اتحاد بيانات الآشعة تحت الحمراء

IrDA logo

Infrared via USB

اتحاد بيانات الآشعة تحت الحمراء (Infrared Data Association ؛ IrDA) هي جماعة مصالح منتجين تأسست في 1993 من نحو50 شركة. IrDA provides specifications for a complete set of protocols for wireless infrared communications, and the name "IrDA" also refers to that set of protocols. The main reason for using the IrDA protocols had been wireless data transfer over the "last one meter" using point-and-shoot principles. Thus, it has been implemented in portable devices such as mobile telephones, laptops, cameras, printers, and medical devices. Main characteristics of this kind of wireless optical communication is physically secure data transfer, line-of-sight (LOS) and very low bit error rate (BER) that makes it very efficient.

المواصفات

IrDA protocol stack

IrPHY

The mandatory IrPHY (Infrared Physical Layer Specification) is the physical layer of the IrDA specifications. It comprises optical link definitions, modulation, coding, cyclic redundancy check (CRC) and the framer. Different data rates use different modulation/coding schemes:

SIR: 9.6–115.2 kbit/s, asynchronous, RZI, UART-like, 3/16 pulse
MIR: 0.576–1.152 Mbit/s, RZI, 1/4 pulse, HDLC bit stuffing
FIR: أربعة Mbit/s, 4PPM
VFIR: 16 Mbit/s, NRZ, HHH(1,13)
UFIR: 96 Mbit/s, NRZI, 8b/10b
GigaIR: 512 Mbit/s – 1 Gbit/s, NRZI, 2-ASK, 4-ASK, 8b/10b

سمات أخرى:

المدى:
- standard: 1 m;
- low-power to low-power: 0.2 m;
- standard to low-power: 0.3 m.
- Theعشرة GigaIR also define new usage models that supports higher link distances up to several meters.
Angle: minimum cone ±15°
Speed: 2.4 kbit/s to 1 Gbit/s
Modulation: baseband, no carrier
Infrared window (part of the device body transparent to infrared light beam)
Wavelength: 850–900 nm