The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
The base station in IEEE 802.16, or WiMAX, networks allocates contention-based time slots for the mobile stations to transmit their requests for additional bandwidth. Using a technique called subchannelization, multiple concurrent transmissions by mobile stations can be admitted by the base station during the same contention period. For transmission during this period, each station employs a contention-resolution...
In this paper we propose a novel technique for efficient video distribution over WiMAX networks. The technique incorporates resource distribution, scheduling and content-aware streaming of video taking advantage of a flexible QoS functionality offered by WiMAX. The proposed technique was thoroughly investigated using NS-2 software package under various real-life scenarios which included streaming...
In this paper, we present a review of automatic repeat request (ARQ) and hybrid ARQ (HARQ) mechanisms implemented or proposed in beyond 3rd generation (B3G) wireless systems based on OFDMA. In particular, we will focus on part of the IEEE 802.16 standard family (IEEE 802.16-2005, IEEE 802.16m) and on 3GPP Long Term Evolution (LTE). In the second part of this overview, some performance curves show...
The seamless integration of heterogeneous wireless access networks is currently one of the issues of major interest in the field of telecommunication systems. In an early future technologies like UMTS, WLAN and WiMAX will give broadband access to users that perform their voice/video calls or data sessions without knowledge of the specific technology their terminals are using, following the paradigm...
In current wireless standards like 3GPP LTE or IEEE 802.16 / WiMAX multiple access is based on orthogonal signalling using single-carrier frequency-division multiple access (SC-FDMA) or orthogonal frequency-division multiple access (OFDMA). Links between a base station and different terminals use mutually orthogonal radio resources. This paper studies potential gains in average cell throughput by...
System capacity is an important factor that affects the performance of WiMAX system where the amount of data that can be delivered to the end user is determined based on the system capacity and users QoS requirements. This scenario is even more complex when multi-hop relays are introduced into the network whereas the user access capacity decreases with the increase of hop number. In order to maintain...
Providing guaranteed quality-of-service (QoS) for resource-hungry multimedia applications over wireless fading channels is challenging. Traditional layered architecture fails miserably in providing the QoS requirement of high throughput, low latency demand of these kinds of applications in wireless mobile networks. Cross-layer design approaches are critical for efficient utilization of the scarce...
This paper represents high speed and high throughput pipelined Fast Fourier Transform and its inverse (FFT/IFFT) for Mobile Wi-MAX. Modified architecture also provides concept of local ROM module and variable length support from 128~2048 point for FFT/IFFT. UMC 0.18 ??m is used to design the same. FFT/IFFT chip consumes 266.81 mW at 40 MHz, 130.74 mW at 20 MHz and 65 mW at 10 MHz for length of 2048...
In this paper, we propose a framework to enhance user perceived quality in a multihomed terminal. Based on the observed media independent handover parameters from all the interfaces, the terminal is made aware of the performance of the different access networks and it can intelligently select the interface to send out the data packets. Several schemes, for the purpose of load balancing, are defined...
As one of the effective way to overcome the digital divide issue in the lightly populated area, the BWA (Broadband Wireless Access) system is expected and field trials have been conducted extensively in Japan. This paper introduces the results of BWA field experiments conducted in a typical intermediate and mountainous area in Japan. In the BWA network, WiMAX units are used as relay stations and R-LAN...
Mobile WiMAX has been introduced for next generation broadband wireless access systems, and it has been designed to provide various multimedia services through highspeed wireless Internet access. However, since IEEE 802.16e standard, international standard of mobile WiMAX, defined only hard handover as mendatory, Mobile Station (MS) cannot transmit or receive packets during handover procedure. Thus...
Through tailoring individual core to best fit dedicated applications, heterogeneous multi-core architectures can maximise performance while mitigating area costs and power consumption. This paper introduces heterogeneous multi-core architectures using coarse-grained dynamically reconfigurable processors. The multi-core system has been tailored for the performance intensive WiMAX transmitter. An exploration...
The IEEE 802.16 standard, also known as WiMAX, has emerged as an exciting technology for broadband wireless communications with potentials to offer high throughput and support high bandwidth demanding applications. WiMAX, however, has yet to prove its effectiveness when the end terminals are not fixed and have the capacity to move from one place to another at different speeds. Recent studies suggest...
We present active measurement results from a commercial IEEE 802.16/WiMAX-based network, with primary focus on TCP performance. We compare four TCP variants, namely New Reno, Cubic, Vegas and Veno, using throughput, round-trip time (RTT), and retransmission rate metrics. While all TCP variants achieve similar throughput, they do so in different ways, with different impacts on the network performance...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.