Broadband Wireless Technology Research Articles

Design and analysis of an IEEE 802.21-based mobility management architecture: a context-aware approach

Broadband wireless technologies will soon become an integral part of daily life. In this paper we present the design rationale of a context-aware mobility management architecture for seamless handover in heterogeneous networks. Our proposal is a new cross-layer and interactive approach to seamless handover of users and their services. We present a simple though effective analytical model in typical deployment scenarios in heterogeneous networks with the use of the IEEE Media Independent Handover services. Such analytical model is used to evaluate the resulting handover delay when deploying common mobility protocols in our architecture, such as Mobile IP, Hierarchical MIP, and Proxy MIP.

Studi Perancangan Jaringan Worldwide Interoperability For Microwave Access (Wimax) Di Area Banyumas

At present the need for higher internet connection along with the age which is growing so fast. Then there is the latest breakthrough in telecomunications that is WiMAX technology is a wireless broadband technology reffered the IEEE 802.16 standard. WiMAX technology comes with a network of excellence in aspects of data access speed, wide area coverage and the presence of QoS is can allocate frequencies in accordance with user needs using OFDM technology. WiMAX technology can reach area far as 50 kilometers, also allows user equipment (customer premise equipment or CPE) to get a broadband connection without having a direct path (non line of sight, NLOS) to the base station (BS) and provides a total data rate of up to 75 Mbps. Results of this Final project assumed that the area where will be design is Banyumas district. Then final project results of the PRX -100.31 dB; the Total Margin of 23.56 dB; Path los of 134.5 dB; gamma (?) of 4.375; Frequency correction factor (?PLf) of 0,36; antenna correction factor (?PLh) is -3,25; Radius Cells (d) is approximately 1995 meters; area of cell is at 10,34010495 km2 and the number of cells 133

Next-generation QoS control architectures for distribution smart grid communication networks

This article presents a proposal for applying the ITU-T end-to-end QoS control architecture for next-generation networks to the distribution smart grid communication networks. We propose the use of a QoS broker device to enhance the QoS in the smart grid electrical distribution access domains by providing a centralization of QoS management. Our proposal takes decisions based on current network data traffic flows, existing QoS policies and customer service level agreements and facilitates interoperability with other technology domains in order to achieve seamless end-to-end QoS. The key feature of this end-toend QoS control is the mapping of QoS parameters mainly between broadband power line and wireless technologies that principally serve the distribution smart grid but it can be applied to other communication technologies as well.

Here We Are! Where Are We? Locating Mixed Reality in The Age of the Smartphone

Mixed reality (MR), from location- and context-aware systems through immersive augmented reality applications, has been studied in research labs for more than two decades. With the advent of the modern smartphone, and the rapid adoption of wireless broadband technologies, this research is moving out of the lab and into the real world. Beyond just providing a platform for MR to reach a broad range of users, the capabilities and limitations of the smartphone provide a set of constraints on what kinds of applications can and cannot be delivered to consumers that have fundamentally changed how researchers think about MR. We examine previous definitions of MR, and reimagine the term as a class of experiences occurring in an ecosystem consisting of the smartphone, the cloud, and the user. Using a selection of current MR applications as a lens, we identify three key areas of continuing evolution and suggest how the development of a next-generation MR environment can help us channel the future growth of MR in research, industrial, and consumer communities.

Mobile telemedicine for moving vehicle scenarios: Wireless technology options and challenges

Recent studies conclude that patient survival during a health emergency situation depends on the effective pre-hospital healthcare. Mobile telemedicine exploits different wireless network technologies in order to tackle this problem. This paper looks into the case of mobile telemedicine service provision in a moving vehicle (ambulance). The special characteristics and requirements of this operational scenario are discussed in terms of benefits and limitations in conjunction with the application of existing wireless communication systems in this case. Moreover, emerging wireless broadband communication systems and spectrum access technology are considered in the same context, in an attempt to further improve service provision and face future challenges.

