Broadband Wireless Technology Research Articles

Long Term Evolution Simulator - A Survey

Objectives: Long Term Evolution(LTE) can be defined as a 4G wireless broadband technology developed by the 3GPP. It becomes the hopeful broadband ubiquitous Internet access technology. Methods: To maximize its working and performance many research works are going on in this field.It requires a flexible, more realistic and standard simulation environment is required to check its performance. LTE simulator is of different kinds system-level simulator and linklevel simulator, hence there is a need to study in detail about this simulators. Findings: In this paper different simulators are discussed. The different simulators include physical-layer simulator, system-level simulator, link-level simulator. All simulator are analyzed with the BER (Bit Error Rate) and throughput results. Applications: This paper help to analyze the different types of simulators. Which helps to increase the performance of the LTE.

Blind key distribution mechanism to secure wireless metropolitan area network

IEEE 802.16, also known as WMAN is a promising broadband wireless technology that provides a great support for Next Generation Networks (NGN). Due to the continuous evolution of new technologies and increasing diverse set of mobile users, WMAN has huge security vulnerabilities. So, there is an intrinsic need to address WMAN security and reliability pitfalls. Therefore, we propose an enhanced version of Privacy Key Management Protocol Version 2 (e-PKMv2) based security scheme for secured data transmission between the Base Station (BS) and the Subscriber Station (SS) in WMAN. For this, we introduce a new technique called Blind Key Distribution (BKD) which increases the security of Authorization Key (AK) significantly in the key management protocol. We show how the proposed e-PKMv2 ensures secure key exchange in WMAN. Finally, the performance analysis of both the existing and proposed cryptosystem is provided.

Analysis of MIMO-OFDM using different Modulation Techniques

MIMO-OFDM system is fast growing new wireless broadband technology which has capability of high data rate transmission and advantages like inter carrier interference (ICI) reduction; high reliability; and better performance in multi-path fading. The major effect to be considered at receiver is fading effects which must be mitigated at receiver using equalization technique. In this paper we demonstrated the BER performance of the OFDM system with two different equalizers (ZF and MMSE). Proposed OFDM system is demonstrated using various modulation techniques that is BPSK, QPSK, 16-QAM and 64-QAM using multipath fading channels that is AWGN (Additive White Gaussian Noise) and Rayleigh channel.

An Analysis of VoIP Application in Fixed and Mobile WiMAX Networks

WiMAX is a wireless broadband technology, which promises maximum coverage area and high data rates. WiMAX provides last mile connectivity. This network defines two working models such as fixed WiMAX and mobile WiMAX. The main aim of this paper is to compare and also analyze the performance of the VoIP application over fixed and mobile WiMAX, with respect to various codecs such as G.711, G.723.1ar5.3, G.726ar24, G.728ar16 and G.729. We have considered few QoS parameters such as average end-to-end delay, throughput, average jitter, average one-way delay and average MOS. From the obtained result, codec G.711 and G.726ar24 performs better when compared to other codecs in both fixed and mobile WiMAX network.

The Effects of Consumer Characteristics on Information Searching Behavior in Wireless Mobile SNS: Using SEM Analysis

With a rapid development of the wireless broadband technology, consumers can have more freedom in searching and exchanging of information without the limitation of time and space. This article constructs a research framework of consumer characteristics on mobile social network and its influence on information searching behavior. This article aims to figure out the law of the consumers' information searching behavior on wireless mobile social internet, and applies some suggestions for enterprises to explore the mobile social internet marketing. With the collected data from 392 valid random samples that have been analyzed by structural equation model, the results of the empirical analysis shows that: consumer characteristics (including the sense of belonging, perceived risk, price sensitivity) have positive influence on information searching behavior of consumers, and the sense of belonging has positive influence on information searching behavior through customer participation.

Orthogonal frequency division multiple access downlink physical layer communication for IEEE 802.16‐2009 standard

Worldwide interoperability for microwave access (WiMAX) is a wireless broadband technology, which supports point to multi-point (PMP) broadband wireless access. WiMAX is basically a new shorthand term for IEEE Standard 802.16. This standard determines the air interface, including the medium access control layer and physical layer (PHY), of consolidated fixed and mobile point to-multipoint broadband wireless access frameworks offering numerous services. WiMAX PHY incorporates orthogonal frequency division multiplexing/orthogonal frequency division multiple access (OFDM/OFDMA) as the modulation technique in uplink as well as downlink. Hence, this study addresses OFDMA basics, OFDMA frame structure, OFDMA symbol, OFDMA PHY as per IEEE 802.16e-2009 standard. It also explains OFDMA time-division duplexing frame which consists of partial usage of subchannels and adaptive modulation and coding zones in the downlink from base station to two mobile stations (MS). The author analysed the system performance by reconfiguring different channels such as additive white Gaussian noise (AWGN), flat fading channel and multipath fading or frequency-selective channels. The impact of each channel on received signals (MS 1 and MS 2) is shown in figures and the corresponding values are noted in a table.

