scholarly journals Performance Analysis of Large Intelligent Reflecting Surface Aided Moderate MIMO for 5G Communication

2021 ◽  
Author(s):  
Fitsum Dessalegn Mekonnen ◽  
Muluneh Mekonnen Tulu ◽  
Sultan Feisso
Keyword(s):  
Energy Efficiency ◽  
Multiple Input Multiple Output ◽  
Cost Effective ◽  
Access Point ◽  
Wireless Channel ◽  
Transmit Power ◽  
Alternating Direction ◽  
Input Multiple Output ◽  
Reflecting Surfaces ◽  
Reflecting Surface

Abstract The recently completed 5G framework is the outcome of a few advanced technologies. Massive Multiple Input Multiple Output (MIMO), millimeter wave communication, and network densification are examples of these technologies. However, there are two disadvantages to this technology.1) the lack of control over the wireless channel, and 2) the wireless interface’s excessive power consumption. The concept of re-configurable Intelligent Reflecting Surfaces has emerged to answer the need for green and cost-effective future cellular networks. In this study, we’ll look at how using an Intelligent Reflecting Surface (IRS) improve the performance of moderate MIMO communication in terms of the rate, SINR, Energy efficiency and transmit power metrics. Despite the fact that the underlying issue is non-convexity, we use Lagrangian dual transform and Quadratic Transform to change and rearrange the original issue. After that, active and passive beam forming improved alternatively using an alternating Direction method of multiplier algorithm (ADMM.The IRS-aided system with a reasonable number of antennas at the access point (AP) outperforms the massive MIMO without IRS in terms of sum rate, SINR, Energy efficiency and transmit power metrics.

scholarly journals Power Optimization for Aerial Intelligent Reflecting Surface-Aided Cell-Free Massive MIMO-Based Wireless Sensor Network

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Tao Zhou ◽  
Kui Xu ◽  
Chunguo Li ◽  
Zhexian Shen
Keyword(s):  
Wireless Sensor Network ◽  
Sensor Network ◽  
Multiple Input Multiple Output ◽  
Tall Buildings ◽  
Wireless Sensor ◽  
Multiple Input ◽  
Input Multiple Output ◽  
Iterative Optimization Algorithm ◽  
Reflecting Surfaces ◽  
Reflecting Surface

Intelligent reflecting surfaces (IRSs) have significant advantages in enhancing the coverage and reducing the deployment cost of wireless networks. This paper studies an aerial IRS- (AIRS-) enhanced cell-free massive multiple-input multiple-output- (MIMO-) based wireless sensor network (WSN) in which multiple access points (APs) serve several sensor users (SUs). Direct links between the APs and SUs are blocked due to occlusion by tall buildings. Hence, we deploy an AIRS to improve the communication quality of the SUs. Our goal is to minimize the total transmit power of all APs under a given minimum signal-to-interference-plus-noise ratio (SINR) requirement. We propose a joint iterative optimization algorithm by designing an active beamforming mechanism at each AP and a passive beamforming mechanism at the AIRS to solve this problem. Simulation results illustrate the good performance of the proposed method.

scholarly journals Location-Aided Uplink Transmission for User-Centric Cell-Free Massive MIMO Systems: A Fairness Priority Perspective

2022 ◽  
Author(s):  
Chen Wei ◽  
Kui Xu ◽  
Zhexian Shen ◽  
Xiaochen Xia ◽  
Wei Xie ◽  
...  
Keyword(s):  
Large Scale ◽  
Mean Squared Error ◽  
Mimo Systems ◽  
Multiple Input Multiple Output ◽  
Access Point ◽  
Estimation Accuracy ◽  
Minimum Mean Squared Error ◽  
Input Multiple Output ◽  
User Centric ◽  
Assignment Scheme

