Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [phase-noise]

15 questions
9
votes
2 answers

Phase noise of op-amp

Suppose I have a carrier signal with low-ish RF frequency (a few MHz) that I can reasonably amplify with an op-amp. How can I estimate the added phase noise due to the amplifier? For microwave frequencies, gain blocks often have specifications of…
polwel
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5
votes
1 answer

Can phase noise be averaged out?

I have an ADC sampling a downconverted RF signal at fs. I obtain N=2^15 samples of the RF input signal "fcarrier + fs/10". The more I average, the more the entire noise floor shifts down (as expected, 10dB/dec) but also the phase noise skirt. I can…
divB
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4
votes
2 answers

Phase noise reduction in LC oscillator with a high-loss capacitor

I`ve got a capacitive vibration probe whose base capacitance may vary from 4 to 10 pF due to manufacturing/installation tolerances, whereas vibrations it detects can only alter its capacitance in sub-pF range. To translate capacitance into voltage…
hidefromkgb
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4
votes
1 answer

A capacitor as loop filter of a DLL

I know that if a second order, type two PLL has only a capacitor as its loop filter, it is unstable because its phase margin would be zero. but why is it ok for a DLL to only have a capacitor as its loop filter and it doesn't need the resistor in…
Fateme
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2
votes
0 answers

How to interpolate phase noise curves?

I am trying to calculate the phase jitter of a transmitter. A phase noise profile is given, say: +------------+-----------------+ | Offset (f) | L(f)_dB [dBc/Hz]| +============+=================+ | 10 Hz | -58 …
rksat
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2
votes
1 answer

Two details about phase noise have been confusing me for a long time. Hope to be resolved

Just like FLOYD M. GARDNER said in the PhaseLock Techniques, 3rd Edition: "In light of that success in spectrum analyzers, a practitioner’s answer to the question above is: The spectrum of phase noise consists of the data delivered by a phase-noise…
wu yi
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1
vote
0 answers

Conversion of phase noise unit from V^2/Hz to rad^2/Hz

I have been trying to measure the phase noise of an oscillator with a homodyne interferometric measurement with an I Q mixer in the microwave domain. The output I and Q are digitized. So, after calculating the Fourier transform, the PSD is in the…
Greta
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1
vote
1 answer

Error with phase noise to jitter calculation

I'm trying to get the jitter for an oscillator. The nominal frequency \$f_0\$ is 10 MHz, I'm integrating from 1 Hz to 100 kHz. The specifications are given as "RF Output Phase Noise (SSB)", in dBc/Hz. The formula I'm using is: \$x_{RMS}=\frac{1}{2…
pserra
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0
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0 answers

Frequency offset for phase noise measurement

I've recently designed an oscillator for a frequency range of 80 - 100MHz. I would like to analyse the phase noise of the oscillator. From my knowledge of "phase noise", it is the power of a frequency, given a certain offset from the carrier,…
Suva23
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0
votes
1 answer

How to calculate the phase noise contribution of an active loop filter in PLL

I want to calculate the contribution of each phase-locked loop (PLL) module to the total phase noise that has been done in ADIsimPLL. I'm having trouble calculating the contribution of the loop filter to the phase noise. As is mentioned in the…
shang xu
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0
votes
1 answer

Phase noise units: dBc/Hz --> dB(rad/√Hz)

Trying to better understand phase noise units and characterize a device to compare with specs. I'm used to measuring in dBc/Hz, but the specs given are in dB(rad/√Hz)/m, which I guess is fairly obviously related to the other common phase noise units…
Connor Skehan
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0
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why the control voltage of VCO in CP PLL oscillates?

I built a verilogA model for every block used in PLL, I replaced a verilogA model for VCO with a designed one but, I got oscillations imposed on the control voltage as shown below. Fdiv is the frequency of the signal at the output of divider vc is…
Mohamed Ossama
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0
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0 answers

Does the profile of phase-noise power spectrum density (PSD) vary with time?

I will promptly provide any detail or revise my question aimed at any feedback. Does the profile of phase-noise power spectrum density (PSD) vary with time? The conclusion may be that it won’t basically vary with time or it won't do that within a…
wu yi
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0
votes
2 answers

The mean value of phase noise as a stochastic process

What is the mean value of phase noise as a stochastic process? Where can I get a theoretical analysis of this topic?
wu yi
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0
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1 answer

Single tone signal generation at microwave frequency with best phase noise and spurious performance

What is the best way to generate a single tone signal with best phase noise and spurious performance? Is frequency multiplication the best way? single stage multiplication or multi stage multiplication? I want to produce a single tone 6 GHz signal…
Meryem
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