An Investigation into Signal Strength of 802.11n WLAN

With the continual improvement in IEEE 802.11 standards wireless networks are being deployed in ever increasing numbers. As technology advances the data rates and coverage of Wi-Fi increases and so the usage for different high bandwidth requirement applications increases. These enhancements to the technology do provide network design engineers with some significant problems when designing the network infrastructure. Prior to the installation of Access Points it is difficult to predict whether access can be guaranteed at specific locations. Additionally, to increase the level of security, it is often preferable, despite the use of security protocols, to ensure that the signal strength is not large enough to enable connection in areas other than those designated. Experience with existing equipment may not be sufficient to ensure a secure design. It is shown that it is likely that equipment built to the anticipated IEEE 802.11n specification that uses MIMO provide a far more complex situation than equipment designed to previous standards. By combining the theory of antennae and the measurement of the performance of equipment built to the IEEE 802.11n draft, it is possible to create a mathematical model that can predict the network coverage which should be extendable to the new standard. Additionally it is argued that due to the backward compatibility of equipment then the increased data rates are not going to be realised until the all intended clients have been upgraded

An RF-Isolated Real-Time Multipath Testbed for Performance Analysis of WLANs

Real-time performance evaluation of wireless local area networks (WLANs) is an extremely challenging topic. The major drawback of real-time performance analysis in actual network installations is a lack of repeatability due to uncontrollable interference and propagation complexities. These are caused by unpredictable variations in the interference scenarios and statistical behavior of the wireless propagation channel. This underscores the need for a Radio Frequency (RF) test platform that provides isolation from interfering sources while simulating a real-time wireless channel, thereby creating a realistic and controllable radio propagation test environment. Such an RF-isolated testbed is necessary to enable an empirical yet repeatable evaluation of the effects of the wireless channel on WLAN performance. In this thesis, a testbed is developed that enables real-time laboratory performance evaluation of WLANs. This testbed utilizes an RF-isolated test system, Azimuthâ„¢ Systems 801W, for isolation from external interfering sources such as cordless phones and microwave ovens and a real-time multipath channel simulator, Elektrobit PROPSimâ„¢ C8, for wireless channel emulation. A software protocol analyzer, WildPackets Airopeek NX, is used to capture data packets in the testbed from which statistical data characterizing performance such as data rate and Received Signal Strength (RSS) are collected. The relationship between the wireless channel and WLAN performance, under controlled propagation and interference conditions, is analyzed using this RF-isolated multipath testbed. Average throughput and instantaneous throughput variation of IEEE 802.11b and 802.11g WLANs operating in four different channels - a constant channel and IEEE 802.11 Task Group n (TGn) Channel Models A, B, and C - are examined. Practical models describing the average throughput as a function of the average received power and throughput variation as a function of the average throughput under different propagation conditions are presented. Comprehensive throughput models that incorporate throughput variation are proposed for the four channels using Weibull and Gaussian probability distributions. These models provide a means for realistic simulation of throughput for a specific channel at an average received power. Also proposed is a metric to describe the normalized throughput capacity of WLANs for comparative performance evaluation

An efficient genetic algorithm for large-scale planning of robust industrial wireless networks

An industrial indoor environment is harsh for wireless communications compared to an office environment, because the prevalent metal easily causes shadowing effects and affects the availability of an industrial wireless local area network (IWLAN). On the one hand, it is costly, time-consuming, and ineffective to perform trial-and-error manual deployment of wireless nodes. On the other hand, the existing wireless planning tools only focus on office environments such that it is hard to plan IWLANs due to the larger problem size and the deployed IWLANs are vulnerable to prevalent shadowing effects in harsh industrial indoor environments. To fill this gap, this paper proposes an overdimensioning model and a genetic algorithm based over-dimensioning (GAOD) algorithm for deploying large-scale robust IWLANs. As a progress beyond the state-of-the-art wireless planning, two full coverage layers are created. The second coverage layer serves as redundancy in case of shadowing. Meanwhile, the deployment cost is reduced by minimizing the number of access points (APs); the hard constraint of minimal inter-AP spatial paration avoids multiple APs covering the same area to be simultaneously shadowed by the same obstacle. The computation time and occupied memory are dedicatedly considered in the design of GAOD for large-scale optimization. A greedy heuristic based over-dimensioning (GHOD) algorithm and a random OD algorithm are taken as benchmarks. In two vehicle manufacturers with a small and large indoor environment, GAOD outperformed GHOD with up to 20% less APs, while GHOD outputted up to 25% less APs than a random OD algorithm. Furthermore, the effectiveness of this model and GAOD was experimentally validated with a real deployment system

