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One-Watt Wireless Radio Modem Reaches 40 Miles
maxstreampr wrote in to plug their
radio modem. It's the size of a credit card, one watt, and can transmit 40 miles line of sight or 3000 feet indoors. Something about using the AT command set to fire off a command 40 miles through the air amuses me.
+++ATH0 on a cloudy day. With a repeater.
If everyone bought one of these and ran them in peer-to-peer mode, we could all dump our ISPs!
If someone says he and his monkey have nothing to hide, they almost certainly do.
Additionally, rumor has it that this device will burn a hole in your pocket. (Thank you, I'm here all week.)
Do you like German cars?
"Site" - a location.
"Sight" - something visual.
"Line of sight" - a line along which you can see (i.e., an unobstructed line.)
"Line of site" - evidence that what you've written matters so little to you that it's not worth the effort to proofread. You don't care; why should we?
The Advanced Encryption Standard (AES) is used with a 256-bit key, the highest encryption standard available.
The real question is, did they use Lexar programming techniques?
Using the AT command to set a fire 40 miles off? Or has it just been too long a day at work? My office has been regularly swept for mines.
I submitted this story last night, and it didn't get posted.
What kind of antenna did they use? "High gain" isn't all that descriptive.
-Randy
Do you mean PCMCIA-sized?
The speeds indicated look too slow to be useful except for remote low overhead / slow data acquisition stuff.
9600 baud is pretty darn slow, even with compresion.
Agent K: A *person* is smart. People are dumb, stupid, panicky animals, and you know it.
Apparently, the editors are hedging their bets on this one: I keep hitting reload, and the submission text alternates between "line of sight" to "line of site".
Wow, that's some marketing. The "40 miles" claim is when you're in deep space and using high gain antennas. Actual performance will be less than a mile. Also, in case people want to compare this with 802.11 (which is difficult because they are in different bands), a typical 802.11b card radiates 30mW, instead of the 1W these guys are apparently claiming. The data rate is nothing exceptional either, 115.2kbps (and these are 1000 bits/kb sized), which pales in comparison to 802.11g at ~55000kbps. This technology would have a much higher "wow" factor 5 years ago, but nowadays that kind of range for that kind of throughput just isn't all that new or special.
I read the internet for the articles.
Dilbert: okay.
Mordac: What?! No engineer gives up email so easily. Assume the position!
Dilbert (at home, to Dogbert): So, he found the modem strapped to my ankle, but he missed my wireless pen modem.
"A witty saying proves nothing." ~Voltaire
"d'Oh!" ~Homer
Our radiolinks (which are like wi-fi) were sending line-of-sight transmissions, 9600 baud, with about 3 milliwatts. I cannot remember the frequencies we used but they were in the microwave range so I'm not sure it's comparable with the radiomodems mentioned in the article using 900 MHz band. Cool stuff anyway!
No time penalty is incurred during AES encryption or decryption.
That's pretty interesting. Perhaps they meant to say that there is no additional processing overhead beyond that which is introduced by performing the full number of rounds for a 256 bit key in hardware.
It seems you still need a shared secret. I assume it isn't doing any authenticated Diffie-Hellman to establish a session key.
Sorry, it's just kind of irritating when you hear things like "security through encryption." Great. You get integrity protection and data confidentialy while the data is in trasit. There are many other opportunities for an attacker to get your data besides when it's flying around in mid-air.
I bootleg Fizzy Lifting Drinks.
Although 9600 could never handle today's internet and web activities, it is amazingly fast for TTY and CLI type applications. Having started with 110 baud mechanical TTY and 300 baud acoustical coupler modem on a green screen, I well remember my first experience with a 9600 baud hardwired Lear Siegler terminals -- WOW very fast.
9600 baud is good enough for modem-to-modem chat, e-mail via pine, text processing with vi or emacs, or almost any *nix command. Thinking about this reminds me of how terribly bloated everything has become with verbose formatting and styling of pages. Pictures may be worth a 1000 words, but they require 10 to 100 times the bandwidth of those words.
Two wrongs don't make a right, but three lefts do.
A: If they say, "Something about using the AT command set to fire off a command 40 miles through the air amuses me."
Great ideas often receive violent opposition from mediocre minds. - Albert Einstein
In ham radio, there's a 1000 miles per watt award that's not particularly hard to get....I made 1842 miles per watt (Palo Alto, California to Sakhalin Island in Russia) using a data modulation called PSK-31 and a wire antenna on my roof, and just over 1000 miles per watt from San Luis Obispo, CA to Estonia using CW: 5700 miles with 4.5 watts to a 28 foot wire thrown from a second-story window into a small tree, running on a pack of AA batteries.