Radio over fiber, optical access networks, wireless broadband access technologies, OFDM systems, wireless technologies for developing communities, telemedicine Research Papers (original) (raw)

n this article the prospects and possibilities for creating an individual wearable system for monitoring the condition of a patient suffering from bronchial asthma and preventing attacks of the disease are discussed. As the basic method of determining the condition of the patient is considered the technique for determining the transmission coefficient of a certain frequency microwave signal through the chest. The proposed method is non-invasive and harmless and can be used for patients of all age groups.

- by and +2
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- Telemedicine, Allergic bronchopulmonary aspergillosis, Telemedicine Applications and e-Health Systems, Telemetry

"In this report, I will summarise current government initiatives on broadband at a regional and national level, and assess the implications for broadband supply and demand in the Wellington region. For each area surveyed within the... more

Apart from voice services, data made its foray in cellular networks with 2.5G networks. Today, with 3G network already in place, the data requirements of mobile subscribers is very high. With the increasing demand for mobile internet and rich data services such as streaming media for audio and video, this data requirement is expected to multifold in near future. Correspondingly the network operators have started looking for alternative means of satisfying these data needs. Among many alternatives, mobile data offloading (MDO) is the most promising one. This paper presents the extensive need, benefits, and technological solutions for MDO. Qualitatively, it is also shown that Wi-Fi, or 802.11 network is the most
promising technology for MDO. Also, to further popularize Wi-Fi as a candidate network for MDO, IEEE published the enhancements to the base IEEE 802.11-2007 standard in the form of its ninth amendment (i.e. IEEE 802.11u). Restricting the scope to beacon frame only, we show how this amendment supports interworking of 802.11 network with external networks. We also show the benefit of 802.11u compatible
Wi-Fi, as a candidate network for MDO, by modelling the problem of taking user's choice for assisting any vertical handover decision algorithm.

Nowadays, broadband access network has obtained
increasing attention among Internet users. High bandwidth
demands and the need on mobility of the network are factors
for the network design and architectures to be part of the hot
topics in the research area. Wireline optical and wireless
networks are two different architectures of broadband access
network which offer advantages over each other. Quality of
services (QoS) in telecommunication network has significant
role in the flow of data in the network, particularly in data
scheduling. This paper defines integrated optical wireless
broadband access network, describes QoS focusing on
integrated network and reviews some previous work on
scheduling algorithms.

This presentation reviews 5G RAN functional decomposition along with RAN architecture evolution before exploring technical solutions for fronthaul transport. The relative techno-economics are presented along with considerations based on... more

- by Andy Sutton
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- Mobile Technology, Mobile and Telecommunicaions, Optical Networks, Mobile Computing

Orthogonal frequency division multiplexing (OFDM) is a special case of multicarrier transmission which
transmits a stream of data over a number of lower data rate subcarriers. OFDM splits the total transmission bandwidth
into a number of orthogonal and non-overlapping subcarriers and transmit the collection of bits called symbols in
parallel using these subcarriers. This paper gives a total insight of various Peak -to Average Power Reduction (PAPR)
techniques and principles of OFDM systems used in wireless communications. The research paper places a focus also
on OFDM behaviors and techniques like Carrier Frequency Offset (CFO) estimation that improves performance of
OFDM for wireless communications. Finally, the paper provides a number of wireless communication standards and
many of the applications where OFDM systems are used.

- by Joan-Francesc Fondevila-Gascón
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- History, Music, Communication, Media Studies

This report paints a picture of First Nations and Inuit community-based broadband networks and information and communication technologies in Canada. It highlights the very different levels of broadband infrastructure and connectivity that exist across the country. Even at the end of the first decade of the 21st century, many of these communities remain unserved or underserved when compared to their neighbours in urban Canada. But despite a lack of abundant broadband infrastructure and robust connectivity services, in many cases these communities are planning, administering, managing and, sometimes, owning digital networks and technologies. They are also applying these technologies to deliver broadband-enabled public and community services in areas like health, education, government, culture and language. Despite decades of innovative, community-based work in this area, to our knowledge this is the first comprehensive study and record of these activities.

