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18 Mile Bluetooth? Really? Eh, no.
August 03, 2007
From the department of "Really? You can do that????" comes the announcement of an 18 Mile range Bluetooth dongle!!
Apparently, "when installed professionally", the Aircable Host XR has a range of up to 18 miles!!
Good Lord! That means I could (for example), listen to music on my home PC from anywhere around Dublin on my Moto Rokr headphones.
When I read this I thought "yeah, bet they cost $1,000, sheesh!". Nope - $129. However, I then thought the antenna must cost a fortune (the ones they come with have a range of up to a mile). Nope - they're not too pricy either.
So what's the catch?
Well - the devil is in the detail. From the Wireless Cables Website FAQ:
Generally speaking we give range figures using 2 XR devices (AIRcable Host XR or AIRcable Industrial XR) with the same antenna talking to each other outdoors in a line of sight environment and in beautiful Santa Cruz weather, for example: on the beach.The standard range you can expect with the included antenna is about 1km range. The largest rubber duck antenna (9dBi) gives you 2km range. This is about the limit of the FCC certification for omni-directional antennas. Using directional antennas we can reach a range of about 10km within the FCC regulations using two 18dBi directional antennas.
If you use one XR and one other device with a weaker radio you get less range. With a cell phone or PDA you can expect about 100m range depending on the antenna. With a good directional antenna you get about 1km range maybe more communicating with a cell phone.
Bluetooth headsets attached to your ear will have a more limited range. Bluetooth radio waves do not pass through your head, and in fact don't even get through the outer layers of the skin. If you turn your head so that your head is between the antennas, your head will reduce the range.
Stereo Bluetooth headsets are better since right and left ears are connected, which helps the reception even if the antenna is only on one of the ear muffs.
Anything between the transmitters will reduce signal strength. A wall will reduce the range. The range reductions will depend on the wall's material and thickness.
Bluetooth radio waves bounce off walls too. A staircase between stories allows the signal to go from one level to another, even in a steel reinforce concrete building.
OK, fair enough. I think this means that, unless I find a way to attach a directional antenna to my ROKR headphones, and point myself at my house from somewhere in Dublin, ideally with no walls in between me and my house, it aint' gonna work.
Pity. I'll just have to keep doing it the old way
Comments
Yeah, I also got excited when I heard that Aircable Industrial XR transmits data up to 28 miles! But unfortunately, it can reach this range when both sides use Industrial XR with 24 dBi directional antennas.
The pitiest part is I bought the Industrial XR to exchange data with my cell phone, but Industrial XR doesn't come with necessary software which can easily allow you to exchange data between two devices like any other ordinary Class 1 bluetooth dongles do. I was told I need to install a special program to my cell phone to do so. If you select some music file in your cell phone and try to send it through bluetooth in your cell phone, it won't work. Industrial XR uses a Serial Port Profile to exchange data and ordinary file transfer from cell phone through using its bluetooth cannot perform the thing you want to do.