'Twisted' waves could boost capacity of wi-fi and TV

[Notebook]

http://www.bbc.co.uk/news/science-environment-17221490

Not sure if this is a new method of modulation or a variant on Phase/FSK?

[ame="http://en.wikipedia.org/wiki/Phase_modulation"]Phase modulation - Wikipedia, the free encyclopedia[/ame]
http://en.wikipedia.org/wiki/Frequency-shift_keying

Either way, looks like more telly coming your wave.

N.

 

[n72.75]

Hmm?

This doesn't fit with my understanding of physics.

That's likely my fault, though.

 

[Izack]

Heard about PM ages ago, IIRC on this forum. Took them long enough. :lol:

 

[tblaxland]

It sounds to me like they are encoding the signals on channels with differing amounts of [ame="http://en.wikipedia.org/wiki/Circular_polarization"]circular polarisation[/ame].

Satellite PayTV operators already regularly use a 90 degree linear polarisation separation (in conjunction with other encoding schemes, such as nPSK) and I'm not sure if circular polarisation is any better or not. One problem with linear polarisation is that it can suffer badly from crosstalk between channels as the polarisation is quite susceptible to changes in atmospheric conditions. Maybe circular polarisation offers some greater immunity in that regard, or perhaps it has lower bit error rates at lower polarisation separations.