Performance Analysis of Channel Assignment Scheme in Wimax

Along with information technology of flourishing, the popularization rate of wireless communication equipment is higher. However, WiMAX is the one of new broadband wireless technologies. The performance of mobile WiMAX system is highly dependent on channel assignment scheme because frequency spectrum is finite in wireless communication systems. There are two exist channel assignment scheme in WiMAX namely No Prioritized Scheme (NPS) and Reserved Channel Scheme (RCS). In this paper propose new channel assignment scheme namely Temporal Reserved Channel Scheme (TRCS) for improve performance of channel assignment scheme in WiMAX. Performance of channel assignment scheme in WiMAX depend on four probabilities such as Blocking Probability (pb ), Handover Failure (ph ), Forced Termination Probability (pft ) and Probability of Not Completed Calls (pnc ). KeywordsWiMAX, NPS, RCS, TRCS, Channel assignment scheme, pb , ph , pft , pnc .

To Study Channel Estimation Techniques In Mimo Ofdm System

A multiple-input multiple output (MIMO) communication system is used with orthogonal frequency division multiplexing(OFDM) modulation technique to achieve high and reliable data rate transmission over broadband wireless channels. The need of MIMO OFDM is important because of only MIMO improves the system capacity without additional bandwidth.(1) The performance of MIMO-OFDM system is evaluated on the basis of Bit Error Rate(BER) and Mean Square Error(MSE). The correct channel estimation requires channel response of subcarriers between the pilot tones. Usually the received signal is distorted by channel characteristics. To recover the transmitted bits channel effects must be estimated. By orthogonality principle, each component of received subcarrier is to be expressed as product of transmitted signal and channel frequency response of subcarriers. So, the transmitted signal is recovered by estimating the channel response just at each subcarrier. Generally, data signal as well as training signal, or both , can be used for channel estimation. In this Paper, we will discuss channel estimation techniques in brief. The estimation of channel estimation technique will be carried out through MATLAB simulation.(3) Orthogonal frequency division multiplexing (OFDM) is based on multicarrier communication techniques. The idea of multicarrier communications is to divide the total signal bandwidth into number of subcarriers. A disadvantage of the OFDM approach, is the increased complexity over the conventional system caused by employing N modulators and filters at the transmitter and N demodulators and filters at the receiver. However, this complexity can be removed by the use of the FFT and IFFT at the receiver and transmitter, respectively. The MIMO OFDM system consists of Nt transmit and Nr receiving antenna. Training symbols are used along with pilots in frequency domain.(2) MIMO OFDM is a new broadband wireless technology used in channel estimation due to high data rate and because of its robustness against multipath fading effects. The major problem faced in channel estimation is how to obtain the channel state information correctly. In training symbol based channel estimation the two types of arrangements are used along with the pilot symbol assisted modulation(PSAM) technique. One is the block type and the another is comb type, the block type arrangement channel estimation is done under the assumption of slow fading(channel transfer function not changes rapidly) while in comb type, the interpolation(linear and cubic spline) is used for the estimation. The another techniques are LS(least square) and MMSE(minimum mean square estimation) are widely used for estimation. In the LS estimation, the estimation is done in such a way such that the cost function should be minimized. This method is simple to use. In MMSE, the estimation vector is used by orthogonality principle. This technique is better but more complex than LS estimation. In DFT based, effect of noise outside the maximum channel delay is eliminated and in this, performance is improved as compare to LS and MMSE estimation. In Decision Directed(DD) estimation, the coefficients of channel are updated after the initial estimation is made with preamble or pilots.(2) It uses the detected signal feedback to for tracking the time varying channel to detect the signal.

WiMAX-UMTS Converging Architecture with IMS Signalling Analysis to Achieve QoS

The third-generation partnership project (3GPP) and 3GPP2 have standardized the IP multimedia subsystem (IMS) to provide ubiquitous and access network-independent IP-based services for next-generation networks via merging cellular networks and the Internet. The IEEE 802.16 worldwide interoperability for microwave access (WiMAX) promises to provide high data rate broadband wireless access services. The IP Multimedia Subsystem (IMS) seems to be the technology that will prevail in Next Generation Networks (NGN s), since the interworking environment and the service flexibility that this technology offers to the currently deployed wireless broadband technologies makes it appealing to users, service developers and network operators. In this paper we propose a heterogeneous network model based on the IMS that integrates the Worldwide Interoperability for Microwave Access (WiMAX), Universal Mobile Telecommunications System (UMTS) and provides guaranteed QoS. In this paper, hybrid interworking architecture to integrate 3G (UMTS) and WiMAX networks with QoS is proposed. Moreover, IMS based signaling along with QoS algorithm was analyzed for UMTS and WiMAX interworking Architectures. QoS parameters such as Ethernet load and delay, IP Packet end to end delay, TCP delay, Active TCP connection count and TCP retransmission count, Email download response and upload response, Voice jitter, Voice packet delay variations and voice traffic received were analyzed.

Protecting H.264/AVC Data-Partitioned Video Streams over Broadband WiMAX

Broadband wireless technology, though aimed at video services, also poses a potential threat to video services, as wireless channels are prone to error bursts. In this paper, an adaptive, application-layer Forward Error Correction (FEC) scheme protects H.264/AVC data-partitioned video. Data partitioning is the division of a compressed video stream into partitions of differing decoding importance. The paper determines whether equal error protection (EEP) through FEC of all partition types or unequal error protection (UEP) of the more important partition type is preferable. The paper finds that, though UEP offers a small reduction in bitrate, if EEP is employed, there are significant gains (several dBs) in video quality. Overhead from using EEP rather than UEP was found to be around 1% of the overall bitrate. Given that data partitioning already reduces errors through packet size reduction and differentiation of coding data, EEP with data partitioning is a practical means of protecting user-based video streaming. The gain from employing EEP is shown to be higher quality video to the user, which will result in a greater take-up of video services. The results have implications for other forms of prioritized video streaming.

Performance Evaluation of the DVB-RCT Standard for Interactive Services

The European Digital Video Broadcasting-Return Channel Terrestrial (DVB-RCT) standard represents a wireless In-Band return channel solution based on Orthogonal Frequency Division Multiple Access to provide interactive services in Digital Video Broadcasting-Terrestrial (DVB-T) systems. In this paper, the performance of DVB-RCT standard is evaluated and compared with another possible wireless broadband technology to convey feedback traffic. Firstly, the performance of a DVB-T/RCT single cell system has been evaluated using an interactive traffic source model assuming uniform geographical user distribution with adaptive modulation and coding. The obtained results have confirmed the suitability of using DVB-RCT as a technological solution for the return channel in both rural and urban areas. Additionally, the performance of DVB-T/RCT system has been compared to IEEE 802.16-2004 using a published performance evaluation research of the latter as a benchmark. Assuming that the 802.16 published results are correct, such comparison shows a clear advantage of the DVB-T/RCT system.

Performance Evaluation of Secure Video Transmission over WIMAX

WiMAX is a wireless digital communication system based on the IEEE 802.16 standard which provides broadband wireless Internet access at very high rates that is up to 70 Mbps or a data rate of about 3 Mbps within a radius of 30-mile (data rate increases as the distance decreases). With the rapid increase in the wireless broadband use, the need for wireless fixed and mobile metropolitan area networks has ever been increasing. Multimedia communications, including audio and video are highly bandwidth demanding and error sensitive. When the coverage area of the wireless network technology is as high as with WiMAX, security becomes one of the most important issues.WiMAX, both mobile and fixed, has many attractive features such as connection-oriented MAC layer, provision of the Quality-of-Service (QoS) for different applications, efficient mobility and power save mode features. Needless to say, all these attractive features must be protected against malicious activities by security mechanisms.Providing secure multimedia communications by using a broadband wireless technology like WiMAXis likely to be challenging due to time or space overhead that occur. Security mechanisms might increase packet sizes thus delay, jitter and throughput are increased. In this paper, we evaluate the performance of secure video transmission over WiMAX networks under different cryptographic algorithms by using the OPNET simulator. The outcome of the results show negligible overhead introduced by the security extensions giving credence to their application in security sensitive scenarios.

A network algorithm for 3D/2D IPTV distribution using WiMAX and WLAN technologies

The appearance of new broadband wireless technologies jointly with the ability to offer enough quality of service to provide IPTV over them, have made possible the mobility and ubiquity of any type of device to access the IPTV network. The minimum bandwidth required in the access network to provide appropriate quality 3D/2D IPTV services jointly with the need to guarantee the Quality of Experience (QoE) to the end user, makes the need of algorithms that should be able to combine different wireless standards and technologies. In this paper, we propose a network algorithm that manages the IPTV access network and decides which type of wireless technology the customers should connect with when using multiband devices, depending on the requirements of the IPTV client device, the available networks, and some network parameters (such as the number of loss packets and packet delay), to provide the maximum QoE to the customer. The measurements taken in a real environment from several wireless networks allow us to know the performance of the proposed system when it selects each one of them. The measurements taken from a test bench demonstrate the success of our system.