Setelah mempelajari modul ini peserta memahami dan mengetahui Arsitektur teknologi & Implementasi FTTX, serta mengetahui Jenis dan fungsi elemen Network FTTX baik di sisi Drop cable dan Building Network. Topik bahasan Definisi Fiber... more

With the advent of new communications technologies such as 5G, next-generation telecommunications systems and networks require high reliability. Radio over fiber technology is considered one of the best choices, which can take advantage of the benefits of optical fibers (low attenuation, high bandwidth (THz), long-distance, etc). In this case, we need to use other types of modulation, which have high spectral efficiency (SE), high capacity, a speed that addresses Gbits/s, and high performance. The objective of this master thesis is to propose and analyze the performance of radio over fiber systems used for the co-existence of 5G fronthaul and FTTH wireless access networks based on the use of dual polarization of digital modulations such as QAM, DP-QPSK, and DP-OFDM using WDM technique. Theoretically, this work will be done by mathematical analysis of our system, which will write a research report on this type of modulation and will use the OptiSystem software for simulation to evaluate the reliability of the system based on the constellation diagram, eye diagram, BER, Q factor, etc.

60 GHz technology offers various advantages over current or existing communications systems. One of the most important is the availability of at least 5 GHz of continuous bandwidth worldwide. While this is comparable to the unlicensed bandwidth allocated for ultra-wideband (UWB) purposes, the 60 GHz bandwidth is continuous and less restricted in terms of power limits. In fact, the large bandwidth at
60 GHz band is one of the largest unlicensed bandwidths being allocated in history.

Free Space Optics is a wireless means of transmitting data using optics, optical communication in line of sight is used, this paper uses laser technology to transmit data from one point to another, high data rates (Gbps) are guaranteed... more

The Internet of Things (IoT) incorporates multiple long-range, short-range, and personal area wireless networks and technologies into the designs of IoT applications. This enables numerous business opportunities in fields as diverse as e-health, smart cities, smart homes, among many others. This research analyses some of the major evolving and enabling wireless technologies in the IoT. Particularly, it focuses on ZigBee, 6LoWPAN, Bluetooth Low Energy, LoRa, and the different versions of Wi-Fi including the recent IEEE 802.11ah protocol. The studies evaluate the capabilities and behaviours of these technologies regarding various metrics including the data range and rate, network size, RF Channels and Bandwidth, and power consumption. It is concluded that there is a need to develop a multifaceted technology approach to enable interoperable and secure communications in the IoT.

Artificial intelligence in combination with modern technologies including medical screening devices has the potential to deliver better management services to deal with chronic diseases with higher accuracy, efficiency, and satisfaction. With the recent evolution in digitized data acquisition, computer vision and machine learning, AI solutions are spreading into areas which were previously examined by well-trained clinicians. Early diagnosis of diabetic retinopathy (DR) and foot ulcers (DFU) occurrence through image analysis is in high demand as many individuals are left without any supervision due to the limited resources such as trained clinicians or suitable equipment especially, in rural areas. Furthermore, the existing system will become even more insufficient as the number of people with diabetes increases. In this research paper, we propose a prototype that involves an autonomous system called an Intelligent Diabetic Assistant (IDA), which decides the diagnosis and the treatment prioritization depending upon the observations appeared in the screen. The IDA consists of knowledge-based modules for severity level-based classification, clinical decision support and near real- time foot ulcer detection and boundary screening. We use the System Usability Scale (SUS) in terms of performance; learn ability, and satisfaction to measure the usability of the IDA. The mean SUS score was 88.5, demonstrating good but not exceptional system usability. We perform our experiments with clinicians who have been involved in diabetic care.

A novel design based on integration of OFDM and FSO system is reported in this work to prolong the FSO link at high transmission rate under clear weather conditions and evaluates the performance of such hybrid systems using ODSB, OSSB and OTSB schemes. Simulations indicate that the hybrid OFDM-FSO promises considerably improved free space link with acceptable SNR and BER compared to traditional FSO systems.

This work is focused to carry out an investigation to estimate the performance of an OFDM-OSSB-RoF transmission system using different order of QAM sequence generator at high transmission rate. Further, the results are reported by compensating the degradations introduced by fiber dispersion using fiber Bragg grating (FBG) for the proposed Hybrid OFDM-RoF system and a comparison is presented for the performance of OFDM-RoF system with and without FBG. The results are reported by incorporating OSSB modulation scheme as it performs better ODSB modulation scheme as the later one is suffered, severely, with fading problems due to fiber dispersion. In case of hybrid RoF system with FBG, an improvement in SNR ratio and total power received is achieved in comparison to hybrid RoF system without FBG.

Radio-over-Free-Space-Optics (Ro-FSO) is a promising technology for future wireless networks. In this work, we have designed a hybrid orthogonal frequency division multiplexing (OFDM) Ro-FSO system for transmission of two independent channels by mode division multiplexing. Two independent 40 GHz radio signals are optically modulated at 20Gbps by mode division multiplexing of two laser modes LG00 and LG10 and transmitted over a free-space link of 20 km to 100 km. The performance of proposed Ro-FSO system is also evaluated under the effect of strong atmospheric turbulences.

