Throughput and Range Performance Investigation for IEEE 802.11a, 802.11n and 802.11ac Technologies in an On-Campus Heterogeneous Network Environment

This paper presents an analysis and measurement results for an experimental study on throughput, range and efficiency performance of IEEE 802.11a, 802.11n and 802.11ac standards in an indoor environment on a typical University Campus. The investigation considers a number of key system features including PHY layers mainly, Multiple Input Multiple Output (MIMO), Multi-User Multiple Input Multiple Output (MU-MIMO), Channel Bonding and Short-Guard Interval (SGI) in the heterogeneous wireless network. The experiment is carried out for the IEEE 802.11ac standard along with the legacy protocols 802.11a/n in a heterogeneous environment which is typically deployed on Campus. The results compare the maximum throughput of IEEE 802.11 standard amendments, in terms of theoretical and experimental throughput over TCP and UDP protocols for different set of parameters and features to check their efficiency and range. To achieve this desired goal, different tests are proposed. The result of these tests will help to determine the capability of each protocol and their efficiency in a practical heterogeneous on-campus environment

Towards a cloud‑based automated surveillance system using wireless technologies

Cloud Computing can bring multiple benefits for Smart Cities. It permits the easy creation of centralized knowledge bases, thus straightforwardly enabling that multiple embedded systems (such as sensor or control devices) can have a collaborative, shared intelligence. In addition to this, thanks to its vast computing power, complex tasks can be done over low-spec devices just by offloading computation to the cloud, with the additional advantage of saving energy. In this work, cloud’s capabilities are exploited to implement and test a cloud-based surveillance system. Using a shared, 3D symbolic world model, different devices have a complete knowledge of all the elements, people and intruders in a certain open area or inside a building. The implementation of a volumetric, 3D, object-oriented, cloud-based world model (including semantic information) is novel as far as we know. Very simple devices (orange Pi) can send RGBD streams (using kinect cameras) to the cloud, where all the processing is distributed and done thanks to its inherent scalability. A proof-of-concept experiment is done in this paper in a testing lab with multiple cameras connected to the cloud with 802.11ac wireless technology. Our results show that this kind of surveillance system is possible currently, and that trends indicate that it can be improved at a short term to produce high performance vigilance system using low-speed devices. In addition, this proof-of-concept claims that many interesting opportunities and challenges arise, for example, when mobile watch robots and fixed cameras would act as a team for carrying out complex collaborative surveillance strategies.Ministerio de Economía y Competitividad TEC2016-77785-PJunta de Andalucía P12-TIC-130

MIMO Hardware Simulator Using Standard Channel Models and Measurement Data at 2.2 and 3.5 GHz

20 pagesInternational audienceA wireless communication system can be tested either in actual conditions or by using a hardware simulator reproducing actual conditions. With a hardware simulator it is possible to freely simulate a desired type of a radio channel. This paper presents architectures for the digital block of a hardware simulator of MIMO (multiple-input multiple-output) propagation channels. This simulator can be used for LTE (long term evolution system) and WLAN (wireless local area networks) 802.11ac applications, in indoor and outdoor environments. The first architecture is appropriate for shipboard environments, while the second corresponds to outdoor-to-indoor environments and considers the wave propagation penetration within buildings. Measurements campaigns carried out at 2.2 and 3.5 GHz have been conducted to obtain the impulse responses of the channel using a MIMO channel sounder designed at IETR. The measurements are processed with an algorithm extracting the dominant paths. The architectures of the digital block are implemented on a Xilinx Virtex-IV FPGA (field programmable gate array). After the implementation of the impulse responses, the accuracy, the occupation on the FPGA and the latency of the architectures are analyzed

