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SIP Communicator - the Java VoIP and Instant Messaging client.

SIP Communicator is an audio/video Internet phone and instant messenger that supports some of the most popular VoIP and instant messaging protocols such as SIP, Jabber, AIM/ICQ, MSN, Yahoo! Messenger, Bonjour, IRC and a whole lot of other useful features.

SIP Communicator is completely Open Source / Free Software, and is freely available under the terms of the GNU Lesser General Public License.

Near field communication (NFC) is a set of standards for smartphones and similar devices to establish radio communication with each other by touching them together or bringing them into close proximity, usually no more than a few centimetres. Present and anticipated applications include contactless transactions, data exchange, and simplified setup of more complex communications such as Wi-Fi.[1] Communication is also possible between an NFC device and an unpowered NFC chip, called a "tag".[2]

NFC standards cover communications protocols and data exchange formats, and are based on existing radio-frequency identification (RFID) standards including ISO/IEC 14443 and FeliCa.[3] The standards include ISO/IEC 18092[4] and those defined by the NFC Forum, which was founded in 2004 by Nokia, Philips and Sony, and now has more than 160 members. The Forum also promotes NFC and certifies device compliance.[5

CrazyFlie flight video

The copter itself is organised around the main CPU. The job of this CPU is to acquire the physical measurement given by the gyroscopes and accelerometers and to control the motors to keep the copter stable. This is done by a regulation loop which controls the motors speed 250 times per second. The radio communication has a pretty low bandwidth and is used to send commands to the copter and receive telemetry data from it. The CPU program can be updated by radio.

The computer runs control and telemetry programs. The control program reads the input from a game-pad and sends control commands to the copter. We also have programs that can configure the copter regulation parameters and log the measurements in order to make easier to tune the regulation. All the development is done on Windows and Linux. Indeed we are 3 to work on this project, two of us work on Linux and one is mainly on Windows. Using FLOSS permit to handle that in a very effective way. We are mainly using the GCC compiler from CodeSourcery for the copter program compilation, GNU Make for the project build, Mercurial for the source control, and python/pyusb for the communication with the copter. All these softwares works seamlessly on both Linux and Windows and made the project pretty easy to handle. The distance between the motors (horizontally and vertically) is around 8 cm and the total weight is around 20 g.

Public switched telephone network

is the network of the world's public circuit-switched telephone networks. It is a worldwide network of telephone lines, fiberoptic cables, microwave transmission links, cellular networks, communications satellites, and undersea telephone cables connected by switching centers, which allows any telephone in the world to communicate with any other. Originally a network of fixed-line analog telephone systems, the PSTN is now almost entirely digital in its core and includes mobile as well as fixed telephones.

(PSTN)

Overview

Tor is a network of virtual tunnels that allows people and groups to improve their privacy and security on the Internet. It also enables software developers to create new communication tools with built-in privacy features. Tor provides the foundation for a range of applications that allow organizations and individuals to share information over public networks without compromising their privacy. Individuals use Tor to keep websites from tracking them and their family members, or to connect to news sites, instant messaging services, or the like when these are blocked by their local Internet providers. Tor's hidden services let users publish web sites and other services without needing to reveal the location of the site. Individuals also use Tor for socially sensitive communication: chat rooms and web forums for rape and abuse survivors, or people with illnesses.

Le LTE (Long Term Evolution) est l'évolution la plus récente des normes de téléphonie mobile : GSM/EDGE, UMTS, CDMA2000 et TD-SCDMA.

La largeur de la bande de fréquences allouée à l’opérateur du réseau. Le débit utile est pratiquement proportionnel à cette largeur de bande (pouvant varier de 1,4 MHz à 20 MHz en LTE, 100 MHz en LTE Advanced).

Les types d’antennes utilisés coté terminal et coté réseau (antenne relais): le débit binaire maximal de 326,4 Mbit/s suppose des antennes MIMO 4X4 (quadruples) aux 2 extrémités de la liaison radio LTE (cas de figure peu réaliste pour un téléphone mobile ou un smartphone). La distance entre le terminal et la (ou les) antennes fixes (le débit est très inférieur en périphérie de cellules radio à cause des interférences avec les cellules adjacentes) et les conditions de réception radio (interférences, bruit, échos liés aux réflexions sur les immeubles, …). Le nombre d’utilisateurs actifs se partageant la bande passante au sein d’une cellule (surface radiante d'une antenne) LTE; plus il y a d’abonnés en communication moins chacun a de débit unitaire. La position fixe (statique) ou « en mouvement » du terminal de l’abonné ; le débit utile est réduit pour un terminal en mouvement. La capacité en débit et en nombre d'utilisateurs simultanés de la station de base (eNode B) et le débit du lien optique reliant cette station au cœur de réseau. Le type et la catégorie du terminal influent aussi sur le débit maximum possible ; par exemple un terminal LTE (en anglais : UE "User Equipment") de catégorie 1, ne supporte qu’un débit binaire de 10 Mbit/s alors qu’un autre de catégorie 3 supportera 100 Mbit/s (voir tableau ci-dessous). En contrepartie, plus la catégorie du terminal est élevée, plus le terminal sera complexe (coûteux) et moins son autonomie sera grande (à niveau technologique égal).

Hackerspaces

Hackerspaces are community-operated physical places, where people can meet and work on their projects. This website is for 'Anyone and Everyone',who wants to share their hackerspace with international hacker's'paces.

Unlicensed Mobile Access ou UMA est une technique qui a pour objectif de remplacer la couche physique des réseaux GSM et GPRS par des bandes de fréquences libres d'utilisation, celles des 2,4 GHz, ou l'on trouve Bluetooth et Wi-Fi entre autres. Elle a été développée par un consortium d'entreprises nommé UMAC comptant entre autres Alcatel, Cingular, Ericsson, Motorola, Nokia, Nortel, Siemens, T-Mobile et Kineto Wireless. L'objectif ultime de l'UMA est de faire converger les protocoles de communications des téléphones mobiles, fixe et informatiques.

