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View Full Version : Cell Phones and Wireless Internets should switch from Spread-Spectrumto QAM



Green Xenon [Radium]
04-24-08, 11:55 PM
Hi:

QAM [Quadrature Amplitude Modulation] is superior to spread-spectrum
because the former can sends more bits using less bandwidth than the
later. QAM is is meant to send/receive large amounts of info while
saving bandwidth. Yet so many cell phones and wireless internet routers,
modems, and access points use spread spectrum. Why? It would make a lot
more sense if they switch to QAM, so that wireless internet access can
be faster and cell phones reception can be more efficient. Sure QAM has
more RFI than spread spectrum but it definitely beats the annoying
aliasing you get when using spread-spectrum.

In addition, wireless internets and cell phones should use radio
frequencies that are in or close to the UHF range. UHF is the most
efficient spectrum for radio communications. Last but not least, the
carrier waves should be AM, not FM. FM uses too much bandwidth and cuts
of many other users. AM won't do that. AM's chief drawbacks are the
EMI/RFI resulting from magnetic disruptions, however this only affects
analog reception. QAM is a digital modulation scheme and as such it is
immune to the electromagnetic disturbances that would normally hinder
analog telecommunications.

Any questions/comments welcome.


Thanks,

Radium

DTC
04-25-08, 07:50 AM
Green Xenon [Radium] wrote:
> Any questions/comments welcome.

Bob Myers wrote:
Radium has never actually had an original
question. All of his questions are either rehashing very
well-understood situations, or are utterly nonsensical and
therefore not answerable AS legitimate questions.

RHF wrote:
Since Radium is an ignorant idiot, he has no clue what group would
be appropriate for his moronic questions.

Porgy Tirebiter wrote:
You are a uneducated troll....
You blabber on and on about nothing. No one is interested in your
opinions. Discover women or masturbation, stop playing on Usenet,
we are not amused.

Jim wrote:
Belief doesn't make reality.
A hundred years or so of experments say that's utter, babbling,
nonsense.
I'd suggest fluphenazine and haloperidol.
Babbling, delusional nonsense.
Seek help.
There are drugs that may help your condition if you are treated
early enough.
Radium is a silly-ass, ignorant child.

DTC (that's me) wrote
This thread reminds me of situations where someone acquire a little
knowledge of something and extrapolates it into areas of which they have
a limited skill set for understanding them.


Another example of Radium's mastery of trolldum is:

Radium wrote:
Can the Spin Exchange Relaxation Free Magnetometer
be used to receiver distant AM radio signals in which the
carrier frequency is 150 KHz?

What if the carrier frequency is 44.1 KHz [for the same
reason CDs use a 44.1 KHz sample rate]? 40 KHz?

Thanks a bunch,

Radium

Cubit
04-25-08, 09:19 PM
To say that spread-spectrum uses too much bandwidth makes no sense, since
large numbers of users ocuppy the same band of spectrum at the same time.

Green Xenon [Radium]
04-28-08, 01:26 AM
Cubit wrote:
> To say that spread-spectrum uses too much bandwidth makes no sense, since
> large numbers of users ocuppy the same band of spectrum at the same time.
>
>


Just out of curiosity, if spread-spectrum were transmitted and received
using an UHF-frequency AM-radio wave, what would be the disadvantages?