Wireless Networks

Pishvaei, Seyed Mahmoud; Mozaffari Tazehkand, Behzad

doi: 10.1007/s11276-022-02936-8pmid: N/A

Due to the necessity of working under high mobility conditions in the next generation of mobile network communications, employing a practical multicarrier technique like Orthogonal Time Frequency Space (OTFS) is quite beneficial. OTFS could be perceived as a pre- and post-processing steps for the Orthogonal Frequency-Division Multiplexing (OFDM)-based techniques such as OFDM and Filter Bank Multi-Carrier (FBMC). Therefore, to achieve a better performance, we extended the FBMC by practicing the OTFS and designed the FBMC-based OTFS technique which benefits from both OTFS and FBMC characteristics. Also, to obtain massive connectivity and larger spectral efficiency, Non-orthogonal multiple access (NOMA) can be united with millimeter-Wave (mmWave) communication where the mmWave channel includes both line-of-sight (LOS) and non-line-of-sight (NLOS) path components. Based on the distance between the base station (BS) and users, novel pairing schemes are introduced which are composed of 3 capital words where the first, second and third words show the position of the near, mid-cell and far users to BS, respectively. The novel schemes are, (1) random near, random mid-cell and random far users (RRR), (2) nearest near, nearest mid-cell and nearest far users (NNN), and (3) nearest near, farthest mid-cell and farthest far users (NFF). To supply better performance in proposed schemes, massive number of antennas are considered for BS while each user has a single antenna. Concluded simulation results in the error and outage probability (OP) terms could certificate our system superiority over similar works.

Hoang, Tran Manh; Thang, Nguyen Nhu; Nguyen, Ba Cao; Tran, Phuong T.

doi: 10.1007/s11276-022-02947-5pmid: N/A

Recently, non-orthogonal multiple access (NOMA) and energy harvesting (EH) from radio frequency (RF) have been considered as promising candidates for next-generation mobile communications. In this paper, we investigate a novel solution to enhance the reliability and the supply stability of a downlink NOMA relaying networks, in which we integrate two techniques: (i) simultaneous wireless information and power transfer, i.e. the relay node can harvest the energy from source signals and use this energy to help forward information from source node to two user nodes; and (ii) data buffer aid at relay node, i.e. the data packets received from the source can be stored in a buffer and then be re-transmitted to the destination nodes only when the channel condition is good. The performance of the proposed system is analyzed rigorously to derive the system outage probability (OP), throughput and the average packet delay. Furthermore, a power allocation optimization problem to minimize the OP is formulated and solution to this problem is also provided. In addition, the optimal transmission rates to maximize the throughput of each user are presented in numerical results. Monte Carlo simulations are conducted to verify the analytical results, which confirms that with data buffer at relay, the overall outage probability (OOP) can be reduced significantly.

Li, Jianpo; Xue, Peng; Wang, Wenting

doi: 10.1007/s11276-022-02942-wpmid: N/A

Massive multiple-input multiple-output (MIMO) technology obtains better transmission efficiency because of the number of antennas at transmitting end and receiving end increased up to a few hundred, but it will also limit the performance due to pilot contamination arise from interference among users. In order to get the pilot contamination problem in massive MIMO systems settled, an Ant Colony Optimization Pilot Assignment strategy is proposed. Firstly, it uses the interference path diagram among users according to the user's channel transmission characteristics. Secondly, it performs optimization iterations according to the idea of the ant colony optimization algorithm to find the optimum route with the least total interference among users. Furthermore, it performs pilot assignment to users according to the required path to obtain a pilot assignment scheme with the least interference among users. The simulation results prove that the proposed method can suppress the pilot contamination problem and improve the performance of communication system with advantage.