Socket Communications CompactFlash RFID Reader Card 6E ( RF5400-542 )

Product Details Integrated Type II CF card plugs into the Type II CompactFlash slot of Windows Powered Pocket PCs Reads and writes to ICode 1, Tag-It HF and PicoTag proprietary HF tags Reads and writes to the most popular HF ISO 15693 tags, including ICode SLI/SL2, LRI512, my-d and Tag-It HF-I High frequency, 13.56MHz reader/writer Add plug-in RFID capabilities to Pocket PC applications

$186.60

So NFC is just a method of communication between two devices at short distance. What makes the NFC antenna design simple or easy? If you know much about antennas, the first question you might ask is what is the operating frequency of NFC. It turns out that these devices operate around 13.56 MHz. The corresponding wavelength is 22 meters long - this means to get a nice half-wave dipole antenna (that radiates well) we would need a device about 11 meters in length.

he NFC antenna area may be limited to 3"x1" (or 7 cm * 2.5 cm). Hence, we are talking about fitting an antenna i

to a volume where the maximum linear dimension is about 0.5% or less of a wavelength. And from antenna theo

Z-Wave is a wireless communications protocol designed for home automation, specifically to remotely control applications in residential and light commercial environments. The technology uses a low-power RF radio embedded or retrofitted into home electronics devices and systems, such as lighting, home access control, entertainment systems and household appliances.

Light-emitting diode

A light-emitting diode (LED) is a semiconductor light source.[3] LEDs are used as indicator lamps in many devices and are increasingly used for other lighting. Introduced as a practical electronic component in 1962,[4] early LEDs emitted low-intensity red light, but modern versions are available across the visible, ultraviolet, and infrared wavelengths, with very high brightness. When a light-emitting diode is forward-biased (switched on), electrons are able to recombine with electron holes within the device, releasing energy in the form of photons. This effect is called electroluminescence and the color of the light (corresponding to the energy of the photon) is determined by the energy gap of the semiconductor. LEDs are often small in area (less than 1 mm2), and integrated optical components may be used to shape its radiation pattern.[5] LEDs present many advantages over incandescent light sources including lower energy consumption, longer lifetime, improved robustness, smaller size, and faster switching. LEDs powerful enough for room lighting are relatively expensive and require more precise current and heat management than compact fluorescent lamp sources of comparable output. Light-emitting diodes are used in applications as diverse as aviation lighting, automotive lighting, advertising, general lighting, and traffic signals. LEDs have allowed new text, video displays, live video, and sensors to be developed, while their high switching rates are also useful in advanced communications technology. Infrared LEDs are also used in the remote control units of many commercial products including televisions, DVD players, and other domestic appliances.

3D Printing with Sculptris

Sculptris is a supercool free sculpting tool. You can download it here from Pixologic. Much like ZBrush, Sculptris is a solid-body sculpting tool. Since it has an export function, we can use it for 3D printing too! Unfortunately at this stage we don't yet support OBJ files, so there's a couple of easy hoops you need to jump through to get your design ready. First export your sculpt as an OBJ file:

1.1 Cryptography is Dangerous (and Beautiful)

2 Basics first

3 PGP / GPG

Japan collab transmits record data speeds on terahertz waves

Researchers from Japan-based semiconductor manufacturer Rohm, together with a team from Osaka University, have come up with a chip that, in experiments, has achieved a wireless data transmission speed of 1.5 gigabits per second. This is a record breaker as the world's first terahertz wireless communication achieved with a small semiconductor device. The chip’s ability to transmit at such a quick speed is not the end of the story. Even higher transmission speeds of up to 30 Gbps may be possible in the future, according to reports.

“Research into terahertz technology utilising Terahertz frequency (100GHz-10THz) is now receiving increasing attention around the world,” according to an Osaka University publication

USB On-The-Go and Embedded Host Virtually every portable device now uses USB for PC connectivity. As these products increase in popularity, there is a growing need for them to communicate both with USB peripherals and directly with each other when a PC is not available. There is also an increase in the number of other, non-PC hosts (Embedded Hosts) which support USB in order to connect to USB peripherals.

Fonctionnalités spécifiques à Google Earth Pro Données démographiques Importation et définition du style des données Exportation et présentation des données Outils de mesure avancés Marquage, enregistrement et partage de lieux Marquage et enregistrement de lieux Organisation des lieux Modification et personnalisation de lieux Importation de vos données Utilisation de périphériques GPS Utilisation des superpositions d'image Importation de données vectorielles Utilisation d'autres types de données Utilisation des modèles Utilisation des données KML À propos des projections et des plans de référence Création de vidéos et visites de lieux Tours Movies Partage d’informations sur un lieu Partage de contenu Envoi d'une image par e-mail Envoi de données de lieu par e-mail Submitting to the Google Earth Community Partage de données sur un réseau Hosting KML Content Résolution des problèmes d'e-mail

Extensible Messaging and Presence Protocol

Extensible Messaging and Presence Protocol (qu'on peut traduire par « protocole extensible de présence et de messagerie »), souvent abrégé en XMPP, est un ensemble de protocoles standards ouverts de l’Internet Engineering Task Force (IETF) pour la messagerie instantanée, et plus généralement une architecture décentralisée d’échange de données. XMPP est également un système de collaboration en quasi-temps-réel et d’échange multimédia via le protocole Jingle, dont la Voix sur réseau IP (téléphonie sur Internet), la visioconférence et l’échange de fichiers sont des exemples d’applications.