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channel capacity of multiple-input multiple-output systems with transmit and receive correlation

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Journal of Systems Engineering and Electronics 2008年第1期19卷 21-26页

作者： Wang Jun Zhu Shihua Wang Lei Liu Fang School of Electronics and Information Engineering Xi'an Jiaotong Univ. Xi'an 710049 P. R. China Beijing Communications Laboratories Co. Ltd. Advanced Wireless System Lab Beijing 100080 P. R. China

In order to investigate the impact of channel model parameters on the channel capacity of a multipleinput multiple-output （MIMO） system, a novel method is proposed to explore the channel capacity under Rayleigh fiat fading with correlated transmit and receive antennas. The optimal transmitting direction which can achieve maximum channel capacity is derived using random matrices theory. In addition, the closed-form expression for the channel capacity of MIMO systems is given by utilizing the properties of Wishart distribution when SNR is high. Computer simulation results show that the channel capacity is maximized when the antenna spacing increases to a certain point, and furthermore, the larger the scattering angle is, the more quickly the channel capacity converges to its maximum. At high SNR （〉12 dB）, the estimation of capacity is close to its true wlue. And, when the same array configuration is adopted both at the transmitter and the receiver, the UCA yields higher channel capacity than ULA.

关键词： multiple input multiple output channel capacity spatial correlation channel state information

channel capacity investigation of a linear massive MIMO system using spherical wave model in LOS scenarios

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Science China(Information Sciences) 2016年第2期59卷 45-59页

作者： Liu LIU David W.MATOLAK Cheng TAO Yongzhi LI Bo AI Houjin CHEN Institute of Broadband Wireless Mobile Communications Beijing Jiaotong University Department of Electrical Engineering University of South Carolina National Mobile Communications Research Laboratory Southeast University

Massive multiple-input multiple-output(MIMO) is a key technology for the 5th generation(5G)of wireless communication systems. The traditional plane wave channel model(PWM) is often not suitable for the large antenna structure, and in certain cases should be replaced by the more accurate spherical wave model(SWM). By using the spherical wave characterization method, this paper investigates the channel capacity performance of a linear massive MIMO system in line-of-sight(LOS) scenarios. Two types of access settings, the point to point(PTP) system and multi-user(MU) system, are considered. In the PTP setting, a geometrical optimization is performed to obtain configurations that are able to generate a full rank channel matrix for a linear massive MIMO system, which yields full spatial diversity even in LOS scenarios. Compared with the approximate and commonly applied rank-1 PWM, this is very useful for fixed wireless access and radio relay systems requiring high throughput. For the MU case, we compare the eigenvalue distributions of the LOS channels using the plane wave and spherical wave characterization method, and sum rate results are obtained by Monte Carlo simulations. The results show that MU systems using the more realistic and accurate SWM can achieve a higher sum rate than results from the PWM. This is beneficial and informative when designing massive MIMO wireless networks.

关键词： massive MIMO channel model plane wave model spherical wave model channel capacity

channel capacity Estimation in TDMS-Based MIMO Measurements

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Tsinghua Science and Technology 2011年第4期16卷 371-376页

作者：姚元郑剑锋冯正和 Tsinghua National Laboratory for Information Science and Technology Department of Electronic Engineering Tsinghua University

Time-division multiplexed switching （TDMS）-based multiple-input multiple-output （MIMO） channel sounders are widely used for wireless channel measurements due to their effective costs. However, meas- urement noise such as phase noise in the local oscillators as well as additive white Gaussian noise （AWGN） can result in significant errors in channel capacity estimates. This study analyzes the impact of phase noise and AWGN on channel capacity in TDMS-based MIMO measurements, with a channel capacity estimator presented that reduces the impact of noise on both the spatial multiplexing gain and on the power gain. Simulations demonstrate that the estimator consistently obtains the true capacity for various MIMO channel scenarios, even if only a limited number of observations are available.

关键词： channel capacity multiple-input multiple-output (MIMO) systems phase noise spatial multiplex-ing gain power gain

Statistical-mechanical analysis of multiuser channel capacity with imperfect channel state information

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Chinese Physics B 2008年第12期17卷 4451-4457页

作者：汪辉松曾贵华 The State Key Laboratory on Fiber-Optical Local Area Networks and Advanced Optical Communication Systems Electronic Engineering Department Shanghai Jiaotong University

In this paper, the effect of imperfect channel state information at the receiver, which is caused by noise and other interference, on the multi-access channel capacity is analysed through a statistical-mechanical approach. Replica analyses focus on analytically studying how the minimum mean square error （MMSE） channel estimation error appears in a multiuser channel capacity formula. And the relevant mathematical expressions are derived. At the same time, numerical simulation results are demonstrated to validate the Replica analyses. The simulation results show how the system parameters, such as channel estimation error, system load and signal-to-noise ratio, affect the channel capacity.

