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Description: Frequency Domain Blind MIMO System
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Size: 10240 |
Author: pkumar |
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Description: 采用多天线的认知无线电系统相对于单天线认知无线电系统，既有传统的资源（频域，时域，码域），又有空域资源。本文研究基于博弈论的有限反馈认知MIMO系统的资源分配，涉及发射功率、空域（采用波束成形）和反馈速率等资源的分配。利用有限的反馈信道反馈量化的信道状态信息(CSI)，基于量化CSI，本文主要研究联合功率分配与波束成形优化、次用户（认知用户或非授权用户）反馈速率控制、联合功率分配与反馈速率控制等相关资源分配问题。-Multi-antenna cognitive radio system with respect to a single antenna cognitive radio systems, both traditional resource (frequency domain, time domain, code domain), there airspace resources. In this paper, a limited resource allocation game theory of cognitive MIMO system based on feedback, involving the launch distribution power, airspace (using beam-forming) and feedback rate and other resources. With limited feedback channel feedback quantized channel state information (CSI), based on quantified CSI, this paper studies the joint power allocation and beamforming optimization, secondary users (cognitive user or unauthorized user) feedback rate control, joint power allocation and feedback rate control and other issues related to resource allocation.
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Size: 52224 |
Author: sunjing |
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Description: If SDMA is used on the downlink of a multi-user MIMO system,
either long-term or short-term channel state information
has to be available at the base station (BS) to faciliate the joint
precoding of the signals intended for the different users. Precoding
is used to efficiently eliminate or suppressmulti-user interference
(MUI) via beamforming or by using ”dirty-paper”
codes. It also allows us to performmost of the complex processing
at the BS which leads to a simplification of the mobile terminals.
In this paper, we provide an overview of efficient linear
and non-linear precoding techniques formulti-userMIMO
systems. The performance of these techniques is assessed via
simulations on statistical channelmodels, and on channels generated
by the IlmProp, a geometry-based channel model that
generates realistic correlations in space, time, and frequency.
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Size: 74752 |
Author: ImranKhan |
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Description: Application of spread spectrum for satellite land mobile systems is difficult in satellite link because of synchronization and
providing code or considerable Doppler shift. This is particularly high for LEO satellites. So that, a Doppler shift carrying a
frequency in band S can reach to several tens of kHz. To estimate and compensate Doppler, a CW pilot carrier is used. The
aim of this study is simulate Doppler frequency estimation using MIMO-OFDM technique. Finally, the proposed algorithm is
compared to MMSE algorithm in order to insure its performance.
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Size: 136192 |
Author: Neo Matrix |
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Description: 着重研究Turbo编译码技术及其在均衡中的应用，以及在频率选择性MIMO信道中Turbo均衡的应用。-Turbo Decoding focuses on technology and its application in equilibrium, and the application of frequency-selective MIMO channel equalization in Turbo.
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Size: 2584576 |
Author: 天空若水 |
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Description: Multiple input multiple output orthogonal frequency division multiplexing (MIMO-OFDM) is very sensitive to the carrier frequency offset (CFO), which not only affects the channel estimation but also the selection of a minimum error probability based precoder for peak-to-average power ratio (PAPR) reduction such that the system performance will degrade. This paper presents the joint scheme of CFO) and channel estimation in the MIMO-OFDM systems with the minimum error probability based precoder for reducing PAPR. We provide the solution to eliminate the effects of ICI due to CFO mismatch for OFDM with space frequency block codes and spatial multiplexing, drive a generalized linear model and propose a non-iterative reduced complexity model. Our proposed scheme is effective in estimating and compensating for frequency-independent and frequency dependent transmit and receive ICI in the presence of a carrier frequency offset.-Multiple input multiple output orthogonal frequency division multiplexing (MIMO-OFDM) is very sensitive to the carrier frequency offset (CFO), which not only affects the channel estimation but also the selection of a minimum error probability based precoder for peak-to-average power ratio (PAPR) reduction such that the system performance will degrade. This paper presents the joint scheme of CFO) and channel estimation in the MIMO-OFDM systems with the minimum error probability based precoder for reducing PAPR. We provide the solution to eliminate the effects of ICI due to CFO mismatch for OFDM with space frequency block codes and spatial multiplexing, drive a generalized linear model and propose a non-iterative reduced complexity model. Our proposed scheme is effective in estimating and compensating for frequency-independent and frequency dependent transmit and receive ICI in the presence of a carrier frequency offset.
