On 8/3/07, pinniped <[EMAIL PROTECTED]> wrote: > > (quote) > Bluetooth uses the same frequency range as 802.11b and g ... > (end quote) > > That's right, and you're also right about the power meant to be limited to > less than a "normal" 802.11 transceiver. I've mostly seen Bluetooth run as > an extra protocol on top of 802.11b/g and thus no extra gizmos and no reduced > power limit; the USB Bluetooth gizmos do have the power output limited and > these specialized gizmos were pretty much a waste of money. All in all I > never had a use for Bluetooth - I always saw it as a nice way to cripple your > otherwise OK 802.11 network. There is absolutely nothing in the Bluetooth > protocol spec that hadn't already been accomplished by other tools, in many > cases over a decade before (so much for the "future" hype). Now "Zigbee" is > being touted as a "Bluetooth killer" - what is it? Why, lower-power 802.11. > Sound familiar? Wasn't that Bluetooth? Yet more hype. However, Zigbee *may* > have a use in inherently very-low power gizmos with very short range - for > example tracking devices in laptops to determine where they are in a > building. I'm sure people can think of more sensible applications; I just > have none of my own. > > Going back to the original post, as for comments like "you absolutely must be > able to see the antenna", they are generally made by people who don't really > know what they're talking about. There's a hell of a lot of nonsense on the > internet. (I'm sure I contribute to that on occasion). But the original quote > gives me the impression that the author is talking about getting a signal in > a "public park" in which case he's pretty much right - the frequency used by > 802.11 will be severely attenuated by a tree so in *many* cases if you can't > see the antenna, you probably won't get a signal. In reality you get > "multipaths" or the antenna may be behind some object which doesn't block > much of the signal and you manage to get a wireless signal after all - all in > all, just switch on that laptop and see what happens and in general ignore > the "thou shalt not" statements. > > > -- > To UNSUBSCRIBE, email to [EMAIL PROTECTED] > with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED] > >
For what it is worth, here is my experience with wireless through walls. I have a wireless router (WRT 54G) that is my access point for a DSL connection in the house, and a remote Linux box in another building about 50 feet away from the WRT 54G. The signal from the router in the house has to pass through a very thick well insulated wood frame wall, and through another thick wood frame wall on its way to the remote wireless card. There are some windows in the walls, but there is no line of sight path, and no significant metal in the walls aside from normal wiring services. I found that the remote card did report many repeated packets due to losses, so I looked into replacing the supplied "ducky" type antenna with something better. I found that a directional antenna at the remote end (on the wireless card) dramatically helped. I built my own antenna (Google "tin can antenna"). I still get some lost packets on receive, but not many. Dave W.