关键词： statistical mechanics channel capacity minimum mean square error channel estimation code division multiple access (CDMA)

Performance analysis on channel capacity in cooperative MIMO system

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Journal of Harbin Institute of Technology(New Series) 2012年第3期19卷 61-67页

作者：阮中迅孟维晓王宏宇李卓霖 School of Electronics and Information Engineering Harbin Institute of Technology

Recent years, cooperative technology has taken a lot of attention since it can improve the bit error rate （BER） and lower the transmit power in radio mobile networks, especially when the direct channel between the source and the destination is poor. Cooperative multiple input multiple output （Co-lVlIMO） is a kind of MI- MO technique, where the multiple inputs and outputs are formed via cooperation. The capacity of Co-MIMO system over wireless channel has been investigated a lot, however few papers pay attention to the locations of the channel that may affect the probability distributions of the variable and the effect of antenna spatial correlation. The results can be achieved by choosing sub-channels that is not related to other sub-channels. This paper focu- ses on this problem. The simulation results show that once we search the partner we should consider trade offs cooperation get optimum system performance. It further investigates that cooperation between different terminals can reduce antenna spatial correlation, thereby increase the capacity and throughput of the system, and even reach the ideal capacity of MIMO system.

关键词： cooperative MIMO channel capacity muhiple-antenna terminals

Range Extension and channel capacity Increase in Impulse-Radio Ultra-Wideband Communications

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Tsinghua Science and Technology 2010年第2期15卷 169-173页

作者： Roberto Rodes Antonio Caballero Jesper Bevensee Jensen Timothy Braidwood Gibbon Neil Guerrero Gonzalez Idelfonso Tafur Monroy DTU Fotonik Department of Photonics Engineering Technical University of Denmark

We theoretically analyze the channel capacity of a 5th-order Gaussian pulse-based ultra-wideband （UWB） system and experimentally demonstrate 2 Gbit/s UWB-over-fiber transmission systems incorporating wireless transmission. Both electrical and photonic UWB pulse generation methods are employed and its performance is compared. By utilizing optimum UWB pulse design and employing a digital signal processing （DSP） receiver, a bit-error-rate above the forward error correction （FEC） limit for 8 meters of wireless＇emis- sion is obtained in our photonic generation UWB system. A noticeable increase in the channel capacity is achieved compared to previously reported results.

关键词： impulse radio ultra-wideband UWB-over-fiber channel capacity personal area networks

Impact of channel estimation error on channel capacity of multiple input multiple output system

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Journal of Pharmaceutical Analysis 2007年第2期19卷 131-134,148页

作者：王君朱世华王磊 School of Electronics and Information Engineering Xi'an Jiaotong University

In order to investigate the impact of channel estimation error on channel capacity of multiple input multiple output (MIMO) system, a novel method is proposed to explore the channel capacity in correlated Rayleigh fading environment. A system model is constructed based on the channel estimation error at receiver side. Using the properties of Wishart distribution, the lower bound of the channel capacity is derived when the MIMO channel is of full rank. Then a method is proposed to select the optimum set of transmit antennas based on the lower bound of the mean channel capacity. The novel method can be easily implemented with low computational complexity. The simulation results show that the channel capacity of MIMO system is sensitive to channel estimation error, and is maximized when the signal-to-noise ratio increases to a certain point. Proper selection of transmit antennas can increase the channel capacity of MIMO system by about 1 bit/s in a flat fading environment with deficient rank of channel matrix.

关键词： Multiple Input Multiple Output channel capacity spatial correlation antenna selection

A Typical Cooperative MIMO Scheme in Wireless Ad Hoc Networks and Its channel capacity

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A Typical Cooperative MIMO Scheme in Wireless Ad Hoc Network...

A Correlation-Based Stochastic Model for Massive MIMO channel

2008 IEEE International Conference on Communications(ICC 2008)

作者： Haitao Zhao Yong Xi Jibo Wei School of Electronic Science and Engineering National University of Defense Technology Changsha China Jun Li Department of Customer Service Yiyang Branch of China Unicom Yiyang China

In this paper we proposed a typical cooperative MIMO system grounded on wireless mobile ad hoc networks and brought forward the problem of time efficiency in cooperative MIMO *** then adopting time efficiency,we analyzed the Shannon capacity limit of the cooperative MIMO *** analysis shows two ***,only when intra-cluster channel is better enough than inter-cluster channel,cooperative MIMO can bring increment of channel capacity;second,there should be an optimal number of cooperative partners in a cooperative MIMO *** instance it’s optimal to use 3 cooperative partners in the proposed typical cooperative MIMO system,when it can achieve a channel capacity increment of about 2bps/hz compared with direct transmission.

关键词： Wireless communication Cooperative MIMO channel capacity Wireless ad hoc networks

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China Communications 2024年第1期21卷 175-187页

作者： Yang Liu Gang Li Chengxiang Wang National Mobile Communications Research Laboratory School of Information Science and EngineeringSoutheast UniversityNanjing 211189China School of Internet of Things Engineering Jiangnan UniversityWuxi 214122China Pervasive Communication Research Center Purple Mountain LaboratoriesNanjing 211111China

In this paper,the channel impulse response matrix(CIRM)can be expressed as a sum of couplings between the steering vectors at the base station(BS)and the eigenbases at the mobile station(MS).Nakagami distribution was used to describe the fading of the coupling between the steering vectors and the *** measurements were carried out to evaluate the performance of this proposed ***,the physical implications of this model were illustrated and the capacities are *** addition,the azimuthal power spectrum(APS)of several models was ***,the channel hardening effect was simulated and *** showed that the proposed model provides a better fit to the measured results than the other CBSM,i.e.,Weichselberger ***,the proposed model can provide better tradeoff between accuracy and complexity in channel *** CIRM model can be used for massive MIMO design in the future communication system design.

关键词： CBSM channel capacity channel hardening channel modeling massive MIMO