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The minimization of the overall power consumption of wireless networks while satisfying a certain throughput and error rate constraint is investigated. The total power dissipation includes the radiated power as well as the circuit power consumption. In the context of battery operated short range communication, where low power, low cost and small size are key requirements (e.g. standard IEEE 802.15...
Shortest link scheduling (SLS) in multihop wireless networks under physical interference model is notoriously hard to resolve and been studied only recently by a few works. Most of the obtained approximation bounds grow linearly with the number of links, and many are only valid with single-hop wireless networks, and some claimed approximation bounds are even false. This paper conducts a rigorous algorithmic...
It is known that in a cognitive random wireless network, the aggregate interference from secondary network is not Gaussian. Using Shannon's bound for the capacity of general additive channels, Gaussian interference/noise is the worst case due to its maximum entropy property which leads to minimum capacity. Therefore, it is favorable to have the distribution of interference as far from Gaussian as...
A severe spectrum shortage for wireless communication systems poses the spectrum overlapping and the interference problem with a significant performance degradation. To avoid this problem, it is essential to employ the techniques for interference mitigation. The goal of this paper is to investigate the performance of some interference mitigation techniques in the systems using Viterbi decoding, i...
Communication between two neighboring nodes is the most basic operation in wireless networks. Yet very little research has focused on the local delay, defined as the mean time it takes a node to connect to a nearby neighbor. This problem is non-trivial when link distances are random but static, as is the case when the node distribution of a static network is modeled as a stochastic point process....
This paper addresses multiple access in MIMO wireless networks. It compares two distributed interference alignment techniques, in space and in frequency, that both aim at removing interferences through orthogonalization. The theoretical advantages and drawbacks of each technique are highlighted. Then, the multiplexing gain and the computational complexity are analytically evaluated. It is shown that...
This paper investigates stability and robustness of a gradient-type power control algorithm for multicell CDMA wireless communication networks in the presence of time-delays and disturbances. The time-delays in individual communication channels between mobiles and base stations are allowed to take place independently. The disturbances represent power noises, unmodeled secondary interference and variation...
This paper presents an outdoor-to-aircraft measurement campaign conducted inside a long range Airbus A340-300 aircraft in order to evaluate the attenuation induced by the haul of the aircraft. The obtained results can be used to perform an interference study and assess whether the aircraft on-board network interferes to the terrestrial links. The minimum aircraft attenuation was found 15.5 dB. This...
Multi-channel design has received significant attention for low-power wireless networks (LWNs), such as 802.15.4-based wireless sensor networks, due to its potential of mitigating interference and improving network capacity. However, recent studies reveal that the number of orthogonal channels available on commodity wireless platforms is small, which significantly hinders the performance of existing...
A cognitive radio wireless network is investigated, in which a number of primary users (PUs) transmit in orthogonal frequency bands. There are also a number of secondary users (SUs) in the network, which monitor transmission opportunities in these frequency bands by collaboratively detecting whether each PU is transmitting. Each SU can participate in detecting only one PU's transmission at a time...
For wireless networks, traditional multihop routing, digital network coding (DNC) and physical-layer network coding (PNC) do not make full use of nonorthogonal signal subspace. We develop an active physical-layer network coding (APNC) strategy, introducing bi-directional interference to both destinations in a cooperative two-way relay channel (CTRC), which works on symbol level and uses arbitrary...
We study the rate region of a simplified wireless network for a given degree of interference, considered as noise, and power constrains. The network nodes use a specific modulation scheme with a specific bit error rate and a constant bandwidth. We define the necessary conditions that maximize the system's sum rate for a 2-link interference channel and provide criteria under which simultaneous link...
In this paper, we consider a cellular network assisted by fixed relay stations (RS), which are used by mobile stations (MS) to access the base station (BS) via a relaying strategy, namely Amplify-and-forward (AF) and Compress-and-forward (CF). We analyze the achievable sum-of-rates for uplink communications. It is assumed that mobile signals and relay signals are emitted on orthogonal bands, with...
The code division multiple access (CDMA) technology has been recently introduced into mesh wireless networks for improving channel efficiency. The existing approaches, however, do not maximize the capacity of a CDMA system, because the sender transmits to one receiver only. In this paper, we explore novel approaches to allow multiple data frames be transmitted from a sender to multiple receivers simultaneously...
The paper addresses the problem of interference modeling for wireless networks. Two axiomatic frameworks are known from the literature: (1) standard interference functions introduced by Yates in [JSAC 1995], and (2) general interference functions proposed by the authors in their previous work. In this paper, both frameworks are analyzed and compared. It is shown that (1) is contained in the more general...
In this paper, we consider a cooperative relaying scenario with multiple sources transmitting to one or more destination nodes through several relay terminals. Each relay is equipped with multiple receive and transmit antennas. We assume that the relays can estimate their uplink (relay-destination) channels with enough accuracy and that they have access to the training sequences transmitted by the...
We study a multiple-source, single-destination wireless network that uses scheduled access as the channel-access method. Unlike many other studies of scheduled access, which are based on the use of a collision channel, we use a physical channel model that includes other-user interference, fading, and background noise. Our primary performance measure is throughput, which is the average number of packets...
The spectrum scarcity, which is a serious problem in wireless communication, shows the extreme importance of spectrum sensing technologies. For the traditional spectrum sensing algorithms, they are very difficult to have a good tradeoff between accuracy and simplicity. This paper is based on the application of Goertzel algorithm to the cyclostationary feature detector, which makes fast-searching and...
The impulsive interferences are not negligible in many communication channels, such as power line channels. During the initialization of Turbo iterative decode algorithm, e.g., message passing algorithm for Low-Density Parity-Check code's decoder, it is necessary to estimate parameters of channel to retrieve the prior information from the received signals. Performances of the detector/estimator based...
We propose QUEST (QUality ESTimation), a new method that accurately estimates IEEE 802.11 wireless link quality with no in-band signaling overhead. Existing link quality estimation methods either are based on hello exchanges by fixing or varying transmission rates or rely on the history (e.g., delivery ratio) of previously sent data packets in a per-rate/-neighbor manner. QUEST on the other hand,...
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