- by Cotruta Victor
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- Wireless Communications, Wireless Sensor Networks, Wireless networks, Wi-Fi

Le présent rapport brosse le portrait des réseaux à large bande communautaires des Premières Nations et des Inuits ainsi que des technologies de l’information et des communications (TIC) au Canada. Il met en évidence des différences marquées au chapitre de l’infrastructure à large bande et des services de connectivité entre les provinces canadiennes. À la fin de la première décennie du XXIe siècle, nombre de ces communautés ne sont toujours pas desservies, ou encore sont mal desservies comparativement à leurs voisins des régions urbaines du Canada. Néanmoins, même si elles n’ont pas accès à une infrastructure à large bande très étendue ni à un large éventail de services de connectivité fiables, dans bien des cas, ces communautés planifient, administrent, gèrent et, parfois, possèdent des réseaux et des technologies numériques. Elles utilisent ces technologies pour offrir des services publics et communautaires à large bande dans des domaines comme la santé, l’éducation, l’administration, la culture et les langues. Malgré des décennies de travaux communautaires novateurs effectués dans ce domaine, il s’agit à notre connaissance de la première étude approfondie sur ces activités dont les résultats ont été consignés.

This paper reveals that nonlinear propagation is a critical problem for the long term evolution (LTE) technology based on the radio-over-fibre (RoF) system. Therefore, a direct modulation based frequency dithering (DMFD) method is proposed for nonlinear propagation compensation, namely the self phase modulation (SPM) and stimulated brillouin scattering (SBS). We found that DMFD method operates substantially different in RoF systems. The major difference is that DMFD signal frequency fd has to be much smaller than the RoF carrier frequency fRF; thus the condition of {fd << fRF} has to be stringently obeyed. Analysis of the optical launch power (OLP) with DMFD method reveals that the SBS threshold is above ~6 dBm for LTE-RoF system. In addition, we also unfold that DMFD method does not induce an additional distortion for the linear and optimum OLP regions, which are frequency chirp dependent. Hence the proposed method improves the LTE-RoF system without any shortcoming. Finally, at OLP values of 8 dBm and 10 dBm, LTE-RoF system exhibits an average error vector magnitude (EVM) improvement of ~4.32% and ~6.18%, respectively, for the 50 km transmission span.

- by Thavamaran Kanesan
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- Optical Fiber Communications, Nonlinear Optics, Long Term Evolution (LTE), LTE

To cope with the unprecedented growth of mobile
data traffic, we investigate the performance gains obtained from unifying coverage-centric 4G mobile networks and capacitycentric fiber-wireless (FiWi) broadband access networks based on data-centric Ethernet technologies with resulting fiber backhaul sharing and WiFi offloading capabilities. Despite recent progress on backhaul-aware 4G studies with capacity-limited backhaul links, the performance-limiting impact of backhaul latency and reliability has not been examined in sufficient detail previously. In this paper, we evaluate the maximum aggregate throughput, offloading efficiency, and in particular the delay performance of FiWi enhanced LTE-A heterogeneous networks (HetNets), including the beneficial impact of various localized fiber-lean backhaul redundancy and wireless protection techniques, by means of probabilistic analysis and verifying simulation, paying close attention to fiber backhaul reliability issues and WiFi offloading limitations due to WiFi mesh node failures as well as temporal and spatial WiFi coverage constraints.

This work is focused on to carry out a comparative investigation of wired and wireless OFDM–OSSB–RoF transmission system using 4 QAM sequence generator at high transmission rate. The results are also reported at different laser spectral-widths as it also plays an imperative role in reducing the degradations introduced by fiber dispersion for both the proposed hybrid OFDM–OSSB–RoF systems. An efficient improvement is reported after a range of 10–100 km for both the hybrid RoF systems on reducing laser spectral-width from 10 MHz to 100 kHz at the transmission rates of 10/20-Gbps.

- by Sushank Chaudhary
- •
- Optics, Optical Fiber Communications, Fiber Optics, Photonics

One of the problems in the new generation of radio over fiber networks that requires to be concentrated, is decreasing the quantity of bit error rate in the lowest power penalty. This works studies a new technology for increasing the capacity of radio network backbone transmission channels by combining the two particular radio signal and optical power technologies. This paper also evaluates the results of down-link 5Gbps OOK signal of four radio base stations over 50km dense wavelength division multiplexing single mode fiber. The outcomes show that the total received optical power penalty is about 0.2dB at bit error rate of 10-9 and quality factor of greater than 7. This amount of bit error rate can be supposed as a negligible value in the performance of radio over fiber system for multimedia and real time applications.

