www.a00.de > tcpgroup > 1995 > msg00115
 

TCP-group 1995


[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Radios for higher speeds,



>Why it is nessesary to have a 15KHz bandwidth for 9.6Kb, when in the wireline
>case it is sufficient a 2.4KHz for 28.8Kb ??

There's a fundamental tradeoff between bandwidth and S/N ratio. On a phone
line where you have high S/N, you can use higher-order modulation schemes
to get many bits/sec per Hz.

You *could* apply these same schemes to radio channels but, as Richard
Nixon once said, "that would be wrong". Modulation schemes that give many
bits/sec/Hz are inherently more sensitive to noise and interference, which
is much more of a problem on radio than on phone lines.

Phil





Document URL : http://www.a00.de/tcpgroup/1995/msg00115.php
Ralf D. Kloth, Ludwigsburg, DE (QRQ.software). < hostmaster at a00.de > [don't send spam]
Created 2005-01-02. Last modified 2005-01-02. Your visit 2020-10-22 05:40.19. Page created in 0.049 sec.
 
[Go to the top of this page]   [... to the index page]