[RFI] Blackberry interference with conference room audio systems

[Jim P]

Leigh, I just want to be clear on this, as all people
may not have followed the 'evolution' and renaming
that GSM has gone through into it's current
manifestation - GPRS.

All this 'renaming' hasn't materially changed the
air-interface level of the underlying principle upon
which GPRS (General Packet Radio Service) is
based, and to a lesser extent, the next migratory
step, EDGE (Enhanced Data for Global Evolution).

These are based on _the same_ air-interface frame
structure, logic channel and 200kHz carrier bandwidth
and symbol rates as GSM (# bits/symbol changes in
EDGE for higher data rates, as does the modulation
format).

It's not until the last step towards "3G" cellular/data,
called (variously) UMTS and IMT-2000, that a major
change is made,and W-CDMA (Wide-CDMA) is used
for the air-interface (RF link).

Evolution of GSM to 3G/IMT-2000 via GPRS/ EDGE/ WCDMA
http://www.geekzone.co.nz/content.asp?contentid=2362

There are other 2-way wireless data networks out there
too, that actually predate today's GSM/GPRS/EDGE
networks; they were not as widely publicized as the big
cellular carriers have done in promoting their offerings ...

The original Blackberies, by RIM (Research In Motion)
actually used these other networks early on (and may
still yet to this day); networks such as Pagenet's ReFlex
R50 protocol, and PageMart's ReFlex R25 network - both
operating nationwide (originally designed for 2-way paging/
messaging, but adopted for PDAs as that fad -er-
technology matured).
.
Jim P  /  WB5WPA  /


----- Original Message -----
From: "Leigh L Klotz, Jr." <Leigh at WA5ZNU.org>
To: "Jim P" <jvpoll at dallas.net>; "Michael Germino" <ad6aa at sbcglobal.net>;
<rfi at contesting.com>
Sent: Monday, March 21, 2005 8:10 PM
Subject: Re: [RFI] Blackberry interference with conference room audio
systems


> Yes, you must be right.   It must be because the PDA type devices
> transmit more.  So it is more common with GPRS.
>
> Sorry for the confusion.
> Leigh.
> On Mon, 21 Mar 2005 10:28 am, Jim P wrote:
> >   "This seems to be a common problem with GSM phones."
>