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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

2MP Auto Focus mini Board Camera

2MP Auto Focus mini Board Camera 1. 2MP 2. Autofocus Board Camera 3. USB interface Model NameUM2CU  2MP Auto Focus Board CameraInterfaceUSB CMOS CameraResolution 2.0MegapixelFocus Type AutofocusUVC YesMicrophoneNoEffective Distance6 cm to infinityF No.F 2.8View Angle58.5 ( FOV )Frame Rate30 fpsDimension38.0mm(L) X 9.8mm(W) X6.55mm(H)OS SupportedWindows XP, Vista, Windows 7,                          Linux Kernel 2.6                MAC OS 10 or above

Specifications

VGA 0.3 Megapixel Camera Module

Specifications VGA 0.3Megapixels Camera Module Model NameUM72U VGA 0.3Megapixels Camera ModuleInterfaceUSB CMOS CameraResolutionVGAFocus TypeFixfocusUVCYesMicrophoneNoEffective Distance30 cm to infinityF No.F 2.8View Angle67° ( FOV )Frame Rate30 fpsDimension43.0mm(L) * 9.0mm7.5(W) *4.5mm(H)OS SupportedWindows XP, Vista, Windows 7,                                                                                           Linux Kernel 2.6                                                                                           MAC OS 10 or above

Metre From Wikipedia, the free encyclopedia   (Redirected from Meter) Jump to: navigation, search This article is about the unit of length. For other uses of "metre" or "meter", see meter (disambiguation). 1 metre = SI units 100 cm 1000 mm US customary / Imperial units 3.2808 ft 39.370 in The metre (meter in the US), symbol m, is the base unit of length in the International System of Units (SI). Originally intended to be one ten-millionth of the distance from the Earth's equator to the North Pole (at sea level), its definition has been periodically refined to reflect growing knowledge of metrology. Since 1983, it has been defined as "the length of the path travelled by light in vacuum during a time interval of 1 ⁄ 299,792,458 of a second.[1]

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.