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Size: 1942528 |
Author: sivadeep |
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Description: Multiple input multiple output orthogonal frequency division multiplexing (MIMO-OFDM) is very sensitive to the carrier frequency offset (CFO), which not only affects the channel estimation but also the selection of a minimum error probability based precoder for peak-to-average power ratio (PAPR) reduction such that the system performance will degrade. This paper presents the joint scheme of CFO) and channel estimation in the MIMO-OFDM systems with the minimum error probability based precoder for reducing PAPR. We provide the solution to eliminate the effects of ICI due to CFO mismatch for OFDM with space frequency block codes and spatial multiplexing, drive a generalized linear model and propose a non-iterative reduced complexity model.-Multiple input multiple output orthogonal frequency division multiplexing (MIMO-OFDM) is very sensitive to the carrier frequency offset (CFO), which not only affects the channel estimation but also the selection of a minimum error probability based precoder for peak-to-average power ratio (PAPR) reduction such that the system performance will degrade. This paper presents the joint scheme of CFO) and channel estimation in the MIMO-OFDM systems with the minimum error probability based precoder for reducing PAPR. We provide the solution to eliminate the effects of ICI due to CFO mismatch for OFDM with space frequency block codes and spatial multiplexing, drive a generalized linear model and propose a non-iterative reduced complexity model.
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Size: 1024 |
Author: sivadeep |
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Description: MIMO-OFDM系统中一种改进的递归最小二乘(RLS)信道估计方法可以在不需要任何信道统计信息的前提下，利用前导训练序列和自适应遗忘因子对信道状态参数进行估计。-The modified recursion lest squares (RLS) channel estimation method exploits preamble training
sequences and adaptive forgetting factor to estimate channel state parameters without any prior statistics knowledge
of channel in multiple input multiple outputorthogonal frequency division multiplexing (MIMO-OFDM) systems.
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Size: 960512 |
Author: zhangjg |
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Description: This codes are for frequency selective fading channels for MIMO system. Both estimation and equalization are done using LS and MMSE estimation and ZF and MMSE equalization.
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Size: 2048 |
Author: manu |
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Description: Quasi-Orthogonal Space-Time-Frequency Trellis Codes for MIMO-OFDM Systems
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Size: 166912 |
Author: li |
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Description: UHF MIMO-RFID在Nakagami衰落信道下的性能分析-the reverse-link interrogation range
(RIR) of ultrahigh-frequency-band passive radio-frequency identification
(RFID) is analyzed for single-input and single-output
(SISO) and multiple-input and multiple-output (MIMO) systems
with maximal-ratio combining in the pinhole channel, where each
channel is modeled as an arbitrarily correlated Nakagami-m
distribution.
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Size: 365568 |
Author: 小红 |
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Description: ns STBC for purely time-selective channels by transforming the
time-selective channels into frequency-selective channels, and by
adjusting existing space–time code designs over frequency-selective
MIMO channels to collect joint space–Doppler gains over purely
time-selective MIMO channels. Further, [14] uses the ideas of [12] to
develop a space–time code that can achieve full space-delay-Doppler
diversity for any number of transmit–receive antennas. However, to
quantify the maximum Doppler diversity order [2], the above papers
rely on a parsimonious critically sampled complex-exponential basis
expansion model (CCE-BEM) for the underlying purely time-selective
or doubly-selective channels [16]. However, the CCE-BEM may have
a large modeling error under certain channel conditions
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Size: 1024 |
Author: phuong |
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Description: In this paper, we develop a novel STBC for multi-antenna transmissions over doubly-selective channels. The proposed STBC is designed
for a multiple-input single-output (MISO) system with two transmit
antennas and one receive antenna, i.e., a 2 1 system, but the ideas
can be extended to a general multiple-input multiple-output (MIMO)
system. The proposed technique can be interpreted as the extension
of the Alamouti code to doubly-selective channels, and relies on a
joint time–frequency reversal of the transmitted sequences.
