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How to calculate the bandwidth for the Analog/Digital Modulations?

Started by kira...@gmail.com May 10, 2011
Hi,

I have a few doubts regarding the calculation of bandwidth for various Analog/Digital modulation, please correct me if I have gone wrong

Fm=Frequency of message signal.

deltaF=Freq.deviation

SR= Symbol Rate

AM = 2 * Fm
FM = 2 * deltaF + Fm

2FSK = 2 * deltaF + SR
4FSK = 2 * deltaF + SR
BPSK = SR
QPSK = SR
Will the Root Cosine Filter at the transmitter side will effect the bandwidth of modulation? How? By varying the roll-factor of Root Cosine Filter,will the bandwidth varies?
In PSK mdoulations maximum power lies in main lobe (or) main lobe and side lobes?
We can't calculate the -3dB bandwidth for AM (because the power of side lobes depends on the Mod.Index), can we calculate the -3dB bandwidth for FM, FSK, PSK modulations?

How to calculate the bandWidth for AM & FM for voice signals(Variable Fm)?

Regards,
Kiran Kumar S