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In this paper, we investigate the maximum inter-site distance (ISD) for performing joint signal processing between cooperative base stations. As a metric, we use the maximum excess delay measured at 95% point of the cumative power delay profile from all base stations. For the distance-dependent channel parameters, we consider Greenstein's statistical propagation model, which we extended for broadband...
For automotive applications car to infrastructure wireless communications enable delivering infotainment services such as location based information, voice calls and video streaming. Those services require a reliable high data rate connection which could be provided by cellular LTE which supports channel adaptive MIMO transmission. However, at the automotive side, confined space is available to accommodate...
This article describes a measurement campaign performed by a real-time UWB MIMO channel sounder and an analysis of measured date aimed at localisation applications in the automotive scenario. Measurements were done in the 3.5 GHz -10.5 GHz frequency band in different antenna constellations and propagation environments. Basic statistical analyses offer better insight into the measured radio channel...
The main goal of the IEEE 802.11n standard is to achieve more than 100Mbps of throughput at the MAC service access point. This high throughput has been achieved via many enhancements in both the physical and MAC layers. A key enhancement is frame aggregation which reduces the overheads and increases the channel utilization efficiency. The MAC layer defines A-MSDU and A-MPDU frame aggregations in which...
This paper proposes a cross-layer design (CLD) framework called channel-aware buffer unit multiple access (C-BUMA) for improving wireless local area network (WLAN) performance. In the framework, the radio propagation (i.e. PHY layer) is combined with the medium access control (MAC) protocol for packet transmissions. By sharing channel information with the MAC protocol, the approach reduced unnecessary...
In order to facilitate the deployment of wireless systems in medical environments, indoor channel measurements at 2.4 GHz have been performed in a hospital. In these environments, monitoring applications are of particular interest, where a patient carrying a medical body area network (MBAN) transmits data to a fixed receiver. The receiving node may be placed in practice at different locations, for...
A new paradigm for wireless sensor networks (WSN) information gathering, called Collaborative Sampling is proposed in this paper. Collaborative Sampling is a distributed active sampling regime that requires that each sensor to coordinate the tasks of data sampling and dissemination through succinct collaboration with neighboring sensor nodes. This is made possible by exploiting the inherent correlation...
Next generation wireless networks will be heterogeneous, where several primary users (PU e.g. licensed users) and secondary users (SU e.g. unlicensed users) can operate in the same dynamic and reconfigurable networks at a given time. The major challenge in this heterogeneous radio environment is to enable the coexistence between PU and SU which will further improve the efficient use of radio spectrum...
The paper deals with a modified version of opportunistic scheduling algorithm that exploits multiuser diversity. It incorporates the proportional fairness scheduling policy with the first-in-first-out (FIFO) policy to obtain a hybrid policy that works well when the channel state information of each mobile user is not necessarily known. In the paper, it is proposed that the channel state information...
Several dynamic bandwidth allocation (DBA) protocols have been introduced to utilize upstream channel in Ethernet Passive Optical Networks (EPONs). In this paper, a novel MAC protocol, called Nearest First Scheme (NFS) is introduced. NFS can minimize end to end delay and packet drop ratio at ONUs. Additionally, NFS can relive the common drawback of offline scheduling, i.e., channel idle time. NFS...
Noncoherent receivers are the practical solutions for impulse radio (IR) ultra-wideband (UWB) systems due to their low-complexity and low-cost implementation. However, this simplicity is achieved at the expense of some performance degradation. In this paper, we propose the utilization of time reversal (TR) technique to improve the performance of a recently presented noncoherent detection scheme, called...
Vehicular Networks are more and more considerable recently. With the rapid advance of information technology, it becomes easy to support low cost inter-vehicle communication. In particular, the demand for delay sensitive applications, such as streaming media distribution, is increasing. However, due to the high mobility, links between roadside units and wireless nodes are intermittent, unreliable...
We consider wireless femtocell networks where scheduling of transmissions is coordinated across multiple cells to mitigate interference and deliver fairness and quality of service (QoS). Coordination across multiple cells entails (i) exchange of (serving and interfering) channel information and traffic priority (which is a function of packet delays, average rate, queue length), and (ii) signalling...
Due to the broadcast nature of wireless channels, neighbouring sensor nodes may overhear packets transmissions from each other even if they are not the intended recipients of these transmissions. This redundant packet reception leads to unnecessary expenditure of battery energy of the recipients. Particularly in highly dense sensor networks, overhearing or eavesdropping overheads can constitute a...
In a cognitive radio (CR) network, secondary users (SUs) are allowed to opportunistically access a licensed spectrum that is not currently being occupied by primary users. This paper is concerned with the problem of how to quickly and accurately locate an unoccupied channel or determine that there is no unoccupied channel, from multiple (yet finite) candidate channels for a SU with a single detector...
Seamless handoff support is an essential issue to ensure continuous communications in wireless mesh networks (WMNs). Due to the existence of multi-hop wireless links, traditional handoff schemes designed for single-hop wireless access networks can hardly guarantee the low handoff latency requirement in WMNs. Existing solutions on reducing the handoff delay in WMNs ignore one important factor for the...
A distributed dynamic slot assignment scheme for multi-channel Time Division Multiplex Access (TDMA) based wireless Ad Hoc networks is presented in this paper. As exclusive control channels are introduced, hidden terminals are enable to receive packet whereas transmit packets are avoided. Similarly, exposed terminals are enable to transmit packets while receive packets are avoid. Thus high efficient...
Fiber Channel is the new generation network and bus technology, with high property of good compatibility, low latency, high reliability, high fast transmission, distance transmission and so on. Based on periodic and event information, this paper took deterministic and stochastic Petri nets as a tool, to model a simulated FC-AE-ASM network in the Fiber Channel Avionics Environment. It also calculates...
The possibility of distributing data to all interested entities connected to a mobile system is a fundamental core function in future mobile ubiquitous class based applications. Unfortunately, its realization poses many problems especially due to the typically scarce resources. With the goal of enhancing scalability, this paper presents a novel data distribution infrastructure for wireless mobile...
As an emerging networking technology, cognitive radio networks (CRNs) have drawn immense attention in the wireless networking community. Since multimedia services have become widely popular among wireless communication services users, supporting those services over CRNs has become an interesting research topic in recent years. However, due to the random nature of the resource availability in CRNs,...
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