Abstract In this paper, we investigate the uplink transmission for user-centric cell-free massive multiple-input multiple-output (MIMO) systems. The largest-large-scale-fading-based access point (AP) selection method is adopted to achieve a user-centric operation. Under this user-centric framework, we propose a novel inter-cluster interference-based (IC-IB) pilot assignment scheme to alleviate pilot contamination. Considering the local characteristics of channel estimates and statistics, we propose a location-aided distributed uplink combining scheme based on a novel proposed metric representing inter-user interference to balance the relationship among the spectral efficiency (SE), user equipment (UE) fairness and complexity, in which the normalized local partial minimum mean-squared error (LP-MMSE) combining is adopted for some APs, while the normalized maximum ratio (MR) combining is adopted for the remaining APs. A new closed-form SE expression using the normalized MR combining is derived and a novel metric to indicate the UE fairness is also proposed. Moreover, the max-min fairness (MMF) power control algorithm is utilized to further ensure uniformly good service to the UEs. Simulation results demonstrate that the channel estimation accuracy of our proposed IC-IB pilot assignment scheme outperforms that of the conventional pilot assignment schemes. Furthermore, although the proposed location-aided uplink combining scheme is not always the best in terms of the per-UE SE, it can provide the more fairness among UEs and can achieve a good trade-off between the average SE and computational complexity.

scholarly journals Virtual MIMO Beamforming and Device Pairing Enabled by Device-to-Device Communications for Multidevice Networks

2017 ◽  
Vol 2017 ◽  
pp. 1-10
Author(s):  
Yeonjin Jeong ◽  
Jooheum Yoon ◽  
Sang Hyun Lee ◽  
Yun Hee Kim
Keyword(s):  
Multiple Input Multiple Output ◽  
Access Point ◽  
D2d Communications ◽  
Channel State ◽  
Multiple Input ◽  
Device To Device ◽  
Input Multiple Output ◽  
Sum Rate ◽  
Device Pairing ◽  
The Internet Of Things

We consider a multidevice network with asymmetric antenna configurations which supports not only communications between an access point and devices but also device-to-device (D2D) communications for the Internet of things. For the network, we propose the transmit and receive beamforming with the channel state information (CSI) for virtual multiple-input multiple-output (MIMO) enabled by D2D receive cooperation. We analyze the sum rate achieved by a device pair in the proposed method and identify the strategies to improve the sum rate of the device pair. We next present a distributed algorithm and its equivalent algorithm for device pairing to maximize the throughput of the multidevice network. Simulation results confirm the advantages of the transmit CSI and D2D cooperation as well as the validity of the distributive algorithm.

scholarly journals MIMO SAR FORMATIONS: ORBITAL DIAMETER AND SYNCHRONIZATION TOLERANCES

2020 ◽  
Vol XLIII-B1-2020 ◽  
pp. 631-635
Author(s):  
A. Monti Guarnieri ◽  
D. Giudici ◽  
P. Guccione ◽  
M. Manzoni ◽  
F. Rocca
Keyword(s):  
Pulse Repetition Frequency ◽  
Multiple Input Multiple Output ◽  
Cost Effective ◽  
Power Resources ◽  
Multiple Input ◽  
Input Multiple Output ◽  
Single Input ◽  
Small Antenna ◽  
Along Track ◽  
The Impact

Abstract. Multiple-Input-Multiple Output (MIMO) Synthetic Aperture Radar (SAR) along-track formations can be used to fraction the power resources into compact, lightweight and cost-effective satellites, or to extend the swath coverage beyond the limit provided by a small antenna. In this second case, the Pulse Repetition Frequency (PRF) is kept low by implementing an inversion that solves up to N−1 ambiguities, given N observations. The simultaneous illumination – that allows for the N² gain due to the coherent combination of the N transmitters and the N receivers, is analyzed and shown not to be critical, as the more than N=2 sensors are assumed. Performance is evaluated for the N=2 and N=3 cases and compared with the Single Input Multiple Output formations, where one sensor is transmitting, and all are receiving. Finally, the impact of the across-track deviation from the orbit is modeled and evaluated.

scholarly journals What Role Do Intelligent Reflecting Surfaces Play in Non-Orthogonal Multiple Access?

2020 ◽  
Author(s):  
Arthur Sousa de Sena ◽  
Pedro Nardelli
Keyword(s):  
Communication Networks ◽  
Massive Mimo ◽  
Multiple Access ◽  
Multiple Input Multiple Output ◽  
Future Research ◽  
Data Rates ◽  
Input Multiple Output ◽  
Reflecting Surfaces ◽  
Key Techniques ◽  
Performance Gains