Tuan, Pham Viet; Son, Pham Ngoc

doi: 10.1007/s11276-022-02938-6pmid: N/A

This paper studies the simultaneous wireless information and power transfer multi-antenna network with heterogeneous users and intelligent reflecting surface (IRS). Information decoding (ID) users, energy harvesting (EH) users, and power-splitting (PS) hybrid users require data and energy at the same time from the base station (BS) in the assistance of IRS. In the system model, the IRS reflects the incoming signal at each element by collaboratively adjusting phase shift to enhance the received signal at the users. In addition, the PS users exploit the PS circuit structure to simultaneously decode information and harvest energy via PS ratios. The target is to maximize the total PS-EH harvested power at PS and EH users with the non-linear EH model and limitation of BS transmit power while satisfying the signal-to-interference-plus-noise ratio requirements at ID and PS users. The information vectors at the BS, phase-shift vector at the IRS, and PS ratios at the hybrid users are jointly optimized by alternating optimization, semidefinite relaxation, sequential parametric convex approximation, and Gaussian randomization methods in the challenging non-convex problem. The numerical experiments present the convergence and effectiveness of the proposed algorithm. For certain parameters, the proposed IRS-assisted method enhances 17.65% total harvested power than the No-IRS one.

Liu, Yangyang; Zhang, Pinchang; Liu, Jun; Shen, Yulong; Jiang, Xiaohong

doi: 10.1007/s11276-022-02916-ypmid: N/A

By exploiting the carrier frequency offset (CFO) between a transmitter-receiver pair, this paper proposes a CFO-based physical layer authentication scheme for dynamic multiple-input-multiple-output (MIMO) systems. We first provide analytical modeling of dynamic CFO in such MIMO systems by jointly taking into account the intrinsic oscillator mismatch and Doppler frequency shift caused by node mobility, and employ the self-correlating and extended Kalman filtering techniques for the CFO estimation and prediction. By quantizing the difference between the estimated CFO and predicted one, we then apply the statistical signal processing techniques to develop a CFO-based physical layer authentication scheme for transmitter identity verification. With the help of tools from stochastic process and hypothesis testing theories, we further derive the analytical expressions for false alarm rate as well as detection rate to evaluate the performance of the proposed scheme. Finally, we provide extensive numerical results to demonstrate the efficiency of the proposed scheme.

Chauhan, Puspraj Singh; Kumar, Sandeep; Upaddhyay, Vipin Kumar; Soni, Sanjay Kumar; Mishra, Rajan; Kumar, Brijesh

doi: 10.1007/s11276-022-02922-0pmid: N/A

In this work, the asymptotic performance analysis over double shadowed κ\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\kappa $$\end{document}-μ\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\mu $$\end{document} fading channel is presented. More specifically, the unified asymptotic tight performance bounds for maximum ratio combining , selection combining and equal gain combining diversity receptions is presented. The system performance in terms of the outage probability (OP), symbol error probability (SEP) (coherent/non-coherent), the average probability of detection, and the average area under the receiver operating characteristic curve (AUC) is studied. To gain more insights and to validate the asymptotic slope of the results, the coding gain and diversity gain for OP, SEP, probability of missed detection, and complementary AUC for all the diversity techniques are also presented. It is found that the asymptotic slope of all the performance parameters and diversity techniques depend only on the number of multipath clusters and the diversity order of the system. Further, simulation results are presented to demonstrate the effectiveness of the proposed methodology under various channel conditions in diverse field of applications, such as vehicle-to-vehicle communication, wearable communication, and wireless power transfer related technologies .

Li, Guang-Hui; Yue, Dian-Wu; Qi, Feng

doi: 10.1007/s11276-022-02961-7pmid: N/A

As more challenging demands and potential applications increase in the sixth generation (6G) wireless networks, the future of mobile communications is exciting. Recently proposed intelligent reflecting surface (IRS) is a promising technology for improving the communication performance and building a programmable wireless propagation environment. However, high-precision configuration or perfect phase estimation of the IRS is unfeasible. In this paper, we study the IRS-aided millimeter wave (mmWave) multi-user multi-input multi-output (MIMO) systems with phase errors. Our objective is to maximize the achievable sum rate by joint optimizing the finited-resolution passive beamforming at the IRS, combiner, precoder, and power allocation. We first propose an iteratively sequential update (ISU) algorithm which can significantly reduce the complexity compared with the traditional exhaustive search algorithm (ESA) and cross-entropy (CE) method. Then we propose to use the genetic algorithm (GA) to further enhance the performance. The proposed algorithms can meet the requirements of low complexity and high performance respectively. Simulation results show that the IRS-aided systems can improve communication performance and coverage significantly compared with the conventional system. In addition, we observe that the system performance will not increase continuously with the number of the IRS elements when the total area of the IRS is fixed.