LTE-advanced pro: part 1 [Guest Editorial

Long Term Evolution (LTE) has become the most successful mobile wireless broadband technology, serving over one billion users as of the beginning of 2016. However, looking at the penetration rate, LTE serves only 14.5 percent of the current 7.3 billion mobile subscriptions. Consequently, there is still significant room for LTE to grow as a mobile technology; it will be serving users for a long time to come.

Interoperability Among Broadband Wireless Technologies in a Testbed Environment

As we move towards the next generation networks, one of the fundamental issues to consider is the integration of wireless technologies. Integrated networks will have impressive capabilities as well as cumbersome challenges in areas such as Radio Resource Management (RRM), Quality of Service (QoS), Security, Mobility, and Power Management. In this paper, we tackle one of the challenges facing researchers and developers in this area. The main objective of this research was to build an integrated WiFi–WiMAX network in a test-bed environment, and to investigate the effects of integration on the QoS performance. This study is based on practical deployment and measurements in a laboratory environment. We successfully implemented an integrated system and experimented with various QoS scenarios. A set of RRM schemes were defined for the integrated networks and actual results collected from network analyzer showed that the QoS requirements were met throughout the WiFi–WiMAX networks.

차세대 무선 브로드밴드 산업 동향과 활성화 방안

Ongoing advances in wireless broadband technologies can affect all of industrial society. As new wireless broadband technologies emerge, they will improve competition between established industries and their current services and produce new industries and new converged services. This paper analyzes the trend of next-generation wireless broadband and suggests ways of activating the industry further. To this end, we analyze the trend for previous wireless broadband industries and find out three influential factors (content, wireless network technology, and service) that will produce the continued growth of wireless broadband. Using these three factors, we propose a network technology-driven growth model. Based on that model, we offer activation plans for next-generation wireless broadband industries. This study thus provides an insightful perspective for next-generation wireless broadband industries by establishing additional useful guidelines for developing wireless broadband industries in the future.

Performance Analysis of Buffer Aware Scheduling for Video Services in LTE Network

Recent advancements in broadband wireless communication technologies enable mobile users to receive video streaming services with various smart devices. The long term evolution (LTE) network provides high bandwidth and low latency for several emerging mobile applications. This paper proposes the buffer aware scheduling (BAS) approach to schedule the downlink video traffic in LTE network. The proposed BAS scheme applies the weighting function to heuristically adjust the scheduling priority by considering the buffer status and channel condition of UE so as to reduce the time that UE stays in the connected state without receiving data. Both of 1080P and 2160P resolution video streaming sources were applied for exhaustive simulations to examine the performance of the proposed scheme by comparing to that of the fair bandwidth (FB) and the best channel quality indicator (CQI) schemes. The simulation results indicate that the proposed BAS scheme not only achieves better performance in power saving, streaming delivery time, and throughput than the FB scheme while maintaining the similar performance as the best CQI scheme in light traffic load. Specifically, the proposed scheme reduces streaming delivery time and generates less signaling overhead than the best CQI scheme when the traffic load is heavy.

Impact of Distinctive Jamming Signals on WiMAX System

In this recent era wireless communication industries have focused on the uses of broadband system having high quality functions. Because of this issue new advances with high transmission capability technologies are designed. The broadband wireless access turns into the best approach to satisfy the high business interest for expanding the web connection. WiMAX (Worldwide Interoperability for Microwave Access) is a broadband wireless technology is developed to meet the growing demand of increased data rate and accessing the internet at high speeds as well as low cost maintenance. It is based on the IEEE 802.16-2004 standard family. In this system allows using an efficient bandwidth in a wide frequency range, and last mile solution for broadband internet access. The jamming and scrambling are two important threats in WiMAX system. This paper presents the simulation of WiMAX system with and without impact of jamming signals. The performance parameter BER of the system is analyzed in all conditions and the result implies the enormously changes with the utilization of distinctive jamming signals. The aim of this paper is to analyze and simulate WIMAX OFDM system in the presence of interference signals. MATLAB Simulink software is used to simulate and analyze the WIMAX system. The simulation results include the performance analysis based on bit error rate (BER) versus signal to noise rate (Eb/No).

Peak-to-Average Power Reduction using Repeated Frequency Domain Filtering and Clipping in OFDM

The Orthogonal Frequency Division Multiplexing is one of the widely used modulation techniques in the broadband wireless technology. One of the main problems of the OFDM is the high peak-to-average power ratio of transmitting signal due to the superposition of many subcarriers. This paper presents a new proposed peak-to-average power ratio reduction technique, which Repeated frequency domain filtering and clipping over LET channel and compare with Repeated clipping and frequency domain filtering (RCF) technique. The paper highlights the performance and advantages of the proposed technique. The simulations show that the proposed technique realizes an improved PAPR and BER.

