Why don't you modulate each pair with different carrier? Also I think you have to play with the power that Tx LEDs will emit.
Ioannis
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Why don't you modulate each pair with different carrier? Also I think you have to play with the power that Tx LEDs will emit.
Ioannis
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That's a better description of what I was trying to say.Originally Posted by Ioannis
Wisdom is knowing what path to take next... Integrity is taking it.
Ryan Miller
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I think I smell what you're cooking. I saw it on one of those shows talking about Ford Motor Company's assemblies processes.
How big are the boxes themselves?
How many are there going to be?
Last edited by skimask; - 25th April 2007 at 18:35. Reason: Changed BIGS to BOXES (don't know what I was typing there!)
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Sorry, I don't understand your comments...
What's a carrier?
Why working on the LED's power?
What are the bigs?
Roger
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Carrier = Porteuse (ou fréquence porteuse)
Roughly, it's the frequency you modulate your signal. like an FM/AM radio station.
Why playing with the Power of the LED... more power (current) = usually better range, lower power, lower range.
Last edited by mister_e; - 25th April 2007 at 18:50.
Steve
It's not a bug, it's a random feature.
There's no problem, only learning opportunities.
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Carrier - the underlying information mode of transport. For instance...air is the carrier for sound waves, we modulate the air when we speak. Like AM radio, 900khz is the carrier, which we modulate the amplitude of to get the audio information from. Make any sense?
With an IR LED, the way it's most commonly done is to modulate the IR LED with a ~38Khz signal, then turn that whole signal on/off and a certain rate.
If you've got one IR LED working at 38khz and another one next to it working at say 50khz, the two probably won't interfere with each other as opposed to having two of them modulated at the same frequency next to each other.
A good example would be you and wife going out with another husband/wife couple. Both him and his wife are talking at the same time, both are transmitting different modulated carrier waves (sound), but you're only tuned into him, and that's easy (maybe 'cause it's easier for the guys to tune out the girls sometimes!...oh that's gonna start something I can feel it now!
). If you were in that same situation talking to 3 other guys (with similar voices), it would be a lot harder to figure out who's talking to who.
Power - maybe because some of the light might spill over to other IR detectors...
Bigs - fixed it...should have read 'How big are the boxes themselves?'
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Yep... probably the same system. The approach that Skimask suggests would do the trick. If you stagger the frequency to say every other emitter/reciever pair that are next to each other, you effectively reduce the possibility of picking up a stray signal from an adjacent pair. The other thing is to look into some kind of filter lens or plastic that will filter out stray IR similar to what you see on you VCR/DVD IR receiver.
Wisdom is knowing what path to take next... Integrity is taking it.
Ryan Miller
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i'll second that one. i'll read back the whole thing but i think some sequential scanning & Beaming may help too...
Steve
It's not a bug, it's a random feature.
There's no problem, only learning opportunities.
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Okay for all your infos.
I think I'm going to start with IR and make some tests.
Just found an old remote where I can recover an IR-LED...
Roger
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Also you may switch off the pairs and have on only one at a time. Of course this has to be done fast enough. Like scanning a keyboard. I suppose that is what Steve implied?
Ioannis
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