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In underwater acoustic sensor networks, the solution to augment sensor nodes' life time is crucial due to the difficulties in retrieving discharged sensor nodes. Thus, many energy efficient MAC protocols have employed mainly logical ways, such as sleep mode, hand-shaking signaling between nodes, and scheduling of transmission time, rarely using the physical characteristics of underwater acoustic channels...
We consider the performance of small-scale heterogeneous cooperative networks in which some nodes can transmit and/or receive using channels not available to other nodes, i.e., multimodal communication networks. As an example, we assume the presence of an additional wired channel in a conventional diamond relay network operating under the Laneman protocol, and we find analytical expressions for outage...
Transmission power control can significantly improve energy-efficiency of wireless sensor network communications. Power consumption models are typically based on dependence of channel attenuation on distance. However, in practice, information on distance is usually not available and the dependence of channel attenuation on distance is not sufficiently accurate. Therefore, we propose more accurate...
Recently, multipath in wireless channels has shown an interesting aspect. It has been found that wireless channels may provide a common reciprocal source of randomness for any two communicating nodes. This seems particularly interesting for secret key generation in wireless networks. In this paper, we consider the randomness property of wireless channels and present an intelligent algorithm for key...
We propose the maximum a posteriori (MAP) detection of the misbehaving relay that injects false data or adds channel errors into the network encoder in multiple access relay networks. The proposed scheme does not require sending extra bits at the source and is optimal in the sense of minimizing the probability of incorrect detection. We derive the probability of false alarm and misdetection, taking...
In this paper a new employment of the Reverberating Chamber (RC) as test facility for comparing modulation schemes used in modern wireless applications, is proposed. The robustness of GMSK and PSK signals to very-noisy environments emulated in RC is evaluated in terms of constellation and Bit Error Rate (BER) of the received signals. Experiments accomplished at Università di Napoli Parthenope (formerly...
Wireless devices are often connected to power outlets in residential data and smart-home networks. As a result, physical layer performance can be improved by using the power distribution tree as a diversity channel. This paper proposes a hardware-efficient, low intermediate-frequency (low-IF) transceiver architecture which allows existing wireless protocols to be used over both wireless and power-line...
In cognitive radio networks, a cognitive source node typically requires two essential phases to complete a cognitive transmission process: the phase of spectrum sensing with a certain time duration to detect a spectrum hole (thus also referred to as spectrum hole detection phase) and the phase of data transmission through the detected spectrum hole. In this paper, we focus on the analysis of cognitive...
The IEEE 802.15.4a standard for wireless sensor networks is designed for highly accurate ranging with impulse radio Ultra Wideband (UWB) signals. The standard is designed for coherent and non-coherent (energy detector) receivers, thus the choice of complexity is left to the implementer. In this paper, the maximal operating distance is analyzed for ranging, using a coherent receiver and an energy detector...
It has been proven that the IEEE 802.16 broadband wireless access (BWA) network is the most preferable next-generation network with the well defined quality of service (QoS) framework. Due to lack of the scheduling algorithm for the guaranteed QoS in the IEEE 802.16 standard, many results for the scheduler of the IEEE 802.16 BWA network have been proposed. However, for the downlink transmission with...
Multiple-input and multiple-output (MIMO) is one of the key component in wireless standards. Wireless standards exploit MIMO to enhance user experience by improving the data rate and reliability of the link. Multiple-input and multiple-output (MIMO) systems formed by multiple transmit and receive antennas can improve performance and increase capacity of wireless sensor networks. In this Paper, the...
Opportunistic relaying has been recently proposed to eliminate the need of symbol synchronization and challenging code design in distributed space-time coded (DSTC) cooperation yet achieving the same diversity multiplexing tradeoff. In opportunistic relaying, the relay terminal that possesses the best relay-destination channel quality is selected by the destination for cooperative forwarding. Combining...
In novel underwater wireless sensor array network architecture (UWSAN), each sensor node is attached to a local sensor array which performs maximum likelihood direction of arrival (DOA) locally. Sensor nodes communicate via acoustic channel and exchange DOA estimate and received target signal energy. Global DOA based localization is combined with energy in a non-linear least square cost function to...
In a wireless sensor network, it is likely that the measurements of the sensors are correlated. Distributed source coding can be used to reduce transmission rate or mitigate the effects of the channel noise in the case of analog transmission. In this paper, we propose a novel scheme for implementing distributed source-channel coding based on analog mappings. We assume that an analog source is to be...
Widespread proliferation of competitive technologies in licence free Industrial, Scientific and Medical (ISM) radio band is squeezing the room in frequency, temporal and spatial domain for the reliable operation of low power, low cost, IEEE 802.15.4 devices. In this context, providing some intelligence to IEEE 802.15.4 devices to analyze the environment and find the least interfered channel can result...
Throughput and energy efficiency are two important parameters to evaluate the performance of a wireless sensor network (WSN). For WSNs involved in varying channel conditions packet transmission reliability can be affected. This results in increased number of retransmissions and therefore energy consumption, with low throughput. Making optimal choices for robust packet transmission in this scenario...
This paper presents a channel aware contention based forwarding scheme (CACF) for wireless sensor network (WSN). In order to improve the probability of correct packet transmission in wireless channel and ensuring successful contention, CACF selects the appropriate relay node by the integrated consideration of access probability, routing cost metrics and wireless channel characteristics. In the scheme,...
We address the problem of estimating a random field via a wireless sensor network. We use a Multiple Access Channel (MAC) as the basic building block for such a network. For Gaussian sources over Gaussian MACs, we show that Amplify and Forward scheme (AF) performs well in such sensor network scenarios where the battery power is at a premium. We then extend this result to the hierarchical network scenario...
This paper analyzes the use of link quality, based on the signal to noise ratio, as a metric to improve routing in multi-hop wireless networks. We compare the behavior and performance with those of other approaches, namely a simple minimum-hop selection process, as well as the expected transmission count (ETX) metric, which has recently gathered relevant attention from the scientific community. We...
This paper presents C-MAC, a new MAC protocol designed to achieve high-throughput bulk communication for data-intensive sensing applications. C-MAC exploits concurrent wireless channel access based on empirical power control and physical interference models. Nodes running C-MAC estimate the level of interference based on the physical signal-to-interference-plus-noise-ratio (SINR) model and adjust...
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