How Evolving Network Access and Network Management Technologies are Redefining the Competitive Wireless Markets

This paper examines some of the key problems users encounter when accessing current generation wireless networks. Using a case study of a hypothetical user, the authors explore the emerging services and the new broadband wireless network technologies necessary to carry them out. This paper analyses the issues associated with an observed trend in the industry that exposes potential changes to the long-term, rigid commercial relation between wireless providers and users: as a result of a range of evolved broadband wireless access standards and technologies, autonomic communications and policy-based management, and new pricing schemes, consumers will likely face new opportunities to enter short-term and spot contracts with the new wireless providers. This new landscape also allow multiple competing Access Providers (APs) to dynamically assign prices, and poses new and interesting challenges to the regulatory function. The paper also discusses a framework for the integration of heterogeneous technologies and management policies based on the network context that make up this emerging, hybrid wireless landscape, and describes the economic characteristics of new markets likely to arise.

Performance Analysis of IEEE 802.16d using Forward Error Correction

Problem statement: Worldwide Interoperability for Microwave Access is the broadband wireless technology for terrestrial broadcast services in Metropolitan Area Networks. This BWA technology is based on Orthogonal Frequency Division Multiplex (OFDM) technology and considers the radio frequency range up to 2-11 GHz and 10-66 GHz. The objective of this research work is the performance analysis of AWGN, SUI-1 and SUI-2 fading channels in IEEE802.16d using FEC to improving BER at different SNR under QPSK digital modulation technique. Approach: Channel coding part is composed of three steps randomization, Forward Error Correction (FEC) and interleaving. FEC is done in two phases through the outer Reed Solomon (RS) and inner Convolutional Code (CC). The implementation and analysis will be made on using MATLAB simulation. Results: In this analysis the Bit Error Rate under QPSK modulation technique over AWGN, SUI-1 and SUI-2 fading channel with encoder for a SNR value of 5dB but in the case of without encoder is found SNR value of 9dB,10dB and 8dB respectively. Conclusion: It was concluded that all the three fading channel had same SNR with FEC .The optional Block Turbo Coding (BTC) can be implemented to enhance the performance of FEC.

WIMAX Basics From PHY Layer to Scheduling And Multicasting Approaches

WiMAX (Worldwide Interoperability for Microwave Access) is an emerging broadband wireless technology for providing Last mile solutions for supporting higher bandwidth and multiple service classes with various quality of service requirement. The unique architecture of the WiMAX MAC and PHY layers that uses OFDMA to allocate multiple channels with different modulation schema and multiple time slots for each channel allows better adaptation of heterogeneous user’s requirements. The main architecture in WiMAX uses PMP (Point to Multipoint), Mesh mode or the new MMR (Mobile Multi hop Mode) deployments where scheduling and multicasting have different approaches. In PMP SS (Subscriber Station) connects directly to BS (Base Station) in a single hop route so channel conditions adaptations and supporting QoS for classes of services is the key points in scheduling, admission control or multicasting, while in Mesh networks SS connects to other SS Stations or to the BS in a multi hop routes, the MMR mode extends the PMP mode in which the SS connects to either a relay station (RS) or to Bs. Both MMR and Mesh uses centralized or distributed scheduling with multicasting schemas based on scheduling trees for routing. In this paper a broad study is conducted About WiMAX technology PMP and Mesh deployments from main physical layers features with differentiation of MAC layer features to scheduling and multicasting approaches in both modes of operations.

ICI Mitigation for OFDM Using PEKF

Orthogonal frequency division multiplexing (OFDM) is widely known as the promising broadband wireless communication technology due to the high spectral efficiency and robustness to the multi-path interference. However, the inter-carrier interference (ICI) caused by Doppler frequency offset is an important issue for OFDM in high mobility. In this paper, the method to mitigate ICI for OFDM system is investigated, and a novel ICI mitigation method using planar extended Kalman filter (PEKF) is proposed to reduce the ICI effects. Simulation results demonstrate that the proposed ICI mitigation method in this letter outperforms traditional ICI mitigation methods.

