International Journal of Wireless and Microwave Technologies @ijwmt
Статьи журнала - International Journal of Wireless and Microwave Technologies
Все статьи: 544
Статья научная
This paper explores the potential of Ultra-Massive Multiple Input Multiple Output (UM MIMO) systems as a key technology for 6G wireless communications within the Terahertz (THz) frequency band (0.1 – 10 THz). The THz spectrum offers immense capacity and speed advantages but presents significant challenges, such as higher propagation losses and limited coverage range due to atmospheric absorption and signals spreading. The study provides a comprehensive analysis of UM MIMO’s technical performance in overcoming these challenges, focusing on key metrics such as signal propagation, system capacity, and coverage range. Additionally, the research examines the optimization of beam dynamics and spectral efficiency in UM MIMO systems under various wireless channel conditions and precoding techniques. The findings highlight the importance of advanced antenna techniques and adaptive beam management in maximizing the efficiency and viability of 6G THz networks, positioning UM MIMO as a fundamental solution for next-generation wireless communication.
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Статья научная
OFDM is a technique that is chosen for high data rate communication and is important for 4th generation communication systems. To provide best possible quality of service, intelligent allocation of resources such as power, bandwidths are necessary. Various algorithms have been proposed for allocation of resources. Fuzzy Rule Based System (FRBS) and Particle Swarm Optimization (PSO) algorithm are used for optimization of code rate, modulation and power. FRBS is used to choose the best possible modulation and code rate and PSO is used for better power allocation.
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Статья научная
Researches in the reduction of peak-to-average power ratio (PAPR) from orthogonal frequency division multiplexing (OFDM) output signals are being done using many techniques. Selected mapping (SLM) technique is a distortion-less technique and is a well known method to reduce high PAPR of OFDM signal. One drawback of SLM is its requirement of side information bits to recover original data block at the receiver side which lead rate of data loss. In this paper, we have proposed a sequential phase sequence SLM (SPS-SLM) based OFDM transceiver without side information and studied its performance. For the proposed method, a specific set of phase sequences is designed. MATLAB simulation shows that the proposed scheme performs well in terms of PAPR. Proposed method provides almost the same PAPR reduction performance compared to the conventional SLM method requiring side information.
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PPLS: personnel presence locator system – an amalgam of RF ranging & Zigbee in WSN
Статья научная
In this day and age of occupied time plans, individuals are confronting numerous issues in following the employees and specialists in colleges, schools, universities, doctor's facilities and so forth, hence it ends up vital that each assignment is expert intelligently, productively and in an auspicious way. To achieve this, easy accessibility of people of interest is a must. To alleviate this problem, we propose a solution called “Personnel Presence Locator System (PPLS)” that is an internetworked amalgam of small systems working independently. Moreover, in this article, we give an overview of the naturally multidisciplinary writing of human-detection, concentrating essentially on the extraction of five regularly required properties: in particular Location, Count, Presence, Track, and Identity. The objective of this work is to uncover the abilities and constraints of existing solutions from different disciplines, to manage the production of new frameworks like PPLS and point toward future research bearings.
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PRDSA: Effective Parallel Digital Signature Algorithm for GPUs
Статья научная
RSA based Digital Signature algorithm is an electronic scheme to ensure the security, authenticity and integrity of an electronic document intended to be used on Internet. Due to the involvement of RSA in signing and signature verification which is based on the series of modular multiplications and modular reductions on very large integers, the RSA based digital signature algorithm become compute-intensive and takes lot of time and energy to execute. A potential solution to this problem is to use the massive parallel powers of the multiprocessors of GPU that can simplify its complex computational part via CUDA programming. This paper presents a faster GPU based pRDSA algorithm which serves the same purpose as the RSA Digital Signature Algorithm but with less computational complexity. Proposed algorithm is an energy efficient parallel version of Digital Signature Algorithm to achieve high performance in the area of network security. It is based on SIMD model of parallel programming and implements repeated square-and-multiply method to compute the digital signature. The conceptual model of pRDSA and its performance have been discussed in this paper.
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PRoPHET Using Optimal Path Hops
Статья научная
The opportunistic network paradigm has no stable path and synchronous end-to-end communication. In such an environment, the bundle originator or the infected node stores a redundant copy in its buffer. This copy is replicated to other encountered susceptible nodes based on routing decision. The performance of the employed routing is based on delivering the bundle through optimal paths. This paper improves the decision criteria of the PRoPHET routing. This enhancement is achieved by employing the bundle probability and the optimal path hops. We have called our proposed improved PRoPHET utilizing Optimal Path Hops (PRoPHET-OPH). The evaluating of its performance is conducted by delivery probability, mean delay and percentage of overhead. Numerical findings exhibit that the PRoPHET-OPH performance is superior compared with the traditional PRoPHET.
