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Radio Frequency communications vs. Infra Red communications

I'm having trouble finding examples of devices that use radio frequency technology and those that use infrared (IR which includes the IrDA specifications IrPHY, IrLAP, IrLMP, IrCOMM, Tiny TP, IrOBEX, IrLAN and IrFM "Point & Pay"). And I also could use help recommending at least two IR devices and two 802.11 devices to be used in the design of the WLAN of a local hospital. Please compare costs and capabilities of each device. This would be a great help to me.
Thank You

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About RF and IRA
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The primary IEEE 802.11 standards in use today are 802.11a and 802.11b, which both use radio waves for transferring information wirelessly over a network.

The 802.11 standard also includes the 802.11 Infrared (IR) Physical Layer. 802.11 IR defines 1Mbps and 2Mbps operation by bouncing light off ceilings and walls to provide connectivity within a room or small office. This infrared version of the standard has been available since the initial release of the 802.11 standard in 1997.

The reason that 802.11 IR is unheard of is that there are no known vendors that sell products compliant with 802.11 IR. Some offer infrared-based wireless LANs that come close to the standard. For example Spectrix, once the chair of the 802.11 IR group, offers wireless LAN products that implement diffused optical technologies very similar to 802.11 IR.

There have not been any updates to the 802.11 IR standard in order to successfully compete with the higher performing 802.11a and 802.11b. With only 2Mbps data rates, most IT organizations opt for radio-based solutions instead. As a result, 802.11 is known primarily as a radio-based technology.

The primary difference between infrared and radio wireless LANs is the frequency of the transmitted signal. 802.11a and 802.11b operate in the 2.4 and 5GHz bands respectively, but infrared systems use frequencies in the terahertz range. This places infrared signals in the light region invisible to the human eye and beyond the control of the Federal Communications Commission (FCC).

Because of the extremely high frequency, infrared light is highly reflective, which makes it behave like an incandescent light bulb. Each client station (e.g., laptop or PC) is equipped ...

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