Mayank wrote on Jun 9th, 2009, 12:30am:Is my assertion that both side bands are equal in magnitude, is not correct ?
According to me, the actual phase noise plot will be 3dB more degraded than L(phi) one.
So we can compensate it while calculating jitter by adding a factor of 2.
Tell me if i am right or wrong ???
Not correct.
LSSB(f) is small signal mixing noise, that is, sideband noise which include both AM and PM noises.
LSSB(f) is composed of
LLSB(f) and
LUSB(f).
They are not equal. But they are almost same.
SΦ(f) is PM noise. This has no sideband.
SΦ(f) is approximately twice of
LLSB(f) or
LUSB(f).
But strictly speaking,
LSSB(f) is different from
SΦ(f) physically and conceptually.
Almost all current commercial RF simulators give PM and AM noises separately.
For example, Agilent GoldenGate give
SΦ(f) as "pnmx" directly.
Here we don't have to multiply "pnmx" by two to get
SΦ(f).
Note : "pnmx" of Agilent GoldenGate is twice of "pnmx" of Agilent ADSsim. And GoldenGate also give
LLSB(f) and
LUSB(f) as "side_band_left" and "side_band_right" respectively.
In Cadence Spectre Pnoise Analysis,
For noisetype="sources",
you can get Phase Noise in "pnoise of Direct Plot Form" as
LUSB(f) if you use postive offset frequency value.
For noisetype="jitter" or "modulated",
you can get
LLSB(f),
LUSB(f), AM noise, PM noise in "pnoise modulated of Direct Plot Form",
and also you can get Phase Noise in "pnoise jitter of Direct Plot Form" as true
SΦ(f).
Here this PM noise is 0.5*SΦ(f) which is same as "pnmx" of Agilent ADSsim.Phase Noise in "pnoise jitter of Direct Plot Form" is about 3dB larger value than
LUSB(f).
But this is not 2*
LUSB(f). This is true
SΦ(f).
Here we don't have to multiply Phase Noise in "pnoise jitter of Direct Plot Form" by two to get
SΦ(f) as same as in Agilent GoldenGate.