Posted by Green Xenon [Radium] on 10/28/07 01:06

Paul Martin wrote:
> In article <ujr6i3dolk1qjon2ij5tta8aip26tff9qa@4ax.com>,
> John Evans wrote:
>
>
>>Oh dear - what about the deviation?
>
>
>>The rule of thumb bandwidth required for FM (Carson's Rule) says the
>>bandwidth is given by
>
>
>>2x(peak deviation x highest modulating frquency).

What is peak deviation measured in? Hz?

>
>>So a system with a maximum modulating sinusoidal frequency of 15khz
>>using a deviation of 75khz needs 180khz bandwidth minimum.
>
>


>>Note a pulse would require a far greater bandwidth.

Require a far greater bandwidth compared to what? A sine wave of the
same frequency and amplitude?

>
> Depends on the type of pulse. A wavelet might be about the same.
>

Are you talking about the pulses [bauds] of QAM signals?

Quotes from
http://www.howstuffworks.com/framed.htm?parent=modem.htm&url=http://www.physics.udel.edu/wwwusers/watson/student_projects/scen167/thosguys/index.html
:

"The carrier signal is characterized by the number of signal intervals,
or pulses, that are transmitted per second. Each pulse is called a baud."

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