传输。正交信号可以通过在接收端采用相关技术来分开，这样可以减少子信道之间的相互干扰 ICI 。每个子信道上的信号带宽小于信道的相关带宽，因此每个子信道上的可以看成平坦性衰落，从而可以消除符号间干扰。而且由于每个子信道的带宽仅仅是原信道带宽的一小部分，信道均衡变得相对容易。-OFDM (Orthogonal Frequency Division Multiplexing) that is orthogonal frequency division multiplexing, in fact, is a multi-carrier OFDM modulation. The main idea is: The channel is divided into a number of orthogonal sub-channel, high-speed data signal into parallel low-speed data streams, modulated to be transmitted on each subchannel. Quadrature signal at the receiving end can be separated using technologies, which can reduce the mutual interference between ICI subchannels. The signal bandwidth of each subchannel is less than the channel coherence bandwidth, and therefore can be regarded as flat fading on each sub-channel, thereby eliminating inter-symbol interference. And because the bandwidth of each subchannel is only a small part of the original channel bandwidth, channel equalization becomes relatively easy. Platform: |
Size: 2048 |
Author:刘金星 |
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Description: 在OFDM系统
中，宽带信道被分割相互重叠的窄带子信道，如果各子信道
的带宽比信道的相干带宽要小，那么信号传输就有可能在无
频率选择性衰落或者平坦衰落的信道进行。-In OFDM system
The wideband channel is divided into narrowband sub-overlapping, if each sub-
The bandwidth is less than the coherence bandwidth of the channel, the signal transmission is possible without
Frequency selective fading or flat fading channels. Platform: |
Size: 272384 |
Author:liufang |
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Description: Orthogonal STBC [4], [5] has been designed to achieve the spatial diversity offered by multiple transmit and/or receive antennas. The STBC
schemes proposed in [4] and [5] are designed for flat-fading channels,
which lead to a performance degradation in time- and frequency-selective channels. Our goal is to design efficient STBC schemes to counteract the effects of doubly-selective channels. The basic idea of the
proposed STBC for a 21 system is to multiplex the data sequence
in two data subsequences and to generate two orthogonal full-diversity
subchannels over doubly-selective channels. Then, we apply a scheme
that is similar to the Alamouti code. Platform: |
Size: 1024 |
Author:phuong |
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Search - frequency flat fading