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Size: 1024 |
Author: phuong |
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Description: Long-Term Evolution (LTE) is a new standard speci ed by 3GPP for fourth generation (4G)
wireless communications. LTE provides high spectral eciency, high peak data rates, short
round trip time, and frequency
exibility. It relies on the following technologies Orthog-
onal Frequency Division Multiplexing (OFDM) and Multiple-Input and Multiple- Output
(MIMO), robust channel coding, scheduling and link adaptation [1]. LTE is interoperable
with widely used technologies such as GPRS, WCDMA and HSPA, and this enables mobile
operators deploying LTE to provide a seamless service and multimode devices for customers.
Some companies have already launched commercial LTE networks, e.g., Verizon Wireless in
the United States and Vodafone in Europe.
Here,the throughput of LTE physical layer in downlink transmissions is carried out. The various steps like CRC,turbo coding, code block segmentation,scrambling, modulation and precoding are also carried out.-Long-Term Evolution (LTE) is a new standard speci ed by 3GPP for fourth generation (4G)
wireless communications. LTE provides high spectral eciency, high peak data rates, short
round trip time, and frequency
exibility. It relies on the following technologies Orthog-
onal Frequency Division Multiplexing (OFDM) and Multiple-Input and Multiple- Output
(MIMO), robust channel coding, scheduling and link adaptation [1]. LTE is interoperable
with widely used technologies such as GPRS, WCDMA and HSPA, and this enables mobile
operators deploying LTE to provide a seamless service and multimode devices for customers.
Some companies have already launched commercial LTE networks, e.g., Verizon Wireless in
the United States and Vodafone in Europe.
Here,the throughput of LTE physical layer in downlink transmissions is carried out. The various steps like CRC,turbo coding, code block segmentation,scrambling, modulation and precoding are also carried out.
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Size: 4096 |
Author: anju |
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Description: Long-Term Evolution (LTE) is a new standard speci ed by 3GPP for fourth generation (4G)
wireless communications. LTE provides high spectral eciency, high peak data rates, short
round trip time, and frequency
exibility. It relies on the following technologies Orthog-
onal Frequency Division Multiplexing (OFDM) and Multiple-Input and Multiple- Output
(MIMO), robust channel coding, scheduling and link adaptation.
This code tests for the throughput performance of LTE physical downlink shared channel-Long-Term Evolution (LTE) is a new standard speci ed by 3GPP for fourth generation (4G)
wireless communications. LTE provides high spectral eciency, high peak data rates, short
round trip time, and frequency
exibility. It relies on the following technologies Orthog-
onal Frequency Division Multiplexing (OFDM) and Multiple-Input and Multiple- Output
(MIMO), robust channel coding, scheduling and link adaptation.
This code tests for the throughput performance of LTE physical downlink shared channel
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Size: 5120 |
Author: anju |
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Description: 对统计MIMO 雷达提出了一种映
射搜索配对法来实现在不同观测通道中的目标距离延时和多普勒频率估计值的配对-To propose a statistical MIMO radar mapping
Radio search pairing method implemented in different target distances observation channel delay and Doppler frequency estimates pairing
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Size: 384000 |
Author: 言午 |
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Description: 基于IEEE802.11n MIMO-OFDM的时域同步和频域同步，经典算法和改进算法的对比，并且中英文均包含-Time domain based on IEEE802.11 n MIMO- OFDM synchronization and frequency synchronization, classic algorithms and the comparison of improved algorithm, and are included in both English and Chinese
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Size: 398336 |
Author: 李玉 |
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Description: MC-CDMA with SFBC
In the next subsections, we describe the architecture of an SFBC MIMO MC-CDMA transmitter, and define the basic terms related to the PAPR of the involved signals.
System model
In an MC-CDMA system, a block of M information symbols each active user are spread in the frequency domain into N = LM subcarriers, where L represents the spreading factor. This is accomplished by multiplying every symbol of the block for user k, where k ∈ {0,1,..., L - 1}, by a spreading code , -MC-CDMA with SFBC
In the next subsections, we describe the architecture of an SFBC MIMO MC-CDMA transmitter, and define the basic terms related to the PAPR of the involved signals.
