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Jac Londe

Near field communication - Wikipedia, the free encyclopedia - 0 views

  • 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
Jac Londe

Daedalus Projects - 0 views

  • 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.
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  • The top of the board contains the sensors and the control/communication electronic: The JTAG/Serial connector permit to program the processor and to communicate debug messages. The Main CPU is a STM32 Cortex-M3. It is clocked at 64MHz from the internal oscillator. The 2 Axis X-Y Gyro is an invensense IDG500. It has an analog output and thus is connected to the CPU analog to digital converters. The 1 Axis Z gyro is an invensense ISZ500. As the X-Y gyro this is an analog chip connected to the CPU analog to digital converters. The 2.4GHz Radio is based on a nRF24L01+ chip from Nordic Semiconductor. It is actually a breakout board sold by SparkFun. The Radio is connected to the CPU via a SPI port. The 3 Axis Accelerometer is a SMB380 from Bosch. It is connected to the CPU via an I²C bus.
  • Here nothing particular, except that the little battery is taped on the bottom of the copter. The battery comes from a Silverlit x-twin plane and actually permit 4.5min of flight time.
  • Under the battery we mostly have power supply and the “power” electronics: The charge connector accepts 5V and permits to charge the battery The power switch permits to power the copter either from the charge connector or from the battery. The 5V step-up permits to increase the power voltage from the 3~4V coming from the battery to 5V. The two 3.3V linear regulators, reduces the 5V to power the copter electronic. The digital and analog 3.3V are generated independently. This was made to reduce the noise on the analog components (here it is the two gyros, a quite critical part). Finally at the four sides we have the motors transistors. The power for the motors pass on the top and bottom of the part of PCB that hold the motors. It can be noted that we also have the battery charging chip just at the right of the 3.3V regulators. It is a classical MAX1555 and is working pretty well. The idea with the step-up was to get a more stable voltage when the battery is depleted and also to remove some of the noise coming from the motor electonic. Anyway, this boars is capable to work without by using 2.8V linear regulators instead. So most likely the step-up will be excluded on the next version and we also plan to integrate the radio on board. The motors and propellers are taken from a Silverlit X-twin plane. They are powered by the battery voltage.
  • The copter is controlled via a python program running on the PC. A Playstation bluetooth gamepad is used to pilote it.
Jac Londe

Grundig G2 Reporter | The Eton Webstore - 0 views

  • Grundig G2 Reporter
  • AM-FM-SW-Radio/Recorder Features Digital AM/FM/SW Radio with Signal Strength Indicator 248-station Memory Storage 5 Tuning Methods: Jog Tuning, Manual, Auto Tuning, Memory, ATS (Auto Tuning Storage) MP3 and WMA Decode and Recording, E-Book TXT Support Dual Stereo Speakers with Digital Volume Control Record Functions: MIC Record, Line-in Record, Record Radio (able to record while playing) Sleep Timer and Alarm Clock Functions Multiple Language Selection Built-in Flash Memory (4GB) Built-in micro-SD Card Reader (supports up to 16GB) Upgradable Firmware Ports: 3.5mm headphone output, Line-In, MIC, MINI-USB 2.0 Jack (High Speed) Rechargeable Lithium Battery (1250mAh), Charge Through USB Dimensions: 7½" W x 3½" H x 0.8" D (190 x 90 x 21 mm) Weight: 9.6 oz. (272 g)
Jac Londe

LTE (réseaux mobiles) - Wikipédia - 0 views

  • 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).
Jac Londe

USS Lincoln VS canada - 0 views

  • USS Lincoln VS canada This is the translation of the ACTUAL radio conversation of a U.S. naval ship with the Canadian authorities off the coast of Newfoundland. The Chief of Naval Operations on October 10th 1995 released the radio conversation. Canadians: Please divert your course 15 degrees to the South to avoid a collision. Americans: Recommend you divert your course 15 degrees to the North. Canadians: Negative. You will have to divert your course 15 degrees to the South to avoid a collision. Americans: This is the Captain of a US Navy ship. I say again, divert YOUR course. Canadians: No. I say again, you divert YOUR course. Americans: THIS IS THE AIRCRAFT CARRIER USS LINCOLN. THE SECOND LARGEST SHIP IN THE UNITED STATES ATLANTIC FLEET. THREE DESTROYERS, THREE CRUISERS AND NUMEROUS SUPPORT VESSELS ACCOMPANY US. I DEMAND THAT YOU CHANGE YOUR COURSE 15 DEGREES NORTH, I SAY AGAIN, THAT'S ONE FIVE DEGREES NORTH, OR COUNTERMEASURES WILL BE UNDERTAKEN TO ENSURE THE SAFETY OF THIS SHIP. Canadians: We are a lighthouse. Your call.
Jac Londe

Z-Wave - Wikipedia, the free encyclopedia - 0 views

  • 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.
Jac Londe

CX-01 mini flash androïde de non-et d'ICS Telechips 8923 1.0GHz 512MB 4GB de l'androïde 4.0 de boîtier de protection de bâton du PC HDMI - french.alibaba.com - 0 views

  • Système d'opération : Androïde 4.0 ICS de GoogleConnexion internet de Wi-FiHDMI dehors 1080PAppui de l'instantané 11 d'AdobeCortex A5 Processor+Mali400 GPU de Telechips TCC8923 1.0GHzMarché androïde, milliers d'apps disponiblesContrôleur/infra à télécommande à distanceYouTube, Hulu, radio d'Internet, jeu visuel en ligne etc. Facebook, Twitter, Picasa, clignotement, gestion de réseau de Social de Google+ etc. Gmail, lecteur de pdf, bureau de lecteur d'e-Livre à allerSoutient la langue multi : Arabe, anglais, français, italien, allemand, espagnol, portugais, grec, hollandais, danois,Le Russe, polonais, Norvégien, Suédois, Tchèque, turc, a simplifié/chinois traditionnel, Coréen, et Japonais
Jac Londe

Asus Padfone Unlocked Available (Full Specifications) - 0 views

  • ASUS lifted the veil over its long-awaited redesigned 9.2mm thin PadFone at the MWC. Sporting a 4.3-inch Super AMOLED qHD display, Snapdragon S4 with the new Adreno 225 GPU, and 8MP camera with LED flash and f/2.2 aperture, as well as 16-64GB of internal storage plus microSD slot, it has what we would expect from a modern high-end. Connectivity is taken care of 42Mbps HSPA+ radio, Wi-Fi, Bluetooth 4.0, HDMI and A-GPS, while a 1,520mAh battery unit is included as a juicer. The Padfone can get inserted into an optional tablet frame, whose 10.1 inch screen then gets powered by the phone itself, and can extend your battery life significantly. There is another dock, which allows you to add a detachable keyboard accessory, like on the Transformer Pad series. This one also comes with a stylus that except for doodling can be used to receive your phone calls as well, considering that the phone is inserted in the mothership.
Jac Londe

Arduino playground - Resources - 0 views

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