Green Wireless-Optical Broadband Access Network: Energy and Quality-of-Service Considerations

Growing energy demands in the information and communication technology (ICT) sector have been recognized as a major challenge worldwide. Researchers have been actively working to address this challenge, and the major focus centers around improving the energy efficiency of access networks, which are known for consuming about three-quarters of the total network power. Among various access networks, the hybrid wireless–optical broadband access network (WOBAN), which combines a passive optical network (PON) with broadband wireless technology, is highly regarded for its enormous capacity, cost efficiency, and ease of deployment. To develop a green WOBAN, it is important to focus on reducing its power consumption, and in this work, we present an efficient resource management technique for WOBAN that reduces the power consumption of the optical line terminal (OLT) and optical network unit (ONU) by introducing sleep modes for the OLT and ONU, based on the service class and traffic load. Moreover, it considers the quality-of-service requirement of each service class. Simulation results confirm that our proposed solution can save a significant amount of power in the WOBAN network without sacrificing the quality of service of end applications.

A Review on Methodologies for CapacityImprovement with Minimum Delay in WMN

In recent years there is explosive growth towards wireless broadband technologies which accelerating the need to design an efficient “last mile” access network in a cost-effective manner. Wireless Mesh Network (WMN) is emerging as promising technology for many useful applications. Over the past decade the size, cost and power requirements of radios has declined, enabling multiple radios to be contained within a single mesh node, thus allowing for greater modularity each can handle multiple frequency bands and support a variety of functions as needed such as client access, packet forwarding and scanning with minimum relays between nodes in wireless network. In order to making cost –efficient network different routing protocols are proposed. In this paper after analysing the different methodologies we use improved methodology that will not only find the shortest path but also making an efficient network by minimizing the delay from source to destination nodes in wireless network.

A novel networking architecture for mobile content delivery in urban transport systems

Today, the media content delivery in intermittent connected networks has become increasingly critical. This paper studies content exchange among mobile commuters in urban transport systems. Our work is inspired by two facts: (1) the commuters in urban transport systems tend to take regular routes to the same place every weekday and their paths exhibit a high degree of temporal and spatial regularities; (2) the rapid development of broadband wireless technologies such as IEEE 802.11n makes fast data transfer possible. We first propose a new disconnection-tolerant network infrastructure, which reinforces the connectivity of intermittent connected mobile commuters and uses store-and-forward routers to increase their encounter opportunity, and in turn achieves efficient media content delivery among them. Then a router-centric prediction method is designed to collect passengers' historical path information to determine the best delivery scheme. We evaluate the feasibility and the performance of the proposed infrastructure as well as the delivery scheme, using real data set from an urban transport system. The simulation results demonstrate the proposed system is highly practical in terms of the memory usage of routers and the maximum achievable data transfer rate.

Improvement in the Performance of WiMAX with Channel Equalizers and Space Time Block Coding Techniques Using Simulink

WiMAX is a coming forth broadband wireless technology that considered as one of the most prominent solution to provide high speed data services. This paper addresses the design of WiMAX end to end physical layer (PHY) in Simulink with channel equalization and space time block coding techniques. The authors analyzed the performance of WiMAX PHY with decision feedback equalizers (DFE), linear equalizers and blind equalizers over AWGN and multipath faded channels. Results include MISO channel power spectral density (PSD), antenna amplitude/PSD/phase difference, multipath faded and AWGN channel's effect on the transmitted signal and the performance of proposed equalizers on the received signals. This paper concluded that the linear equalizers have higher frame error rates (FER) than DFE. However, blind equalizers have higher FERs compared to conventional equalizers with better spectral efficiency as they need no training sequence.

Performance Analysis of Service Based Scheduler in LTE OFDMA System

Long Term Evolution (LTE) is the wireless broadband technology developed by Third Generation Partnership Project (3GPP) to support higher data rate. Resource scheduling in LTE plays an important role in deciding the overall network performance. In this paper, a new scheduling approach called Service Based Scheduler (SBS) is proposed that is suitable for real time services. In this method, two tag values called maximum tag value (Tmax) and minimum tag value (Tmin) are estimated for the packets based on the type of bearers. Tmax is calculated for Guaranteed Bit Rate (GBR) bearers and Tmin is calculated for non GBR bearers. Then, separate ascending sorted lists are formed for Tmax and Tmin. The packets from the Tmax list are allocated first in spite of users' channel condition. After the allocation of packets from Tmax list, if the current Transmit Time Interval (TTI) has more resources, then packets from Tmin list are allocated strictly based on users' channel conditions. The proposed scheduling approach provides better performance for real time services compared to other schemes like Proportional Fairness (PF), Modified Largest Weighted Delay First (MLWDF), Exponential rule (EXP rule) and Logarithmic rule (LOG rule).