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Pattern-based and Time-Synchronised Passwords
Статья научная
World has been changed; every person is using a number of software, websites, and other systems that are using text-based passwords as a method of authentication. These passwords need to be strong, hard to guess, and need to be stored in a secure environment. Major problems with passwords are caused by human limitations to remember passwords for different accounts. A trade-off between password security and human-memorability made it difficult to create passwords that are strong enough and easy to remember. No satisfactory solutions have been offered to problems associated with a password such as shoulder surfing, eavesdropping, keylogging programs, Trojan horse, brute force attacks, etc. This study suggests a new easy to use approach for creating a password that is easy to remember even for a large number of accounts. Here in this paper, we proposed two methods one is pattern-based passwords, a simple method that is solving the problem of memorability, another is the idea of Time-Synchronized Passwords (TSP), a novel method for creating passwords that are dynamic in nature and change with the passage of time. The novality of TSP is that instead of storing the passwords in database the patterns are stored, and these patterns are related linked with time. The significance of storing pattern instead of actual password is that at a specific time, the password will have only one instance known to the creator of the password, and this particular instance will be different from instances at other times and thus avoids shoulder surfing, eavesdropping, keylogging, and other problems associated with passwords. These methods are easy to implement and can be used in any system.
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Performance Analysis between Analog OFDM & Digital OFDM System
Статья научная
Orthogonal Frequency Division Multiplexing (OFDM) signaling has been widely used for high data rate transmission applications due to its high spectral efficiency and robustness to the frequency selective fading channels. One of the major drawbacks of the analog OFDM system is frequency shifting in every sub-carrier. That's why bit error rate increased in analog OFDM system. In this research, we want to solve the problem of the analog OFDM system by using IFFT circuit instead of the local oscillator. The IFFT circuit takes an input as frequency domain and provides output as a time domain signal for 4-QAM modulation. Basically IFFT circuit acts as a local oscillator in the analog OFDM system. The IFFT circuit only executes operation on a discrete frequency domain signal which is converted into a time domain signal by its. So no frequency shifting occurs in every sub-carrier in the digital OFDM system. As a result BER also decrease in digital OFDM system over the analog OFDM system.
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Performance Analysis of Differential Evolution Algorithm based Beamforming for Smart Antenna Systems
Статья научная
This paper presents smart antenna array beamforming using differential evolution algorithm. The excitation values of the elements in the array are smartly adjusted to control side lobe levels and placing nulls in the interference signal direction while maintaining the beam in the desired signal direction. Different cases are considered to illustrate the performance of this technique. Simulation results show that this evolution algorithm is better than the traditional beamforming algorithms for Smart antenna systems.
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Performance Analysis of FBMC over OFDM for High Data Rate MIMO Configurations
Статья научная
The burgeoning demand of high data rate in next generation wireless communication, the antecedent of the evolution of new multicarrier modulation technique FBMC (Filter Bank Multicarrier) system is OFDM (Orthogonal Frequency Division Multiplexing). Although OFDM has numerous merits but it consumes higher bandwidth due to its cyclic prefix to eliminate ISI (Inter Symbol Interference) in fading channel and shows large PAPR (Peak to Average Power Ratio) in transmission system. To mitigate these problems, FBMC is more suitable candidate in high speed MIMO (multiple input multiple output) system. At first, in this paper, the responses of OFDM and FBMC system have been analyzed with AWGN and Rayleigh fading channel under theoretical and simulation environment. Besides this, Peak to Average Power Ratio (PAPR) with reduction technique, clipping is applied to know the behavior of these systems. Finally, in the area of MIMO scheme, each system is concatenated with MRC, Alamouti STBC and Generalized STBC to find FBMC as superior contender for 5G. Results show that using 16 QAM modulation, BER performance of FBMC significantly achieves 2dB compared to error rate of OFDM in theoretical and empirical analyses under AWGN and Rayleigh channel. Moreover, the clipping technique enhances the response of FBMC in terms of PAPR compared to OFDM approximately 0.5 dB. In MIMO configurations, MRC-FBMC exhibits the improved performance with 2 dB approximately over MRC-OFDM system. Results also show that in the case of Alamouti STBC, at 30dB and 35dB, FBMC (2×1) and (2×2) configurations achieve BER improvement 5×10-4, 3×10-4 respectively than OFDM (2×1) and (2×2) configurations. Generalized STBC investigation reveals that to reach FBMC BER performance, OFDM needs at least 2dB increment at specific error rate. In a nutshell, this paper brings up three distinct types of appealing features of FBMC such as good BER response, reduced PAPR, and suitability in MIMO configuration compared to OFDM. These distinct features make FBMC an ultimate choice in the emerging areas of MIMO networks.