Malekpoor, Hossein; Abolmasoumi, Ali

doi: 10.1007/s11276-022-02950-wpmid: N/A

A low-profile 16-element printed dipole antenna (PDA) array supported by broadband Giuseppe Peano artificial magnetic conductor (AMC) is introduced for wireless communication systems. Firstly, a suggested PDA with a pair of the microstrip dipoles excited by an T-shaped microstrip feedline is used to expand the bandwidth in the measured range of 5.35–6.7 GHz (S11 ≤  − 10 dB). Then, the suggested second iteration Giuseppe Peano AMC reflector is inserted into the PDA to gain improved radiation efficiency. The realized result for the PDA with the 3 × 3 Giuseppe Peano AMC array with second iteration exhibits − 10 dB measured bandwidth from 4.50 to 7.20 GHz (more than 46%) for WLAN/ WiMAX and 5G applications. The suggested PDA with AMC compared to the PDA without AMC exhibits a size reduction of 35%, enhanced gain up to 8 dBi, and excellent impedance matching (at least − 18 dB) with uni-directional radiation patterns. By loading a 12 × 12 AMC reflector into the sixteen-element array of PDA, a low profile wideband structure with enhanced radiation properties is achieved. The measured S-parameters show the broad bandwidth from 4.46 to 7.02 GHz in C-band with enhanced gains of all elements and the suitable isolation of more than 28.5 dB for multiple-input multiple-output (MIMO) systems. Besides, the novel AMC unit cell is realized based on the recognized method as second iteration Giuseppe Peano fractal patch to operate at 6.10 GHz with an AMC bandwidth of 5.15–7.10 GHz (32%).

Senthil Kumaran, R.; Nagarajan, G.

doi: 10.1007/s11276-022-02960-8pmid: N/A

Wireless sensor network is a group of nodes combined with tiny sensors equipped with transceiver parts used for sensing, monitoring, and data collecting in various environments. It is not possible to support the battery support to the sensors while placed in an unmanned area. Hence, the sensor's energy should be vital, and it is very crucial. Combining the techniques of clustering and proper routing is one of the efficient schemes to save the energy of the sensor nodes. During the clustering process, cluster heads can be chosen with utmost care for load balancing. Along with cluster head selection, this proposed work also focussed on two major things. First, the appropriate relay node can be selected using the fuzzy inference system with sensor energy level as one input and the distance between the relay node and the cluster head node as another input. Secondly, the mobile sink collects the aggregated data from the relay node and sends it to the base station. On combining these two schemes, mobile sink and fuzzy based relay node routing Protocol is proposed. Simulation result shows that the proposed protocol has an improved number of alive nodes and a better network lifetime in terms of energy consumption compared with the existing schemes.

Ahmed, Bazil Taha; Rodríguez, Iván Fernández

doi: 10.1007/s11276-022-02951-9pmid: N/A

In this work, two elements (with two versions) compat UWB MIMO antennas are designed and fabaricted. CST software is used in the simulation process. The two elements MIMO antenna have a size of 29.5 × 60 mm2. Measured S parameters show that the MIMO antennas work well from 3 GHz up to 20 GHz (representing the maximum working frequency of the measurent instrumnts). Mesurement results show that the isolation between the antenna elemnts is higher than 23 dB for the first version of the two elements UWB MIMO antenna. In addition, mesurement results show that the isolation between the antenna elemnts is higher than 30 dB for the second version of the two elements UWB MIMO antenna. Measurements show a channel capacity loss lower than 0.4 bps/Hz and a low group delay variation.