Massive multiple-input multiple-output (MIMO) and non-orthogonal multiple access (NOMA) are two key techniques for enabling massive connectivity in future wireless networks. A massive MIMO-NOMA system can deliver remarkable spectral improvements and reduced communication latency. Nevertheless, the uncontrollable stochastic behavior of the wireless channels can still degrade its performance. In this context, intelligent reflecting surface (IRS) has arisen as a promising technology for smartly overcoming the harmful effects of the wireless environment. The disruptive IRS concept of controlling the propagation channels via software can provide attractive performance gains to the communication networks, including higher data rates, improved user fairness, and, possibly, higher energy efficiency. In this article, in contrast to the existing literature, we demonstrate the main roles of IRSs in MIMO-NOMA systems. Specifically, we identify and perform a comprehensive discussion of the main performance gains that can be achieved in IRS-assisted massive MIMO-NOMA (IRS-NOMA) networks. We outline exciting futuristic use case scenarios for IRS-NOMA and expose the main related challenges and future research directions. Furthermore, throughout the article, we support our in-depth discussions with representative numerical results.

scholarly journals Performance Analysis and Comparison of Full Chip and Half Chip Rate DC and NC Code Acquisition in MIMO DSCDMA over Uncorrelated Rayleigh Wireless Channel

2011 ◽  
Vol 2011 ◽  
pp. 1-8
Author(s):  
N. Sathish Kumar ◽  
K. R. Shankar Kumar
Keyword(s):  
Performance Analysis ◽  
Spread Spectrum ◽  
Performance Metrics ◽  
Multiple Input Multiple Output ◽  
Direct Sequence Spread Spectrum ◽  
Wireless Channel ◽  
Acquisition Time ◽  
Code Acquisition ◽  
Nc Code ◽  
Input Multiple Output

This paper presents the performance analysis and comparison of full chip and half chip rate of noncoherent (NC) and differentially coherent (DC) code acquisition scheme in (multiple input-multiple output) MIMO assisted by direct sequence spread spectrum (DS-CDMA) wireless system when communicated over uncorrelated Rayleigh channel. Four schemes are investigated, namely, SISO with full chip rate, SISO with Half chip rate, MIMO with full chip rate, and MIMO with half chip rate by varying the code acquisition technique. The simulation is done in RF signal processing Lab using matlab tool box, and the performance metrics are considered, namely, Bit Error Rate (BER) and mean acquisition time (MAT). The simulation results indicate that DC performance is superior than NC in both full chip and half chip rate and also shown that half chip performance is better than full chip in both DC and NC code acquisition methods.

scholarly journals Adaptive Energy Efficiency Based Power Allocation for MIMO Radar Network

2019 ◽  
Vol 9 (1) ◽  
pp. 1720-1727
Keyword(s):  
Energy Efficiency ◽  
Power Consumption ◽  
Power Allocation ◽  
Target Detection ◽  
Communication Systems ◽  
Multiple Antennas ◽  
Multiple Input Multiple Output ◽  
Mimo Radar ◽  
Ratio Test ◽  
Input Multiple Output

Multiple-input multiple-output (MIMO) radar is used extensively due to its application of simultaneous transmission and reception of multiple signals through multiple antennas or channels. MIMO radar receives enormous attention in communication technologies due to its better target detection, higher resolution and improved accurate target parameter estimation. The MIMO radar has several antennas for transmitting the information and also the reflected signals from the target is received by the multiple antennas and it mainly used in military and civilian fields. But sometimes the performance of the MIMO radars is degraded due to its limited power. So the optimum power allocation is required in the communication systems of MIMO radar to improve its performance. In this paper, an Energy Efficiency based Power Allocation (EEPA) is used to allocate the power to a user of the clusters and also across the clusters. Here, the MIMO radars are clustered by using a naive bayes classifier. Subsequently, an efficient target detection is achieved by using Generalized Likelihood Ratio Test (GLRT) and then the clusters are divided into primary and distributive clusters based on the distance from the target. Here, the proposed methodology is named as EEPA-GLRT and the implementation of this MIMO radar system with an effective power allocation is done by Labview. The performance of the EEPA-GLRT methodology is analyzed in terms of the power consumption of various clusters. The performance of the EEPA-GLRT methodology is compared with Generalized Nash Game (GNG) method and it shows the power consumption of EEPA-GLRT is 0.0549 for cluster 1 of scenario 1, which is less when compared to the GNG method.

scholarly journals Energy Efficiency Optimization for Massive MIMO Non-Orthogonal Unicast and Multicast Transmission with Statistical CSI

