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A typical broadcasting protocol for wireless network usually involves fixed transmission power that covers, for example an area within 250 meters (m). However, it is often unnecessary to broadcast using fixed power because a node that needs to be covered may just be 100m away. By reducing the transmission power enough to cover this node, energy expenditure would be reduced, thus, prolonging the lifetime...
We investigate the performance of analog network coding (ANC) for multi-hop networks in this paper. With the amplify-and-forward (AF) protocol, relays broadcast the sum of two colliding signals to neighboring nodes, while the source node can subtract its own signal from the colliding signal to obtain the received information. We first give the transmission scheme expressions for the n-node m-frame...
One of the main motivations of wireless communication between vehicles is to establish a mutual awareness among vehicles. Such awareness is achieved through the periodic exchange of broadcast messages with information about the current position, heading or speed of a vehicle. The probability that neighboring vehicles receive such messages successfully depends on the current radio channel and network...
Relaying technique has been developed considerable attention in response to improve reliability and to extend wireless network coverage. One of conventional relaying technique, incremental relaying which uses limited feedback from the destination has attracted research attention because of performance and minimization of relay usage. Moreover, optimal power allocation for various relaying schemes...
Industrial wireless WIA-PA is the industrial wireless networking standard which is an emerging and used for process control. Real-time and reliable communication is the most important technical features of industrial wireless network. In this paper, through the analysis of the wireless network for industrial control and network architecture and protocols, combined with industrial wireless networks,...
In wireless scenarios a simple and effective method to increase the reliability for time-varying channels is the hybrid automatic repeat request (H-ARQ) protocol. Recently, a H-ARQ scheme with cross-packet channel coding (CPC) has been proposed to increase the maximum coding rate at which full-diversity can be achieved. In this paper, CPC based on turbo codes is analyzed with EXIT charts. This allows...
Leader-based protocols have been proposed for wireless networks such as 802.11 as an alternative approach to MAC layer ARQ. If based on feedback cancellation, such protocols may achieve low latency and high throughput at predictable reliability and superior scalability with respect to the number of subscribers. Especially for delay-bounded multicast A/V transmission these properties are highly desirable...
To exploit the strengths of both the physical and the protocol interference models and to understand the varying observations on the relative goodness of scheduling based on the two models in literature, we analyze how network traffic, link length, and wireless signal attenuation affect the optimal instantiation of the protocol model. We also identify the inherent tradeoff between reliability and...
The Transmission Control Protocol (TCP) was designed to provide reliable transport services in wired networks. In such networks, packet losses mainly occur due to congestion. Hence, TCP was designed to apply congestion avoidance techniques to cope with packet losses. Nowadays, TCP is also utilized in wireless networks where, besides congestion, numerous other reasons for packet losses exist. This...
We present a new protocol to cluster nodes of wireless networks. Our protocol ensures reliable message transmission in spite of collisions and transmission losses. We first present a geometric-probabilistic model to predict the optimal range for maximizing one-hop broadcast coverage in wireless networks as a function of range, sending rate and density. We use the above model to design a scalable clustering...
Recently, it has been received in the community that the link reliability is strongly related to RSSI (or SINR) and the external interference makes it unpredictable, but the unpredictability has not been fully explained yet. In order to examine the causes of the unpredictable link state, we first configured an empirical testbed, performed a measurement study, and observed that the link reliability...
Opportunistic networks represent a new frontier for networking research as due to node mobility the network might become disconnected. Such intermittent connectivity imposes challenges to protocol design, especially when information access might require the availability of updated information about resources shared by mobile nodes. An opportunistic network can be seen as a peer-to-peer network where...
Recently, the network coding in cooperative communications has been categorized into two mainstreams, Digital Network Coding (DNC) and Analog Network Coding (ANC), which we both discuss in the article. First a brief survey of these two sub-branches is given. Then, to the very wireless characteristics fading and interference, DNC and ANC network coding way were proposed respectively, which aims at...
Broadcast is an important primitive in wireless mesh networks (WMNs). Applications like network-wide software update require reliable reception of the content with low-latency and high scalability (i.e., utilizing little bandwidth resource). In reality, the link layer broadcast transmission in WMNs is unreliable, which makes these goals hard to be attained at the same time. In this paper, we consider...
The outage behavior of non-orthogonal amplify-and-forward (NAF) and orthogonal amplify-and-forward (OAF) relaying protocols over a general one hop asynchronous cooperative network is examined when orthogonal frequency division multiplexing (OFDM) is used to combat synchronization error among the relays. The relays are only allowed to preform linear transformations over the received signals. It is...
Wireless mesh networking is a promising, cost effective and efficient technology for realizing backhaul networks supporting high quality services. In such networks, multicast data are transmitted blindly without any mechanism protecting data from loss, ensuring data reception, and optimizing channel allocation. The multicast services may undergo, then, very high data loss ratio which is exacerbated...
In this paper, a video streaming system for education based on wireless mesh network is proposed. Wireless mesh network is a self-organizing, self-managing and reliable intelligent network which allows educators to deploy a network quickly whenever there is a need. Video streaming plays an important role in this system for multimedia data transmission. This new system adopts the scalable video coding...
Wired and wireless networks are significantly different in terms of bandwidth, speed, propagation delay, and channel reliability. In particular, packet loss due to bit corruption over wireless links may be misinterpreted by TCP as the indication of congestion that forces TCP to reduce its congestion window and enter the congestion avoidance phase, which reduces TCP's throughput dramatically. In this...
The following topics are dealt with: reliability; quality of service; computer networks; radio networks; telecommunication network management; communication theory; protocols; telecommunication network routing; OFDM systems; telecommunication channel; multimedia communication; and optical communication.
As wireless mesh networks become more popular, there exists a need to provide centralized management solutions, which facilitate network administrators to control, troubleshoot and collect statistics from their networks. Managing wireless mesh networks poses unique challenges due to limited bandwidth resources and dynamic channel quality. A robust management solution should function despite network...
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