0
$\begingroup$

if i have 2 sensors, sensor1 and sensor2, that sample a signal on complementary points so that sensor2 samples always between sensor1s sampling points. can I achieve the doubled sampling rate with the combination of both ? so with merging both samples, although they are aliased individually.

$\endgroup$
1
$\begingroup$

Yes; what you describe doesn't mathematically look any different than a single sampler at twice the rate. But they sensors need to sense the same, band-limited thing!

Actually, that's how some very high-speed ADCs work.

If you're not actually doing GS/s, getting a faster ADC would probably be easier than staggering multiple ADCs.

$\endgroup$
  • $\begingroup$ could you pls make a little bit more clear what you mean with band-limited thing? If my signal is bandlimited with a low-pass-filter to 4khz nyquist, and I sample the signal with two sensors with sampling rate 2khz but complementary sample points, i can merge them right? and what is GS/s? $\endgroup$ – Khan May 13 '20 at 19:59
  • $\begingroup$ another question, if i have a rotating machine, where i measure vibration on two axis with accelerometer sensor. I measure a phase lag in x , y axis. Do you think, combining the signals from different axis is comparable to a merge like i have decribed in my question? so merging two axis with phase lag, (if measured with aliasing) could increase the resolution, if the sampling points are known $\endgroup$ – Khan May 13 '20 at 20:19
  • 1
    $\begingroup$ If my signal is bandlimited with a low-pass-filter to 4khz nyquist, and I sample the signal with two sensors with sampling rate 2khz but complementary sample points, i can merge them right? no, if your Nyquist rate is 4 kHz, you need 8 kS/s sampling rate in total. But two 4 kS/s sensors would work. GS/s = gigasamples per second. $\endgroup$ – Marcus Müller May 13 '20 at 21:19
  • 1
    $\begingroup$ I measure a phase lag in x , y axis. Do you think, combining the signals from different axis is comparable to a merge like i have decribed in my question? No, that doesn't work. that's what I meant with "the same thing": these two sensors are observing different things. $\endgroup$ – Marcus Müller May 13 '20 at 21:20
  • $\begingroup$ ok, I understand, that the two sensors measure a different thing, but if the underlying rotation is constant, it can be considered the "same" signal and therefore lead to a higher resolution right? But I understand what you mean by that, I need the same signal to be sampled simultaneously. in the same axis $\endgroup$ – Khan May 13 '20 at 23:10

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.