Enhancements of minimax access-point setup optimisation approach for IEEE 802.11 WLAN

As a flexible and cost-efficient internet access network, the IEEE 802.11 wireless local-area network (WLAN) has been broadly deployed around the world. Previously, to improve the IEEE 802.11n WLAN performance, we proposed the four-step minimax access-point (AP) setup optimisation approach: 1) link throughputs between the AP and hosts in the network field are measured manually; 2) the throughput estimation model is tuned using the measurement results; 3) the bottleneck host suffering the least throughput is estimated using this model; 4) the AP setup is optimised to maximise the throughput of the bottleneck host. Unfortunately, this approach has drawbacks: 1) a lot of manual throughput measurements are necessary to tune the model; 2) the shift of the AP location is not considered; 3) IEEE 802.11ac devices at 5 GHz are not evaluated, although they can offer faster transmissions. In this paper, we present the three enhancements: 1) the number of measurement points is reduced while keeping the model accuracy; 2) the coordinate of the AP setup is newly adopted as the optimisation parameter; 3) the AP device with IEEE 802.11ac at 5 GHz is considered with slight modifications. The effectiveness is confirmed by extensive experiments in three network fields

Implementation of improvements of the Wi-Fi network of the RTBF and implementation of a Wi-Fi network for an “intelligent” building

Este Trabajo de Fin de Grado se ha realizado dentro de la Radio Televisión Belga Francófona (RTBF) en Bruselas. El objetivo de este proyecto es el diseño de una red Wi-Fi completamente confiable y de alto rendimiento para una de sus localizaciones. Para empezar, se completaron un estudio teórico y mediciones reales. La comparación entre el estudio teórico y práctico no estaba concluyente por lo que las predicciones teóricas se han modificado para corresponder a la realidad. Finalmente, la RTBF está construyendo un nuevo edificio en 2022 para el cual un estudio predictivo teórico se ha hecho para proporcionar una cantidad de puntos de accesos necesarios para una cobertura completa.This End-of-Grade work have been done inside the Francophone Belgian Radio-Television (RTBF) in Brussels. The goal of this Project is to design a fully reliable and performant Wi-Fi network for one of their localization. To begin with, a theorical study and real-life measurements were completed. The comparasion between the theorical and practical study was not concluding so the theorical predictions have been changed to correspond to reality. Finally, the RTBF is constructing a new building in 2022 for which a theorical predictive study have been done to provide the number of needed access points for a complete coverage.Grado en Ingeniería en Tecnologías de Telecomunicació

Analisis Simulasi Model COST-231 Multiwall Pathloss Indoor Berbasis Wireless Sensor Network pada Aplikasi Absensi Mahasiswa dengan Tag RFID Menggunakan RPS (Radiowave Propagation Simulator)

Wireless Sensor Network is a solution to solve cable-based network problems especially in attendance applications with RFID Tag. However, in this research, RFID Tag based on Wireless Sensor Network is implemented in indoor conditions that have higher path loss than in outdoor conditions. This paper analyzed the distribution of RSSI receipt of indoor COST231 Multiwall path loss model by using Radiowave Propagation Simulator (RPS) to model the indoor condition of the building as the actual conditions such as the size and the building materials. This Simulation use 3 Node Router and 8 End node of Wifi RFID Reader with WLAN 1EEE 802.11.n communication protocol at 2.4 GHz frequency. The simulation result shows that the mean and deviation standard values of RSSI at the scenario router node plus end node implemented condition is -46.94 dBm and 10,79, respectively. *****Wireless Sensor Network adalah solusi dalam mengatasi masalah jaringan berbasis kabel terutama dalam aplikasi absensi mahasiswa dengan Tag RFID. Namun, pada studi ini, wireless sensor network diimplementasikan pada kondisi indoor yang memiliki pathloss lebih tinggi dibandingkan pada kondisi outdoor. Penelitian ini menganalisis sebaran daya terima RSSI pada simulasi model indoor path loss COST231 Multiwall dengan menggunakan Radiowave Propagation Simulator (RPS) untuk memodelkan kondisi indoor gedung sesuai dengan kondisi sebenarnya, baik dari ukuran maupun bahan gedung. Simulasi menggunakan 3 Node Router dan 8 End node dari Wifi RFID Reader dengan protocol komunikasi WLAN 1EEE 802.11.n pada frekuensi 2,4 GHz. Hasil simulasi menunjukkan bahwa nilai rata-rata dan standar deviasi RSSI pada kondisi terimplementasi dari router node dan end node adalah -46,94 dBm dan 10,79 secara berturut-turut

When the Industry Goes Wireless: Drivers, Requirements, Technology and Future Trends

Non