WiMAX for development

This paper discusses WiMAX (Worldwide Interoperability for Microwave Access), an emergent broadband wireless technology, and examines its suitability to developing countries. Previous technologies have not fulfilled the promise of increasing connectivity in developing countries, largely due to the high-cost of the technologies and the unsuitability of the technologies to local conditions. WiMAX has emerged as a genuine contender to fill the connectivity gap in developing countries. In this paper we discuss the characteristics of the technology, outline how it can be used to enhance community connectivity and identify some of the issues surrounding WiMAX deployments. We also discuss the implications of WiMAX for ICT for development research.

Study of Access Algorithms in Wireless Network

The measure to improve the performance of the wireless network channel is of great significance to the building in the wireless network. Due to IPv6 Agreement is the agreement for the next generation network and the core of it, IPHC header compression technology provides IPv6 basic headers and expanding headers with a good support, so we adopt IPHC header compression scheme which groups the data that need to transmitting, introduce retransmission mechanism and header request mechanism to make IPHC have much compression effect on headers. But IPHC header compression scheme is hard on signal channel, it required that loss rate of transportation link is a little lower. In order to let IPHC better adapt to wireless link, compression based on link state is offered: Using simple portioned Markov model to check channel error rate, adopting RTS/CTS access mechanism to search for link state. Apply OPNET simulation software to imitate and finally achieve the desired target. In past two decades, computer network got rapid development, with the application of computers wider and wider. But because of being limited by areas and time, users couldn’t surf on the Internet, communicate with each other, and transport messages at any time and at any place. In this case, the wireless network developed, wireless network technology also produced therewith. Computer wireless network technology included IEEE802.11 collection [1], bluetooth technology, infrared technology, and broadband wireless technology afterwards and so on. Wireless communication technology contained CDMA, GSM, etc [2-5]. According to access ways, wireless access technology was divided into fixed wireless access technology and mobile wireless access technology with many small parts. Wireless access system consisted of wireless base station, wireless base station controller, operation maintenance center and user units. User units which contained single units and multiunits were connected directly with user terminals. Base station, which provided signal-sending and signal-receiving services for users in one district, was controlled by the controller called center station facility to provide an interface with base station side and operation maintenance center, wireless signal channel control and base station monitor, complete the connection of exchanges and routers. Operation control centre is responsible for operating and maintaining wireless access system machines and managing daily network operations.

WINSE: WiMAX NS-2 extension

The IEEE 802.16 standard defines a wireless broadband technology called WiMAX. When compared with other wireless technologies, it introduces many interesting advantages at PHY, MAC, and QoS layers. Heavy simulations are needed to study the performance of IEEE 802.16 and propose further enhancements to this standard. Link-level simulations are not always sufficient, while system-level simulators are not always accurate enough to capture MAC and transport protocol details. We implemented an 802.16 extension for the NS-2 network simulator. It includes upper PHY modeling, almost all of the features of the 802.16 MAC layer, as well as the QoS framework. This article describes the implemented features and simulation methodology, while sharing our experience that can be used with other NS-2 modules. There is also an overview of the past and ongoing research.

Technology and market conditions toward a new competitive landscape in the wireless access market

This article argues that the wireless telecommunication market is about to witness a shift in business models and market structure as a result of the deployment of new broadband access technologies, spectrum management techniques, policy-based network management, and the drive of new entrants to compete against the incumbents. The article discusses four agents of evolutionary changes: a range of broadband wireless access standards and technologies that are front-runners in the industry's efforts to embody the next generation of wireless networks; new provider-customer relationships facilitated through changes in the usual contract patterns that will allow consumers to enter short-term and spot contracts with the new wireless providers; an overview of the current debate on spectrum management; and an explanation of how autonomic communications and policy-based management would support the new structure. Finally, the article asserts the necessity for the integration of the heterogeneous technologies that make up this emerging, hybrid wireless landscape, and describes the economic characteristics of a new competitive scenario.