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Performance Analysis of HWMP Protocol in Wireless Mesh Network
Статья научная
Wireless Mesh Networks (WMNs) play a vital role in next-generation wireless networking, with applications ranging from last-mile wireless internet, transportation systems enterprise, enterprise networks, home networking, and wireless community networks are all examples of wireless community networks.Individual vendors created several proprietary mesh systems, but IEEE organized the IEEE 802.11s task force to design a meshed networking exposition to assure interoperability.In this paper, we evaluate the Quality of service parameters such as throughput, delay, PDR and jitter of mesh protocol.We simulated the HWMP protocol's performance,the present work is an attempt to address the problem related to wireless mesh networks by minimizing the delay and maximizing the throughput of the network.
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Performance Analysis of IoT Cloud-based Platforms using Quality of Service Metrics
Статья научная
There are several IoT platforms providing a variety of services for different applications. Finding the optimal fit between application and platform is challenging since it is hard to evaluate the effects of minor platform changes. Several websites offer reviews based on user ratings to guide potential users in their selection. Unfortunately, review data are subjective and sometimes conflicting – indicating that they are not objective enough for a fair judgment. Scientific papers are known to be the reliable sources of authentic information based on evidence-based research. However, literature revealed that though a lot of work has been done on theoretical comparative analysis of IoT platforms based on their features, functions, architectures, security, communication protocols, analytics, scalability, etc., empirical studies based on measurable metrics such as response time, throughput, and technical efficiency, that objectively characterize user experience seem to be lacking. In an attempt to fill this gap, this study used web analytic tools to gather data on the performance of some selected IoT cloud platforms. Descriptive and inferential statistical models were used to analyze the gathered data to provide a technical ground for the performance evaluation of the selected IoT platforms. Results showed that the platforms performed differently in the key performance metrics (KPM) used. No platform emerged best in all the KPMs. Users' choice will therefore be based on metrics that are most relevant to their applications. It is believed that this work will provide companies and other users with quantitative evidence to corroborate social media data and thereby give a better insight into the performance of IoT platforms. It will also help vendors to improve on their quality of service (QoS).
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Статья научная
Millimeter-wave (mm-wave) communication stands as a vital technology for future wireless networks, necessitating efficient beamforming techniques to mitigate significant path loss and harness the extensive mm-wave spectrum. Traditional fully digital beamforming methods are often deemed unfeasible due to the substantial costs and energy requirements, which stem from the need for individual radio frequency (RF) chains for each antenna element particularly in Massive MIMO systems. Hybrid beamforming emerges as a more economical solution, reducing both hardware expenses and energy consumption by utilizing a limited number of RF chains. This paper offers an in-depth evaluation of hybrid beamforming in 5G and beyond mm-wave systems, proposing a new classification framework for various hardware configurations. The research employs a practical approach to compare different strategies, focusing on two main factors: the beam patterns produced with optimal and hybrid weights, and the resulting spectral efficiency, which is a key performance metric. The findings indicate that the beam patterns generated with both optimal and hybrid weights display comparable characteristics, especially for dominant beams. Additionally, the study shows that increasing the number of data streams leads to a significant boost in spectral efficiency, an essential element for enhancing 5G network performance. The systematic comparisons delve into the interactions and trade-offs between these design aspects, highlighting promising candidates for hybrid beamforming in the wireless communication systems of the future.
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Performance Comparison Of Beamforming And Multiplexing Techniques Using Smart Antenna Array
Статья научная
Meeting the demands that are expected from future wireless generation networks poses intriguing challenges for today's wireless system designers. The demand for higher data rate and better quality of service (QoS) in wireless communications continue to grow rapidly in current world global community. Obtaining these requirements becomes challenging for wireless communication systems due to the problems of channel fading, higher power and bandwidth limitations. One of the most promising solutions to this problem is the Multiple Input Multiple Output (MIMO) system. This paper compared the performance of spatial multiplexing MIMO scheme with beamforming at a data rate of 100Mb/s. The proposed wireless system was developed with smart antenna arrays at both the transmitter and receiver. The results obtained show that spatial multiplexing technique produced better spectral efficiency than beamforming. The BER performance of beamforming technique outperforms that of spatial multiplexing technique even when enhanced by V-BLAST algorithm under the same simulation environment. The proposed system outperforms the conventional MIMO.