System model
In an MC-CDMA system, a block of M information symbols each active user are spread in the frequency domain into N = LM subcarriers, where L represents the spreading factor. This is accomplished by multiplying every symbol of the block for user k, where k ∈ {0,1,..., L - 1}, by a spreading code ,
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Size: 4096 |
Author: emman |
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Description: ra_snr_gui.m
作用：统计不同信噪比下，五种信号的峰值旁瓣比RA和低高频均值比RM，绘制结果，参考图3.11和3.12
DFCW_RA_SNR.m
作用：产生正交离散频率编码信号，并计算峰值旁瓣比RA和低高频均值比RM
LFM_RA_SNR.m
作用：产生线性调频信号，并计算峰值旁瓣比RA和低高频均值比RM
OFDMLFM_RA_SNR.m
作用：产生正交频分线性调频信号，并计算峰值旁瓣比RA和低高频均值比RM
PC_RA_SNR.m
作用：产生正交相位编码信号，并计算峰值旁瓣比RA和低高频均值比RM
SIN_RA_SNR.m
作用：产生单载频信号，并计算峰值旁瓣比RA和低高频均值比RM
输入参数：
vSNR：信噪比向量
输出结果：
RA:峰值旁瓣比向量RA，对应信噪比向量
RM:低高频均值比向量RM，对应信噪比向量
calculateRA.m:
作用：计算不同信噪比下峰值旁瓣比RA和低高频均值比RM，参考论文3.4.5节
输入参数:
sig：输入信号，可以是多行MIMO信号，运算中将合并为1行信号
vSNR：信噪比向量
输出结果：
RA:峰值旁瓣比向量RA，对应信噪比向量
RM:低高频均值比向量RM，对应信噪比向量
sig_dfcw.m
作用：产生正交离散频率编码信号
sig_ofdm.m
作用：产生正交频分线性调频信号
sig_pc.m
作用：产生正交相位编码信号
-ra_snr_gui.m action: Statistics different SNR peak sidelobes than five signal RA and low high frequency average ratio RM, rendering the results, referring to Figure 3.11 and 3.12 DFCW_RA_SNR.m effect: generating orthogonal discrete frequency encoded signal, and calculate the peak sidelobe ratio RA and low and high frequency average ratio RM LFM_RA_SNR.m effect: generating chirp signal and calculates the peak sidelobe ratio RA and low high frequency average ratio RM OFDMLFM_RA_SNR.m effect: generating an orthogonal frequency division chirp signal and calculates peak sidelobe ratio RA and low and high frequency average ratio RM PC_RA_SNR.m effect: generating quadrature phase encoded signals and calculate peak sidelobe ratio RA and the average low and high frequency effects than RM SIN_RA_SNR.m: to produce a single carrier frequency signal, and calculate peak sidelobe ratio RA and RM lower than the average high-frequency input parameters: vSNR: SNR vector output: RA: peak sidelobe ratio v
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Size: 6144 |
Author: 小怪兽 |
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Description: Abstract—Diagonal Bell Laboratories Layered Space-Time (DBLAST)
structure offers a low complexity solution to realize the
attractive capacity of Multiple-input and multiple-output (MIMO)
systems. In this paper, we apply D-BLAST in orthogonal frequency
division multiplexing (OFDM) systems and address the issue of
channel estimation. Different other MIMO-OFDM, where
symbols at all tones are always available for decision-directed
channel estimation, in D-BLAST OFDM, we update estimated
channel parameters each time a layer is detected with a least
square (LS) approach, using a pieced combination of received signals
at previous and current OFDM blocks. The initial estimate is
further refined by a robust estimator to exploit the time correlation
of channel parameters among OFDM blocks. Computer simulation
results show the performance improvement over block-wise
channel estimation. It is also shown that D-BLAST with proposed
channel estimation is robust to fast fading of channel parameters.-Abstract—Diagonal Bell Laboratories Layered Space-Time (DBLAST)
structure offers a low complexity solution to realize the
attractive capacity of Multiple-input and multiple-output (MIMO)
systems. In this paper, we apply D-BLAST in orthogonal frequency
division multiplexing (OFDM) systems and address the issue of
channel estimation. Different other MIMO-OFDM, where
symbols at all tones are always available for decision-directed
channel estimation, in D-BLAST OFDM, we update estimated
channel parameters each time a layer is detected with a least
square (LS) approach, using a pieced combination of received signals
at previous and current OFDM blocks. The initial estimate is
further refined by a robust estimator to exploit the time correlation
of channel parameters among OFDM blocks. Computer simulation
results show the performance improvement over block-wise
channel estimation. It is also shown that D-BLAST with proposed
channel estimation is robust to fast fading of channel parameters.
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Size: 80896 |
Author: werad |
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