On Monday, June 17, 2002, at 06:51 , Ken Chang wrote:
> I'm not a fan of the PDC technology but DoCoMo launched service
> in March 1993, more than one year earlier than most big names
> in the GSM world. I don't think you can tell at that time ...
> that the core network features and interworking were the most
> important.
As I said, they deserve the benefit of doubt as they couldn't have
known. But later on, even in the interest of PDC itself, it would have
been beneficial to clean up the spectrum mess and there the Japanese
mobile establishment (including DoCoMo and the government) is to blame
for perpetual inaction.
> Qualcomm cdma was a great technology, only one year behind GSM
> (first launched in September 1995 in Hong Kong). it's still
> the best commercial 3G technology today.
What is far more important than the air interface itself is the fact
that the interface between MSC and BTS/BSC in GSM is standardised and
open to all market participants. This has fostered competition and
helped operators to become more independent from manufacturers, reducing
risk and cost in the process. Before GSM operators were locked in to one
vendor once they had decided on the gear they wanted to use for the
initial roll out.
> UMTS air-interface is not a good design. it's outdated already.
> even Chinese can do a better job with TD-SCDMA.
agreed.
> DoCoMo said long time ago that they don't believe in one radio
> technology, 3G or 4G, maybe never. already we have WLAN which
> doesn't care UMTS at all. multiple radio modems is the solution
> - technology develops. either built-in all-in-one modems or
> detachable cards can do it.
>
> your mobile maybe real like a wallet, with lots of pockets for
> . a SIM card
Exactly what I have been propagating. A compatible SIM that allows you
to switch technologies if you want to.
> and you'll look for ads "movie phone with 6 card slots!"
> you can decide which network - PDC, cdma, or UMTS - later.
Don't forget SDR (Software Defined Radio). While this is a big challenge
and the technology is still in the labs, it may some day (5-10 years
perhaps ?) be at the heart of each mobile communications device. Thus,
the software wold determine what the air interface is and your device
can auto-tune into whatever it finds in the ether. Also, base stations
could do likewise and tune in to a mobile that can't speak the right
interface, capacity constraints permitting.
At that point the air interface wouldn't matter much and handsets could
be taught new interfaces over the air. However, it would still be
important for operators to have non-proprietary interfaces within their
networks (such as between MSC and BTS/BSC) in order to be able to choose
which ever vendor they want and to change vendors any time they want.
This ability is probably the single most important design achievement of
GSM.
kind regards
benjamin
Received on Mon Jun 17 13:19:30 2002