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Статья научная
The fifth generation (5G) wireless technology has a significant impact on individuals' lives and work, and this impact is expected to increase in the future. The Orthogonal Frequency Division Multiplexing (OFDM) method, which is currently used in fourth generation (4G) technology, has limitations in meeting certain criteria such as data rates and speed for the latest technology due to issues such as sideband leakages, high Peak-to-Average Power Ratio (PAPR), and poor spectrum utilization. Additionally, the increasing demand for Internet of Things (IoT) and user-centric processing makes the OFDM method impractical. As a result, alternative technologies are being explored to meet these needs. Filter Bank Multicarrier (FBMC) and Universal Filtered Multicarrier (UFMC) are potential candidates for 5G technology. This paper focuses on the evolution of FBMC from OFDM, and then compares the performance of FBMC and UFMC by analyzing various modulation schemes such as Quadrature Amplitude Modulation (QAM), Phase Shift Keying (PSK), PAPR, and Bit Error Rate (BER) through Additive White Gaussian Noise (AWGN) and Rayleigh fading channels. A theoretical BER model is also established to validate the simulated BER results. In this paper BER is analyzed in terms mathematical and simulation based approaches. To validate this simulation based method, it can be compared with the theoretical BER results to verify the accuracy of this simulation. Result portays that, the theoretical results and the simulated results are quite close through the Additive White Gaussian Noise (AWGN) channel.
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Статья научная
In this paper, we have investigated the performance of IEEE 802.15.3a channel model with different modulation scheme. The performance parameter Average Bit Error Rate (ABER) is selected. We find out the BER performance of UWB system over the 802.15.3a indoor channel model for all channels profile CM1, CM2, CM3 and CM4 with different modulation scheme. In this paper, all modulation scheme used in UWB are included in different main categories. The major categories are synchronous and asynchronous. In synchronous mode, we again divided different modulation scheme e.g. BPSK, PPM, PAM etc into antipodal and orthogonal schemes. In the asynchronous category, we have studied about DPSK. All these modulation categories are comparing on the common platform and finally we got antipodal modulation scheme category is good for UWB in term of ABER.
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Performance Evaluation of Channel Codes for High Data Rate Mobile Wireless System
Статья научная
Mobile wireless system incorporates dual sphere in terms of mobility as well as computing. Such systems have revamped momentously resulting in expedient wireless devices. Current wireless communication requires enormous data rates, streaming audio/video, asymmetric access/multiple access, fully-integrated, low cost, reliable seamless systems with the capability of providing voice, high speed data, and video with minimum latency and long battery life to enhance error free communication. However, there are many obstacles and bottlenecks to achieving this in practice. These bottlenecks include limited spectrum, limited energy, multipath fading and propagation loss, cost, standardization processes. This paper focuses on coding and modulation techniques for wireless communications so as to reduce/overcome many of these obstacles. To put the discussion in perspective, a short background on the coding and modulation approaches of wireless communication systems is provided. The turbo coding is mainly chosen to facilitate the wireless communication. The paper enlightens the impetus behind using turbo codes for high data rate mobile wireless systems. Paper explains how better out-turns can be yielded when approaches like cyclic redundancy check and scrambling are embedded with coding. The BER performance and SNR ratio are observed for illustrating variance between convolution and turbo coding for different rates and modulations. Simulation results are plotted using Matlab software.
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Статья научная
Convergecast communication is used in many sensor applications .The flow of data in convergecast routing is from many to one i.e. many sensory nodes sense the data and send through parent child relation to the root node or sink node. Convergecast routing is always followed by broadcasting. In broadcast communication is from one to many and in convergecast it is from many to one. As sensor nodes have limited battery capacity main focus is to save energy. As compare to wired network wireless network is prone to attacks and it is less reliable than the wired network. This paper investigates the affect of header length of network layer on the BER, SNIR, backoff duration, SNR and latency of convergecast routing with the help of omnet++ simulator.
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Статья научная
The advancement of wireless communication technology is growing very fast. For next-generation communication systems (like 5G mobile services), wider bandwidth, high gain, and small-size antennas are very much needed. Moreover, it is expected that the next-generation mobile system will also support satellite technology. Therefore, this paper proposes a slotted star-shaped dual-band patch antenna that can be used for the integrated services of satellite communication and 5G mobile services whose overall dimension is 15×14×1.6 mm3. The proposed antenna operates from 18.764 GHz to 19.775 GHz for K-band satellite communication and 27.122 GHz to 29.283 GHz for 5G (mmWave) mobile services. The resonance frequencies of the proposed antenna are 19.28 GHz and 28.07 GHz having bandwidths of 1.011 GHz and 2.161 GHz, respectively. Moreover, the proposed dual-band patch antenna has a maximum radiation efficiency of 76.178% and a maximum gain of 7.596 dB.
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Статья научная
This paper presents a microstrip patch antenna incorporated with electromagnetic band gap (EBG) structure on substrate and defected ground structure (DGS) in the ground plane. Electromagnetic Band Gap materials are artificially engineered structures that improve the performance of the patch antennas. It is manifested that applications of both EBG and DGS outcomes in the remarkable improvement of return loss level from -20.2dB to -31.5dB and bandwidth from 155MHz to 202 MHz respectively. The most fascinating characteristic of the proposal is the capability of increasing the gain, directivity and the total efficiency of the antenna without affecting the other essential parameter like bandwidth which makes the designed antenna applicable for Radio Frequency portable devices operating at 6.1 GHz.
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