Jitter Extraction in a Noisy Signal by Fast Fourier Transform and Time Lag Correlation

Abstract

Jitter in an electronic signal is any deviation in, or displacement of, the signal in time. This paper investigates on decomposition of two types of jitter, namely, periodic and random jitter in noisy signals. Generally, an oscilloscope generates an eye diagram by overlaying sweeps of different segments of a long data stream driven by the reference clock signal. We use the fast Fourier transform with time lag correlation of the signal since we do not have a clock reference signal and apply this technique to simulated noisy signals. We separately injected a random jitter (of known amount), periodic jitter (with known frequency and amount), and both together to various modulation frequencies of sinusoidal signals. The approach is validated by several experiments with numerous values in jitter parameters. When we separately inject random jitter (5 ps) and periodic jitter (5 ps at 4.37 MHz) to the signal, we obtained the results (4.52±0.25 ps) and (4.93±0.04 ps at 4.40±0.04 MHz), respectively.

Jitter Measurement in Digital Signals by Using Software Defined Radio Technology

“…1 -Capture the data signal, j(t) 2 -Generate the ideal signal for the above data signal, i(t) 3 -Align the signals j(t) and i(t) with respect to the first zero crossing points of either rising or falling edges 4 -Obtain the exact zero crossing points at aligned edges for each signal 5 -Calculate the jitter amount (time deviation) for each cycle 6 -Obtain the frequency spectrum of the time deviations obtained in 5 7 -Calculate the jitter parameters from the spectrum We capture the light (data) signal of the camera as our first step. In order to clearly identify the zero crossings of the signal, we smooth it with minimal impact on the signal by using the Savitzky-Golay filtering algorithm [18].…”

“…This is used to generate the ideal signal. After step 6 , we obtained jitter spectra for MESA SR4000 and 30 MHz signal for each experimental setup, separately, as Note that, we compensated the results from SDR setup by the ratio 1:100/3 (see fourth column of Table II). From Fig.…”

“…All of the above methods require a reference clock. Random and periodic jitter were extracted without a reference clock in simulated noisy signals by calculating the energy of the jitter spectrum by Anthonys et al [6]. They used Fourier analysis to construct the ideal signal from the signal with jitter.…”

Signal Processing Approaches for Jitter Extraction in Time-of-Flight Range Imaging Cameras

“…In order to reduce the number of equations, Pang proposed using the FFT which reduces the calculation time. In addition, random jitter and periodic jitter have been measured in simulated noisy signals by using frequency spectrum and calculating the energy of the jitter spectrum [39]. We used Fourier analysis to obtain the corresponding ideal signal for each simulated signal.…”