The role of Extinction Ratio to optimize Fiber Optic Channel Capacity for Long haul and high speed transmission

Growth in technology has led to unprecedented demand for high speed architectures for complex signal processing applications. In 4G wireless communication systems, bandwidth is a precious commodity, and service providers are continuously met with the challenge of accommodating more users with in a limited allocated bandwidth. To increase data rate of wireless medium with higher performance, OFDM (orthogonal frequency division multiplexing) is used. Recently DWT (Discrete wavelet transforms) is adopted in place of FFT (Fast Fourier transform) for frequency translation. Modulation schemes such as 16-QAM, 32-QAM, 64-QAM and 128-QAM (Quadrature amplitude modulation) have been used in the developed OFDM system for both DWT and FFT based model. In this paper we propose a DWT-IDWT based OFDM transmitter and receiver that achieve better performance in terms SNR and BER for AWGN channel. It proves all the wavelet families better over the IFFT-FFT implementation. The OFDM model is developed using Simulink, various test cases have been considered to verify its performance. The DWT-OFDM using Lifting Scheme architecture is implemented on FPGA optimizing hardware, speed & cost. The wavelet filter used for this is Daubechies (9, 7) with N=2. The RTL code is written in Verilog-HDL and simulated in Modelsim. The design is then synthesized in Xilinx and implemented on Virtex5 FPGA board and the results were validated using ChipScope.

One challenge for UHF RFID passive tag design is to obtain a low-profile antenna that minimizes the influence of nearbody or attached objects without sacrificing both read range and universal UHF RFID band interoperability. A new improved design of a RFID passive tag antenna is presented that performs well near problematic surfaces (human body, liquids, metals) across most of the universal UHF RFID (840–960 MHz) band. The antenna is based on a low-profile printed configuration with slots, and it is evaluated through extensive simulations and experimental tests.

- by Jorge Costa
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- Antennas, Antennas & Radio Wave Propagation, RFID, Microstrip Antennas and Arrays

With the materialization of light emitting devices for
solid state lighting, visible light communication (VLC) has
provided a prospect to realize low cost, high speed, power
efficient and secure data transmission in addition to lighting.
Incandescent and fluorescent light sources are being replaced by
light emitting diodes (LED) which are not only energy efficient
but also help in reducing carbon dioxide CO2 emission. In this
paper, experimental results are being presented using a new
protocol for VLC and the optimum placement of the LEDs within
the transmitter to maximize the transmitter foot prints

Text available in Portuguese only: O trabalho examina os limites e os possíveis efeitos sociais e políticos do Plano Nacional de Banda Larga (PNBL). A discussão considera as transformações
testemunhadas no cenário das telecomunicações brasileiras ao longo da segunda metade do século XX. Por um lado, o fim do monopólio estatal das telecomunicações e a venda de empresas públicas para a iniciativa privada trouxeram maiores investimentos em infraestrutura. Por outro lado, a atuação dos agentes do Estado brasileiro ainda não parece ter surtido o efeito desejado no que se refere à universalização e ao barateamento na oferta de serviços de telecomunicações. O PNBL foi lançado
com o objetivo de combater tais dificuldades. O projeto, no entanto, peca no que se refere (1) à baixa velocidade de conexão a ser oferecida aos usuários; (2) aos preços pouco atrativos; e (3) à ausência de reflexão acerca da importância da neutralidade da rede. Defende-se que apenas ao contemplar tais aspectos o Plano poderá garantir inovação, crescimento econômico, pluralidade informacional e liberdade de acesso.

- by Francisco Paulo Jamil Marques
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- Political Economy, Digital Divide, Internet Studies, Digital Media

Radio-over-fiber (ROF) is a promising technology to achieve future broadband access requirements with reliability, transparency and flexibility. We propose a novel full-duplex bi-directional radio-over-fiber (ROF) system transmitting 10 Gb/s differential phase-shift keying (DPSK) signals at the central office (CO) for downstream and ON–OFF keying (OOK) re-modulation of the downlink carrier at the base station (BS) for upstream. As the same optical carrier is used for both uplink and downlink, no additional light source is required at the BS, which significantly reduces the cost, improves the wavelength utilization efficiency and simplifies the overall system. The simulation results show that the downstream 10 Gb/s DPSK data and the upstream 1 Gb/s OOK data can transmit over 50 km single-mode fiber successfully without dispersion compensation. The results show that this scheme provides a practical solution to meet the data rate and cost requirement of tomorrow's ROF access networks.