Electronics ◽  
2019 ◽  
Vol 8 (8) ◽  
pp. 857 ◽  
Author(s):  
Wang ◽  
Huang ◽  
You ◽  
Xiong ◽  
Li ◽  
...  
Keyword(s):  
Energy Efficiency ◽  
Power Allocation ◽  
Mimo Systems ◽  
Multiple Input Multiple Output ◽  
Maximization Problem ◽  
Multicast Transmission ◽  
Deterministic Equivalent ◽  
Multiple Input ◽  
Input Multiple Output ◽  
Vector Valued

We study the energy efficiency (EE) optimization problem in non-orthogonal unicast and multicast transmission for massive multiple-input multiple-output (MIMO) systems with statistical channel state information of all receivers available at the transmitter. Firstly, we formulate the EE maximization problem. We reduce the number of variables to be solved and simplify this large-dimensional-matrix-valued problem into a real-vector-valued problem. Next, we lower the computational complexity significantly by replacing the objective with its deterministic equivalent to avoid the high-complex expectation operation. With guaranteed convergence, we propose an iterative algorithm on beam domain power allocation using the minorize maximize algorithm and Dinkelbach’s transform and derive the locally optimal power allocation strategy to achieve the optimal EE. Finally, we illustrate the significant EE performance gain of our EE maximization algorithm compared with the conventional approach through conducting numerical simulations.

scholarly journals Constructing Dynamic Multiple-Input Multiple-Output Logic Gates

2011 ◽  
Vol 2011 ◽  
pp. 1-12 ◽  
Author(s):  
Haipeng Peng ◽  
Gang Hu ◽  
Lixiang Li ◽  
Yixian Yang ◽  
Jinghua Xiao
Keyword(s):  
Noise Analysis ◽  
Multiple Input Multiple Output ◽  
Clock Cycle ◽  
Dynamic Logic ◽  
Logic Gates ◽  
Cost Effective ◽  
Research Direction ◽  
Threshold Method ◽  
Multiple Input ◽  
Input Multiple Output

Investigation of computing devices with dynamic architecture which makes devices have reconfigurable ability is an interesting research direction for designing the next generation of computer chip. In this paper, we present a window threshold method to construct such dynamic logic architecture. Here, dynamic multiple-input multiple-output (MIMO) logic gates are proposed, analyzed, and implemented. By using a curve-intersections-based graphic method, we illustrate the relationships among the threshold, the control parameter, and the functions of logic gates. A noise analysis on all the parameters is also given. The chips based on the proposed schemes can be transformed into different arrangements of logic gates within a single clock cycle. With these schemes in hand, it is conceivable to build more flexible, robust, cost effective, yet general-purpose computing devices.

scholarly journals Space-Time Trellis Coding with Equalization

2019 ◽  
Vol 4 (9) ◽  
pp. 207-211
Author(s):  
Ibukunoluwa Adetutu Adebanjo ◽  
Yekeen Olajide Olasoji ◽  
Micheal Olorunfunmi Kolawole
Keyword(s):  
Mean Squared Error ◽  
Mimo Systems ◽  
Multiple Input Multiple Output ◽  
Space Time ◽  
Wireless Channel ◽  
Cyclic Prefix ◽  
Single Carrier ◽  
Minimum Mean Squared Error ◽  
Mmse Receiver ◽  
Input Multiple Output

As we are entering the 5G era, high demand is made of wireless communication. Consistent effort has been ongoing in multiple-input multiple-output (MIMO) systems, which provide correlation on temporal and spatial domain, to meet the high throughput demand. To handle the characteristic nature of wireless channel effectively and improve the system performance, this paper considers the combination of diversity and equalization. Space-Time trellis code is combined with single-carrier modulation using two-choice equalization techniques, namely: minimum mean squared error (MMSE) equalizer and orthogonal triangular (QR) detection. MMSE gives an optimal balance between noise enhancement and net inter-symbol interference (ISI) in the transmitted signal. Use of these equalizers provides the platform of investigating the bit error rate (BER) and the pairwise error probability (PEP) at the receiver, as well as the effect of cyclic prefix reduction on the receivers. It was found that the MMSE receiver outperforms the QR receiver in terms of BER, while in terms of PEP; the QR receiver outperforms the MMSE receiver. When a cyclic prefix reduction test was carried out on both receivers, it yields a significant reduction in BER of both receivers but has no significant effect on the overall performance.

Sign in / Sign up

Export Citation Format

Share Document