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AL-FEC (Application-Layer FEC) is already in used for protecting streaming and file delivery services against packet losses in the field of wide-area multimedia broadcasting, such as in DVB-H and 3GPP MBMS (Multimedia Broadcast Multicast Service) mobile TV systems. However, it is still not a well-studied approach for applying AL-FEC to WiFi multicast since guaranteed bandwidth for a multicast service...
In this paper, we address the problem of guaranteed transmission of video flows in the context of WiMAX mesh networks for video surveillance purposes. The main design issue in such networks is to maximize the number of flows that can be accommodated in critical situations. Guaranteeing a throughput for individual flows in a multi-hop WiMAX network is a challenging task. We consider a specific dedicated...
In our earlier work, we described an optimization problem and corresponding scheduling algorithm aimed at obtaining maximum throughput guarantees in wireless networks. To further improve the short-term performance, we also proposed two adaptive versions of the optimal algorithm. Results from the simulations showed that the adaptive algorithms perform significantly better than other well-known scheduling...
Due to its advantageous properties in multipath propagation scenarios, the Orthogonal Frequency Division Multiple Access (OFDMA) radio transmission scheme is widely spread in current broadband wireless networks. Exemplary emerging systems based on this technology are the UMTS Long Term Evolution (LTE), Mobile WiMAX and some popular WiFi variants (e.g. IEEE 802.11n). Although analytical and simulative...
This paper presents the capacity analysis of a threshold-based multiuser scheduling scheme in broadband OFDMA systems. Fourth-generation (4G) systems such as the WiMAX and LTE have adopted the band adaptive modulation and coding (band-AMC) subcarrier permutation mode for the grouping of the physical subcarriers into logical subchannels assigned to users by the base station (BS) schedulers. In the...
The unprecedented growth in wireless communication is offering opportunities and challenges for educators. Thanks to technology advances and job opportunities, more and more students are interested in wireless communications courses. However, bridging the gap between classroom and real-world experience remains a challenge. Advanced undergraduate communications courses typically focus more on theory...
In this paper, we study the performance of some of the key scheduling algorithms such as Proportional Fair Scheduler, Modified Longest Weighted Delay First and Exponential Rule. We also propose a new algorithm called EXPQW, a variant of the Exponential rule which assigns weights to the subscriber stations based on their queue length and waiting time thereby ensuring fairness and quality of service...
The increase in mobile data usage is pushing broad-band operators towards deploying smaller cells (femtocells) and sophisticated access technologies such as OFDMA. The expected high density of deployment and uncoordinated operations of femtocells however, make interference management both critical and extremely challenging. Femtocells have to use the same access technology as traditional macrocells...
In 2011, a project under the Japan Ministry of Internal Affairs and Communications (MIC) conducted measurement campaigns for Worldwide Interoperability for Microwave Access (WiMAX) in different scenarios in order to verify and improve the existing deterministic methods for estimating WiMAX system coverage in Japan [1]. Both outdoor urban and outdoor-indoor scenarios were considered in that project...
The current convergence process in wireless technologies demands for strong efforts in the conceiving of highly flexible and interoperable equipments. This contribution focuses on one of the most important baseband processing units in wireless receivers, the forward error correction unit, and proposes a Network-on-Chip (NoC) based approach to the design of multi-standard decoders. High level modeling...
Multicast and Broadcast Service (MBS) is transmission method that multiple BS in the same geographical area compose the MBS zone to transmit the same data to multi users simultaneously. MBS users combine MBS signals which belong to same MBS zone. Therefore, MBS has a much better SINR performance than unicast service. Despite its greater efficiency, it is difficult to enable power control consider...
3.65 GHz Mobile WiMAX spectrum is often a better commercial solution due to its attractive licensing requirements, in spite of the slightly lower coverage area. However, no significant performance data has been reported for 3.65 GHz equipment behavior. In this paper, we have presented an in-depth analysis of a 3.65 GHz Mobile WiMAX solution. Our reported data can also contribute in performing link...
This paper deals with a wireless WiMAX transceiver analysis, including the baseband signal treatment blocks, a polar ΣΔ transmitter architecture and the wireless channel modeled according to the SUI models. The details of digital and analog baseband are described within this paper. The choice of the environmental conditions for the system verification is given in sense of two critical channel models...
A multi-access radio network that efficiently utilizes radio resources is a promising approach to flexible, reliable, high-capacity communication. Regarding cooperative controlling functionality in a heterogeneous radio network, two schemes are considered to be applicable to the efficient usage of multi-radio systems: link selection and link aggregation. This paper focuses on link selection and its...
In this paper, we conducted an experiment using a PC to evaluate the proposed novel selection policy for a communication system in heterogeneous wireless networks. It entailed the use of an analytic hierarchy process (AHP) algorithm that took the mobility of the user terminals into account. In particular, the AHP algorithm demonstrated an excellent improvement in overall performance with existing...
Electrical energy networks are increasingly making use of Information Technology to enhance the way in which the electricity delivery infrastructure operates. A ‘Smart Grid’ can be understood as an electrical network which uses applications that are somehow dependent on the exchange of information to enhance its operation. This paper evaluates telecommunications delivery technologies that are appropriate...
The present work proposes a communication system to ensure Internet connectivity and network transparency to a group of nodes within a vehicle in the heterogeneous wireless networks environment. It organizes routers and hosts located inside a vehicle into a mobile network. Each vehicle is equipped with multiple cares of addresses corresponding to multiple network interfaces. The proposed scheme provides...
In this paper we have given an improved model for throughput enhancement and optimal relay selection. We studied about increase in throughput and optimal relay selection. Here we deployed a base station connected to host-sever, group of relay stations and group of mobile stations that are moving at constant speed. The mobile stations and base stations are deployed based on our new adaptive deployment...
This paper describes both link budget analysis and field experimental results on a mobile WiMAX system deployed in Azumino city, the city scale of which is corresponding to suburban. Firstly, in this paper, the link budget analysis is performed in order to evaluate the system performance based on propagation distance, delay spread, average BER (Bit Error Rate) under a multipath fading environment,...
To better exploit the spectrum resources a wireless sensor network can be used to assists a secondary cognitive radio network by providing information about the current primary spectrum occupancy. In this paper we study the performance of the secondary network when it is co-located with and having similar cell size as a mobile primary network that uses a cellular reuse pattern with seven frequencies...
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