Performance analysis of slotted fiber-optic code-division multiple-access (CDMA) packet networks

This paper examines code-division multiple-access (CDMA) techniques used in slotted fiber-optic packet networks. Since the inherent properties and signal processing of the conventional communication channels are different from those of the fiber-optic channels, new code sequences must be constructed for fiber-optic applications. The goal of our research is to analyze the performance of fiber-optic CDMA packet networks using code sequences with given orthogonality properties. © 1997 IEEE.published_or_final_versio

Performance analysis of unslotted fiber-optic code-division multiple-access (CDMA) packet networks

This paper examines code-division multiple-access (CDMA) techniques used in unslotted fiber-optic packet networks. Since the inherent properties and signal processing of the conventional communication channels are different from those of the fiber-optic channels, new code sequences must be constructed for fiber-optic applications. In unslotted systems, the exact solution is very difficult to obtain. Therefore, two approximation methods are presented to analyze the performance of such systems. Simulation is performed to verify the accuracy of the results.published_or_final_versio

Bidirectional link mock-up for avionics applications

Copper-based networks have been extensively employed on aircraft to ensure the avionics data-communications. Since the Airbus A380 development, Avionic Data Communication Network (ADCN) has been implemented to ensure transmissions between avionic equipment. This system is based on the Avionic Full Duplex Ethernet (AFDX), and transfers data at rates up to 100 Mb/s. The need of faster communications systems, up to 1Gb/s, has led to great interest in fiber optic based networks. Beyond higher data rates capabilities, the fiber optics have additional benefits, compared to electrical cables, in terms of weight saving and electromagnetic interference immunity which is strongly needed at gigahertz bandwidths. Multimode fibers (MMF) are becoming increasingly attractive for short-haul (<300m) high-speed interconnections. Besides, Vertical Cavity Surface Emitting Lasers (VCSELs) present interesting performances in comparison to edge-emitting lasers, cost effective and are widely chosen in this type of applications. We aim at achieving an entirely optical fiber Gigabit Ethernet (GbE) link based on 850nm VCSELs to interconnect avionic equipments. To meet IEEE 802.3 standards [1] and ADCN requirements [2], the fiber optic link must be full-duplex, bi-directional, on a single wavelength, and on the same fiber on up to 100m-distance. We have used, at each side of the link, a transceiver module developed for harsh environment applications. Also, there are multiple connections due to production breaks. These connections give birth to return loss (RL) and consequently crosstalk. One might pay attention to the impact of the RL on the link. We present the characterization of a mock-up and the comparison of experimental results with the GbE requirements

Advanced local area network concepts

Development of a good model of the data traffic requirements for Local Area Networks (LANs) onboard the Space Station is the driving problem in this work. A parameterized workload model is under development. An analysis contract has been started specifically to capture the distributed processing requirements for the Space Station and then to develop a top level model to simulate how various processing scenarios can handle the workload and what data communication patterns result. A summary of the Local Area Network Extendsible Simulator 2 Requirements Specification and excerpts from a grant report on the topological design of fiber optic local area networks with application to Expressnet are given

SISTEM NOTIFIKASI DINI KEAMANAN LAND KABEL FIBER OPTIK MELALUI SMS

ABSTRAKSI: Dewasa ini perkembangan teknologi semakin pesat, hal tersebut mendorong terjadinya komunikasi atau pertukaran data dengan jumlah yang besar. Hal tersebut kan mempengaruhi perkembangan jaringan fiber optic yang ada di Indonesia. Fiber optic merupakan salah satu media transmisi dengan kapasitas besar dengan tingkat keandalan yang tinggi. Fiber optic dipasang pada bagian bawah tanah (inland cable) serta bagian bawah laut (submarine cable). Saat ini hampir sebagian besar perusahan baik swasta maupun pemerintah menggunakan teknologi serat optik ini untuk membangun jaringan komunikasinya, terutama untuk jaringan komunikasi data dan biasanya digunakan sebagai tulang punggung (backbone) jaringan mereka. Namun pada implementasinya di lapangan fiber optic bagian bawah tanah rentan terhadap gangguan. Gangguan tersebut dapat berupa pencurian, ataupun gangguan alam yang dapat menyebabkan kabel tersebut putus atau bengkok. Walaupun dalam implementasinya sudah dimonitoring dan dilakukan patrol kabel oleh petugas namun masih dirasa kurang untuk dapat memproteksi kabel fiber optic tersebut. Berdasarkan permasalahan tersebut, pada proyek akhir ini akan dirancang sebuah sistem sederhana yang dapat mengirimkan sms notifikasi yang dapat memberi notifikasi bahwa fiber optic mengalami gangguan. Menggunakan modem gsm sebagai terminal pengirim dan memprogram mikrokontroller agar memerintahkan modem gsm tersebut untuk mengirimkan sms ke nomor petugas patroli kabel fiber optic pada suatu daerah tersebut secara langsungHasil yang diharapkan dari proyek akhir ini adalah suatu sistem yang dapat memberikan suatu notifikasi dini dalam bentuk sms ke nomor penerima apabila kabel fiber optic tersebut terkena gangguan.Kata Kunci : fiber optic, smsABSTRACT: Nowadays more and more rapid technological development, it encourages communication or data exchange with a large amount. It\u27s affected the development of the existing fiber optic network in Indonesia. Fiber optic transmission medium is one with a large capacity with high reliability levels. Fiber optic cables installed in the underground (inland cable) and the bottom of the sea (submarine cable). Currently most of the companies both private and governmental uses fiber optic technology to build communication networks, especially for data communication networks and is usually used as the backbone (backbone) of their networks. But in its implementation in the field of underground fiber optic cables are vulnerable to disruption. The disorder may be a theft, or natural interference that may cause the cable is broken or bent. Although its implementation is monitored and carried out by officers patrol the cable but still felt less able to protect the fiber optic cable.Based on these problems, the final project will be designed a simple system that can send SMS notifications to members know that the fiber optic impaired. Using a gsm modem as a sender and setting up the gsm modem that can send sms to the number of patrol officers on a fiber optic area directly.The result of this final project is a system that can provide an early notification in the form of an sms to the recipient\u27s number when the fiber optic cable is exposed to disturbances.Keyword: fiber optic, sm

Free Space Optical Communications: An Overview

Bridging the so-called “last mile” in communication networks has revived keen interest in free-Space Optics (FSO), also known as fiber-free or fiberless optics, which is a technology that transports data via laser technology. It is a line-of-sight technology that currently enables optical transmission up to 2.5 Gbps of data, voice and video through the air at long distances (4km), allowing optical connectivity without deploying fiber-optic cable or securing spectrum licenses. It is moving closer to being a realistic alternative to laying fiber in access networks. This paper presents an introduction to FSO and the current state of its technology

Development of a dc-ac power conditioner for wind generator by using neural network

This project present of development single phase DC-AC converter for wind generator application. The mathematical model of the wind generator and Artificial Neural Network control for DC-AC converter is derived. The controller is designed to stabilize the output voltage of DC-AC converter. To verify the effectiveness of the proposal controller, both simulation and experimental are developed. The simulation and experimental result show that the amplitude of output voltage of the DC-AC converter can be controlled