A survey and comparison of multichannel protocols for performance anomaly mitigation in IEEE 802.11wireless networks

SUMMARYThis paper studies four aspects of multipath propagation with randomly distributed scatterers: (i) Gaussian and hyperbolic time-of-arrival (ToA) probability density functions (pdfs); (ii) theoretical bounds on the ToA pdfs; (iii) geometric pdfs in multipath propagation via Gaussian and hyperbolic scattering channels; and (iv) implementation of selective combining diversity as a method to decrease propagation delay, thus improving transmission performance. The Gaussian and hyperbolic scattering channels are employed to model random scatterers between a base station and a user equipment. One-dimensional and threedimensional results of Gaussian and hyperbolic ToA pdfs are reported. Detailed discussions are given.

Section: Bounds On Time-of-arrival Probability Density Functionsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

On geometric statistics with diversity in multipath scattering channels

Lê

2012

“…and avoiding duplicated frame transmission. The core idea behind this strategy is to exploit both time diversity and frequency diversity to send frames over high quality channels [30], increasing the capacity and the range of communications in mesh networks, reducing the collisions occurrence. It consists in temporarily delaying outgoing frames (usually control frames) so that they can be inserted in the next outgoing data frame, reducing the overhead over the access and utilization of the medium.…”

Section: Opportunistic Forwardingmentioning

confidence: 99%

“…Smart antennas and directional antennas. The core idea behind this strategy is to exploit both time diversity and frequency diversity to send frames over high quality channels [30], increasing the capacity and the range of communications in mesh networks, reducing the collisions occurrence. Briefly, directional antenna takes advantage of the PHY geometry of the antenna to provide a transmission power gain because energy is focused in a narrow direction rather than spread (e.g., in omnidirectional antennas).…”

Section: Network Coding Increases Transportationmentioning

confidence: 99%

A review of scalability and topological stability issues in IEEE 802.11s wireless mesh networks deployments

Sampaio

Souto

Vasques

2015

Scalability and topological stability are two of the most challenging issues in current wireless mesh networks (WMNs) deployments. In the literature, both the scalability and the topological stability of WMNs are described as likely to suffer from poor performance due to the ad hoc nature of the underlying IEEE 802.11 mechanisms. The main contribution of this article is a comprehensive review of the main topological stability and scalability-related issues in IEEE 802.11s-based networks. Moreover, the most relevant proposed solutions are surveyed, where both the drawbacks and the merits of each proposal are highlighted. At the end of the article, some open research challenges are presented and discussed. It is expected that this work may serve as motivation for more and deeper research on these issues to allow the design of future more stable and scalable IEEE 802.11s mesh networks deployments. 672 S. SAMPAIO, P. SOUTO AND F. VASQUES Figure 1. IEEE 802.11s network elements described in the standard [5].are combined with node H as it provides connectivity to the BSS B3-so, acting as mesh gate-and also connects the MBSS to a non-802.11 LAN, so acting as a portal. Note that any mesh gate is also a mesh STA.The aforementioned mesh properties enable, among other, fast deployment, low installation cost, and reliable communication. Consequently, their application spans a wide range of application domains from broadband home, community, and neighboring-enterprise-metropolitan areatransportation systems to building automation, health, medical, and security surveillance networks [6]. Nevertheless, current IEEE 802.11s mesh network deployments are typically small-sized, and it is yet unclear if they can scale to realistic network sizes, and support more demanding types of traffic such as real-time communication § .The challenge of introducing mesh capabilities in both medium access control (MAC) and physical (PHY) layers, while keeping compatibility with other IEEE 802.11 standards, makes the recently released IEEE 802.11s standard a hot topic of interest by researchers in the WMN's field. This article addresses the challenges to ensure scalability and topological stability in this networks.Scalability is a well-known issue in multi-hop networking, such as the IEEE 802.11s. Basically, when the size of the network increases, its performance behavior may significantly degrade [10]. It is an important factor for the performance of a mesh network [11]. However, this issue has not been studied in depth in the IEEE 802.11s; hence, there are still few research works in the literature about the scalability of IEEE 802.11s WMNs. The cause, as emphasized by Srivathsan et al. in [12], may be that network providers are beginning to implement their own mechanisms. Topological stability means that the self-organization process should be robust enough to sustain the assignment of links over a reasonable period without performance degradation or breakage; on the other hand, that the topology change and vicinity conditions (e.g., neighbors ...

“…The performance of the IEEE 802.11 DCF scheme has been extensively studied in the literature using different methods and simplifying assumptions. Because of the lack of a comprehensive model, this performance analysis has been going on up to now . Bianchi's 2D Markov chain model is the first and mostly used one (because of its simplicity) describing the BEB mechanism of DCF.…”

Section: Related Pieces Of Workmentioning

confidence: 99%

A comprehensive DCF performance analysis in noisy industrial wireless networks

Maadani

Motamedi

2014

Summary The use of wireless technology in industrial networks is becoming more popular because of its flexibility, reduction of cable cost, and deployment time. Providing an accurate model to study the most important parameters of these networks, the timeliness and reliability, is essential in assessing the network metrics and choosing proper protocol settings. The Institute of Electrical and Electronics Engineers (IEEE) 802.11 is a common and established wireless technology, and several analytical models have been proposed to assess its performance; however, most of them are accurate only for a limited network situation, especially data networks that have large packet payloads and are used at high signal to noise ratios, and cannot be applied to study the performance of industrial networks that have short packet lengths and are used in harsh and noisy environments. In this paper, a novel three‐dimensional discrete‐time Markov chain model has been proposed for the IEEE 802.11‐based industrial wireless networks using the distributed coordination function as the medium access control mechanism in the worst‐case saturated traffic. It considers both causes of the backoff freezing: busy channel and the successive interframe space waiting time. In this way, it provides a much more accurate estimation of the channel access and error probabilities, resulting in a more accurate network parameter calculation. Also, based on the proposed model, a comprehensive packet delay analysis, including average, jitter, and cumulative distribution function, has been provided for the near 100% reliable industrial scenario and error‐prone channel condition, which in comparison with similar pieces of work provides much more accurate results. Copyright © 2014 John Wiley & Sons, Ltd.