Special Issue on Recent Innovations in Wireless Software-Defined Radio Systems

In wireless communications, the need to process and to exchange large amounts of real-time data is steadily increasing, but on the other hand the availability of spectral resources remains tightly limited. Innovative broadband wireless technologies are required which exploit the given frequency spectrum as efficiently and as effectively as possible. In the Special Issue of the Springer Journal of Signal Processing Systems at hand various disciplines of efficiency and effectiveness in the context of Software-Defined Radio (SDR) technologies are discussed. This Special Issue contains in total seven articles which are categorized into two sets. The first set of four articles puts emphasis on topics in the areas of Cognitive Radio, Dynamic Spectrum Access, and Spectrum Sensing. Thus, this selection of articles focuses on the efficient and effective use of spectral resources. Because frequency spectrum is well known to be scarce and limited, it becomes a resource of increasing value. The rapidly growing demand for higher data throughputs in wireless communications does not allow operators any inefficient use of spectrum anymore. Two promising approaches to tackle the spectral efficiency issue are Cognitive Radio (CR) and Dynamic Spectrum Access (DSA). A Cognitive Radio is capable of learning and adapting to its transmission environment. Taking e.g., Spectrum Sensing results into account, the decisions for accessing the scarce frequency spectrum in the most flexible, efficient, and effective manner are made. Cognitive Radios exploiting Spectrum Sensing and Dynamic Spectrum Access are typically based on SDR technology. The second set of three articles puts particular emphasis on topics in the areas of SDR Implementation of Wireless Communications. This selection addresses the challenges of implementation efficiency and effectiveness of 2G and 3G standards like GSM EDGE, LTE, and WiMAX. Especially in wireless communications these challenges have a growing importance, e.g., in order to increase battery time of modern SDR-based platforms. Such SDR platforms are typically based on heterogeneous multi-processor hardware architectures hosting General Purpose Processors (GPP), Digital Signal Processors (DSP), Field Programmable Gate Arrays (FPGA) and sometimes even more specific processing elements. Each type of processor has a specific advantage in one or the other performance criterion like energy consumption, flexibility, processing time, throughput, waveform portability, components reusability etc.Whenever a waveform shall be implemented on an SDR, the system designer has to find the best possible trade-off between all of these, partly conflicting, criteria.

Simulation and Implementation of an Integrated TDOA/AOA Monitoring System for Preventing Broadcast Interference

The rapid development of wireless broadband communication technology has degraded the location accuracyperformance of radio monitoring stations worldwide that use signal angle of arrival (AOA) location technology, and thestations in Taiwan are no exception. In this study, a Federal Communications Commission F(50, 50) broadcastpropagation prediction methodology was applied to determine the coverage area of installed TDOA-based monitoringstations in Tainan (i.e., southern Taiwan) metropolitan area. The simulation results indicated that 3 TDOA-basedlocation stations are required to achieve a coverage diameter of 20~30 km. Subsequently, 3 TDOA-based radiomonitoring stations [Luzhu, Tainan Gaote, and Tainan health stations (Jinkang)] were installed to locate the radiotransmitter that was the source of broadcast interference in Taiwan by monitoring the frequency modulation ofbroadcast stations at 88.3, 91.5, 89.1, and 91.9 MHz in the Tainan metropolitan, rural, and urban areas, respectively.In this study, the proposed integrated TDOA/AOA location technology was implemented in Taiwan for the first timeaccording to International Telecommunications Union requirements. The location accuracy was within 950 m (50%circular error probability) under multipath conditions in the metropolitan area.

Analytic Evaluation and Experimental Validation of a Network-Based IPv6 Distributed Mobility Management Solution

Mobile Internet traffic is growing steeply, mainly due to the deployment of new broadband wireless technologies and the ever increasing connectivity demand coming from new services being available to mobile users. Current mobile network architectures rely on centralized mobility protocols which intrinsically pose enormous burdens on the central anchors, both in terms of connectivity needs and user mobility management. In order to face these issues, a new paradigm, called Distributed Mobility Management, is being explored, based on flattening the network architecture by deploying multiple mobility anchors at the edge of the network. In this article we conduct an analytic and experimental evaluation of a network-based IP distributed mobility management solution that leverages Proxy Mobile IPv6 protocol operations. We develop an analytic model of the signaling and packet delivery costs, as well as the handover latency of both Proxy Mobile IPv6 and our distributed solution. We have also implemented a Linux-based prototype of our proposal, which has been used to experimentally assess the handover latency in a real IEEE 802.11 scenario. Finally, we use the results obtained from the analytic and experimental performance to evaluate the benefits that could be achieved by deploying a distributed mobility management solution.