What is the modulation index?

I have a confusion here. So please help.

I have a message signal given as :

m(t) = 0.5 cos(wt) + 0.3 sin (2wt)

I also have  a carrier signal whose amplitude is known.

and now i want to calculate the modulation index. which is given as
amplitude of message signal divided by amplitude of carrier. (Remember
that i am doing AM.)

The confusion is that:

Does the amplitude of message signal be 0.5+0.3=0.8  ???
or what else??...I am unable to calculate the amplitude of message
signal which I need to calculate modulation index.

Waiting for your positive reply.

qoo wrote:
> I have a confusion here. So please help.
> 
> I have a message signal given as :
> 
> m(t) = 0.5 cos(wt) + 0.3 sin (2wt)
> 
> I also have  a carrier signal whose amplitude is known.
> 
> and now i want to calculate the modulation index. which is given as
> amplitude of message signal divided by amplitude of carrier. (Remember
> that i am doing AM.)
> 
> The confusion is that:
> 
> Does the amplitude of message signal be 0.5+0.3=0.8  ???
> or what else??...I am unable to calculate the amplitude of message
> signal which I need to calculate modulation index.
> 
> Waiting for your positive reply.

Modulation index is a property of an FM signal. The property you want is 
modulation percentage. Most circumstances that make the modulation 
percentage useful call for peak values. A quick bit of calculus will 
reveal the peak value of m(t). You probably should know how to do that.

Jerry
-- 
Engineering is the art of making what you want from things you can get.
�����������������������������������������������������������������������

On Oct 19, 3:13&#4294967295;pm, Jerry Avins <j...@ieee.org> wrote:
> qoo wrote:
> > I have a confusion here. So please help.
>
> > I have a message signal given as :
>
> > m(t) = 0.5 cos(wt) + 0.3 sin (2wt)
>
> > I also have &#4294967295;a carrier signal whose amplitude is known.
>
> > and now i want to calculate the modulation index. which is given as
> > amplitude of message signal divided by amplitude of carrier. (Remember
> > that i am doing AM.)
>
> > The confusion is that:
>
> > Does the amplitude of message signal be 0.5+0.3=0.8 &#4294967295;???
> > or what else??...I am unable to calculate the amplitude of message
> > signal which I need to calculate modulation index.
>
> > Waiting for your positive reply.
>
> Modulation index is a property of an FM signal. The property you want is
> modulation percentage. Most circumstances that make the modulation
> percentage useful call for peak values. A quick bit of calculus will
> reveal the peak value of m(t). You probably should know how to do that.
>
> Jerry
> --
> Engineering is the art of making what you want from things you can get.
> &#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;


Thanks jerry  :)

On Oct 19, 3:13&#4294967295;pm, Jerry Avins <j...@ieee.org> wrote:
> qoo wrote:
> > I have a confusion here. So please help.
>
> > I have a message signal given as :
>
> > m(t) = 0.5 cos(wt) + 0.3 sin (2wt)
>
> > I also have &#4294967295;a carrier signal whose amplitude is known.
>
> > and now i want to calculate the modulation index. which is given as
> > amplitude of message signal divided by amplitude of carrier. (Remember
> > that i am doing AM.)
>
> > The confusion is that:
>
> > Does the amplitude of message signal be 0.5+0.3=0.8 &#4294967295;???
> > or what else??...I am unable to calculate the amplitude of message
> > signal which I need to calculate modulation index.
>
> > Waiting for your positive reply.
>
> Modulation index is a property of an FM signal. The property you want is
> modulation percentage. Most circumstances that make the modulation
> percentage useful call for peak values. A quick bit of calculus will
> reveal the peak value of m(t). You probably should know how to do that.
>
> Jerry
> --
> Engineering is the art of making what you want from things you can get.
> &#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;




Thanks Jerry :) :) :)

qoo wrote:

   ...

> Thanks Jerry :) :) :)

  :) :) :) You're welcome! :) :) :)

Jerry
-- 
Engineering is the art of making what you want from things you can get.
�����������������������������������������������������������������������