TELECOM Digest OnLine - Sorted: Re: Nokia 6010 Reporting in to Mama -- Radio Interference?

Re: Nokia 6010 Reporting in to Mama -- Radio Interference?

Michael D. Sullivan (userid@camsul.example.invalid)
Mon, 07 Mar 2005 04:46:41 GMT

In article <>, says:

>> True. I was told by a contact at ETSI (the organisation that defined
>> many of the GSM standards) that this was originally an oversight --
>> they had not realised that the modulation scheme was effectively 100%
>> amplitude modulation, which would be "detected" by any rectifying
>> circuit nearby. It caused a lot of consternation in the early days.

>> The "solution" they eventually agreed was to reduce the power
>> transmitted by the phones by a factor of 10. This had been proposed
>> anyway, to reduce the cell size and hence increase system capacity
>> (also to increase battery life).

> So GSM that we have today is a patch on top a patch. Nice to think about
> that.

But the 3G migration path for GSM is UMTS, also known as W-CDMA. It
does not use time division multiplexing; instead it uses a version of
CDMA that occupies 5 MHz down- and upstream (as opposed to cdma2000,
EV- DO, etc., which use 1.25 MHz down- and upstream per channel).
Thus, eventually the buzzing side-effect of GSM will disappear.

Michael D. Sullivan
Bethesda, MD, USA
Replace "example.invalid" with ".com".

Post Followup Article Use your browser's quoting feature to quote article into reply
Go to Next message: Michael D. Sullivan: "Re: Corporate Identify -- Verizon vs. "Bell Telephone""
Go to Previous message: Mark Crispin: "Re: Strange Call ID"
TELECOM Digest: Home Page