August 27th 07, 03:31 AM
posted to sci.electronics.basics,rec.radio.shortwave,rec.radio.amateur.antenna,alt.cellular.cingular,alt.internet.wireless
|
|
external usenet poster
|
|
First recorded activity by RadioBanter: Jul 2007
Posts: 24
|
|
A more rational approach -- how I would like to change the cell phone industry.
On Thu, 16 Aug 2007 20:29:12 +0900, "Brenda Ann"
wrote in :
"John Navas" wrote in message
.. .
On Thu, 19 Jul 2007 18:43:58 -0700, Don Bowey wrote
in :
On 7/19/07 4:42 PM, in article ,
"John Navas" wrote:
On Thu, 19 Jul 2007 14:45:00 GMT, wrote in
:
In rec.radio.amateur.antenna Radium wrote:
Digital cell phones should stop using the compression they use and
start using monaural WMA compression with a CBR of 20 kbps or less and
a sample rate of at least 44.1 KHz. In addition, the following must
also apply:
The audio bandwidth of the phone system is about 3 KHz.
Actually more like 10 KHz.
If he is commenting on the bandwidth of a message network channel/circuit,
including cellular, it is about 3 kHz.
Audio. Suggest you read more carefully.
POTS phone lines are very limited. IIRC from my work with those systems,
about 300-3600 Hz. Strictly human voice range, not meant for hi-fi. Special
lines are still available for hi-fi use as audio STL's.
POTS lines are encoded at 64 Kbps, which is why V.90 modems work, and
which is sufficient for decent audio, albeit not "hi-fi".
--
Best regards, FAQ FOR CINGULAR WIRELESS:
John Navas http://en.wikibooks.org/wiki/Cingular_Wireless_FAQ
|