GaN-Based Micro-LED Visible Light Communication: Line-of-Sight VLC with Active Tracking and None-Line-of-Sight VLC Demonstration

abstract: Visible light communication (VLC) is the promise of a high data rate wireless network for both indoor and outdoor uses. It competes with 5G radio frequency (RF) system as well. Even though the breakthrough of Gallium Nitride (GaN) based micro-light-emitting-diodes (micro-LEDs) enhances the -3dB modulation bandwidth dramatically from tens of MHz to hundreds of MHz, the optical power onto a fast photo receiver drops exponentially. It determines the signal to noise ratio (SNR) of VLC. For full implementation of the useful high data-rate VLC link enabled by a GaN-based micro-LED, it needs focusing optics and a tracking system. In this dissertation, we demonstrate a novel active on-chip monitoring system for VLC using a GaN-based micro-LED and none-return-to-zero on-off keying (NRZ-OOK) modulation scheme. By this innovative technique without manual focusing, the field of view (FOV) was enlarged to 120° and data rates up to 600 Mbps at a bit error rate (BER) of 2.1×10⁻⁴ were achieved. This work demonstrates the establishment of a VLC physical link. It shows improved communication quality by orders, making it optimized for real communications. This dissertation also gives an experimental demonstration of non-line-of-sight (NLOS) visible light communication (VLC) using a single 80 μm gallium nitride (GaN) based micro-light-emitting diode (micro-LED). IEEE 802.11ac modulation scheme with 80 MHz bandwidth, as an entry level of the fifth generation of Wi-Fi, was employed to use the micro-LED bandwidth efficiently. These practical techniques were successfully utilized to achieve a demonstration of line-of-sight (LOS) VLC at a speed of 433 Mbps, and a bit error rate (BER) of 10⁻⁵ with a free space transmit distance 3.6 m. Besides this, we demonstrated directed NLOS VLC links based on mirror reflections with a data rate of 433 Mbps and a BER of 10⁻⁴. For non-directed NLOS VLC using a print paper as the reflective material, 195 Mbps data rate and a BER of 10⁻⁵ was achieved.Dissertation/ThesisDoctoral Dissertation Electrical Engineering 201

IEEE 802.11ac wireless delivery of 4kUHD video: The impact of packet loss

This paper examines the 4kUHD video quality from streaming over an IEEE 802.11ac wireless channel, given measured levels of packet loss. Findings suggest that there is a strong content dependency to loss impact upon video quality but that, for short-range transmission, the quality is acceptable, making 4kUHD feasible on head-mounted displays

MIMO Hardware Simulator: New Digital Block Design in Frequency Domain for Streaming Signals

11 pagesInternational audienceThis paper presents a new frequency domain architecture for the digital block of a hardware simulator of MIMO propagation channels. This simulator can be used for LTE and WLAN IEEE 802.11ac applications, in indoor and outdoor environments. It accepts signals in streaming mode. A hardware simulator must reproduce the behavior of the radio propagation channel, thus making it possible to test "on table" the mobile radio equipments. The advantages are: low cost, short test duration, possibility to ensure the same test conditions in order to compare the performance of various equipments. After the presentation of the general characteristics of the hardware simulator, the new architecture of the digital block is presented and designed on a Xilinx Virtex-IV FPGA. It is tested with time-varying 3GPP TR 36.803 channel model EVA and TGn channel model E. Finally, its accuracy is analyzed

Multivariate statistical technique over QoS variables to analyze video quality metrics on IEEE 802.11ac networks

[EN] We present the results from a measurementbasedperformance evaluation of wireless networks basedon IEEE 802.11ac standard in an indoor environment, withthe aim to analyze their performance under high definitionstreaming video applications. We focus our study on analyzingthe highest performance of these standards using off-theshelfequipment as well as the behavior of Quality of Servicevariables and how they affect to the video quality. Thus, wehave analyzed and measured these variables and have applieda multivariate statistical technique, called Factor Analysis,and finally discuss their behavior.This work was supported by the Universitat de Valencia under the projects UV-INV-PRECOMP14-207134, UVINVAE15-339582, by the Generalitat Valenciana under the project GV-2016-002 and by the Ministry of Economy under the project BIA2016-76957-C3-1-RGarcía-Pineda, M.; Felici-Castell, S.; Segura-Garcia, J. (2018). Multivariate statistical technique over QoS variables to analyze video quality metrics on IEEE 802.11ac networks. En XIII Jornadas de Ingeniería telemática (JITEL 2017). Libro de actas. Editorial Universitat Politècnica de València. 152-159. https://doi.org/10.4995/JITEL2017.2017.6572OCS15215