Re: TI-H: hey (cont.)
[Prev][Next][Index][Thread]
Re: TI-H: hey (cont.)
they use coloured light in the phone line fiber optic system here...
Olle Hedman wrote:
> Sassamo16@aol.com wrote:
> > i also had a similar idea with different colors, although slightly different
> > instead of red=1, blue=2, green=3, etc., it would be
> > red=0, blue=1, green=10, orange=11, etc.
> > the would only be helpful in data transfer though, not data storage
>
> different colors is behaveing differently in the same medium. The reson they
> have choosen the color they have is that that color is tranfered with the least
> loss at an affordable price of the light generator.
> To have differnt colors in the same fibre would raise a lot of problems. one is
> the transmitting device. blue is very hard and expensive to make for example.
> another one is the resciver. As for now, you only have to detect light or no
> light. That is MUCH easier than detect different colors.
> something close to your idea is actually used in modern modems, that send
> several bits per baud, by modulateing both phase and amplitude.
> as for today, your technique would be far to expensive and bulky. apart from the
> problem with different signal loss of the different colors.
> maybe in the future.
References: