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Hilbert transform and SSB power??

Started by Bob November 3, 2004
I have a question on the power of SSB (Single side band) AM.

if transmitted signal is expressed as: 
 
u(t)=Ac*m(t)*cos(2pi*fc*t) plus minus Ac*H[m(t)]*sin(2*pi*fc*t),

Ac=carrier amplitude, fc=carrier frequency, m(t)=message signal, and
H[m(t)] is Hilbert transform of m(t). What is the equation for
received power (Pr) in terms of power of message signal (Pm)?

Some books say Pr=[(Ac^2)*Pm]/4, but other books say Pr=(Ac^2)*Pm.  
Which is right??

Thanks for the help.  This problem is really killing me. =)
Bob wrote:

> I have a question on the power of SSB (Single side band) AM. > > if transmitted signal is expressed as: > > u(t)=Ac*m(t)*cos(2pi*fc*t) plus minus Ac*H[m(t)]*sin(2*pi*fc*t), > > Ac=carrier amplitude, fc=carrier frequency, m(t)=message signal, and > H[m(t)] is Hilbert transform of m(t). What is the equation for > received power (Pr) in terms of power of message signal (Pm)? > > Some books say Pr=[(Ac^2)*Pm]/4, but other books say Pr=(Ac^2)*Pm. > Which is right?? > > Thanks for the help. This problem is really killing me. =)
Do the math for m(t) = 1, keeping in mind that H[m(t)] = 0. Then you'll know. -- Tim Wescott Wescott Design Services http://www.wescottdesign.com