Hello, I am currently going through theory on signals. While I am able to understand the math part of it, I am not able to fully understand...

Hello, I am currently going through theory on signals. While I am able to understand the math part of it, I am not able to fully understand how classifying a signal as energy or power is useful. Can someone clarify ... _____________________________ Posted through www.DSPRelated.com

Hi Since the power is more relevant to analyze than the amplitude I have come up with the idea of using signed square ss(x) = x^2 for positive...

Hi Since the power is more relevant to analyze than the amplitude I have come up with the idea of using signed square ss(x) = x^2 for positive x and -x^2 for negative x or ss(x) = (x^2)^(1/2)*x = sgn(x)*x^2 Instead of analyzing the power as the square of the amplitude the signed power could be used instead. This would preserve more information of the original signal. The or

Hello all, I have an audio app which generally displays dB levels as SPL calculated using dB = 20 * log10(p/p0) But I want to also display RMS...

Hello all, I have an audio app which generally displays dB levels as SPL calculated using dB = 20 * log10(p/p0) But I want to also display RMS levels. Is it more typical to calculate these values as a pressure level (using 20*log...) or as a power(intensity) level (using 10*log...) Any help, thoughts or opinions much appreciated. Cheers, Ben

Hi, I have a power spectrum and I want to get the frequency bands. Should I use a band-pass filter first to get the bands, or can I simply...

Hi, I have a power spectrum and I want to get the frequency bands. Should I use a band-pass filter first to get the bands, or can I simply divide the PSD data at needed frequencies? Than you..

Hi, How can I visualize the one and two-sided power spectral densities? As I can see, the former is for the real signal and the latter is for...

Hi, How can I visualize the one and two-sided power spectral densities? As I can see, the former is for the real signal and the latter is for the complex, but why are these values No/2 and No, respectively? Thanks.

Let's say there is a sine wave signal, and an amplifier with limited output amplitude. To produce maximum output power at fundamental frequency,...

Let's say there is a sine wave signal, and an amplifier with limited output amplitude. To produce maximum output power at fundamental frequency, the sinusoid could be clipped into square wave. So far so good. What if the input is a short burst of a sum of several unrelated sine waves with different amplitudes and the goal is to match given amplitude spectrum and generate maximum power? ...

I've got an upcoming application where I'm going to be looking to use some multiplexed ADC channels to do power supply monitoring. This is...

I've got an upcoming application where I'm going to be looking to use some multiplexed ADC channels to do power supply monitoring. This is a side function, a nice-to-have rather than core functionality. I'd like to be able to report as a running thing for each rail monitored both the DC value and peak-to-peak ripple. Reporting speed doesn't matter. Algorithmic complexity only matters inso...

Hi all I m trying to fix this weird behavior that I see from a data obtained from a terahertz spectroscopy analysis. The final data generated...

Hi all I m trying to fix this weird behavior that I see from a data obtained from a terahertz spectroscopy analysis. The final data generated out of the spectrometer software and i have perform some analysis on them. The first step I need do is take fft of the data to able to see its features in frequency domain but i observe a bizarre pattern. The power spectrum shows echo type of patterns . T...

For the last century or more power utilities have been putting ripple voltages on AC power lines at a few hundred Hz, with an amplitude that is...

For the last century or more power utilities have been putting ripple voltages on AC power lines at a few hundred Hz, with an amplitude that is a couple of percent of the mains voltage itself. These ripples are used for various purposes, like tariff switching and turning on street lights on foggy days. Because its old, and detectors used to be implemented with clunky resonant electro-mechnical met...

Hi friends, have a problem: have not taken HP USB ICE emulator power supply, but have free one for ADSP-21469 EZ Kit - may I use it...

Hi friends, have a problem: have not taken HP USB ICE emulator power supply, but have free one for ADSP-21469 EZ Kit - may I use it ? Regards Roman Rumian

I'm creating an FFT-based real-time analyzer for audio (i.e. live sound,) and have pretty much everything figured out except for this one thing:...

I'm creating an FFT-based real-time analyzer for audio (i.e. live sound,) and have pretty much everything figured out except for this one thing: should I plot the power spectrum (log of the _square_ of the magnitude of FFT outputs,) or the amplitude spectrum (log of the "plain old" magnitude of the FFT outputs)? (I think I'm using these terms correctly; correct me if I'm wrong.) Every desc...

I'm measuring V and I instantaneously and feeding them into a computer for an ac motor. Is there an easy way to find the Power Factor ie...

I'm measuring V and I instantaneously and feeding them into a computer for an ac motor. Is there an easy way to find the Power Factor ie the cosine of the angle between V and I ? I suppose there is zero crossings but there will be some noise of course. H

Friends, In the field of switching power supplies or other power supply architectures in which a switching signal is used, and a...

Friends, In the field of switching power supplies or other power supply architectures in which a switching signal is used, and a signal (output voltage) is sampled and used for control, the prevailing wisdom is that the ADC sample clock should be synchronized so that it samples "between" the switching clock edges and thus avoids coupling the switching noise into the samples. I say this ...

hello Forum, a question regarding the way voltage "works" in a particular transmission application. In the mountains, I have seen power...

hello Forum, a question regarding the way voltage "works" in a particular transmission application. In the mountains, I have seen power transmission power lines that use only one metal wire. The second wire (return wire) is represented by earth, i.e., the first wire is stuck straight into the ground. Isn't that equivalent to complete the circuit with a incredibly large resistance that dissi...

My question is about the Shannon bound.. The Shannon bound tells us the upper limit of information capacity for a given AWGN channel...

My question is about the Shannon bound.. The Shannon bound tells us the upper limit of information capacity for a given AWGN channel bandwidth and and available power. For any given AWGN channel BW there is an optimum modulation order and coding to get the best throughput for a given available power. The Shannon bound tells us this upper limit of capacity for that AWGN channel. What a...

Dear all, for quite a while I struggle with the following problem : Having a 3-D Array of equally data in X,Y & Z , I want to calculate...

Dear all, for quite a while I struggle with the following problem : Having a 3-D Array of equally data in X,Y & Z , I want to calculate the power spectra. ============= #include "fftw3.h" #include #include #include #include using namespace blitz; main(int argc,char **argv) { // Blitz++ is an c++ class for faciliating array ha

Hello everyone... I am using a Narrow Digital FIR Bandpass filter to filter a signal at the output of an 8 bit ADC...I calculate the envelope...

Hello everyone... I am using a Narrow Digital FIR Bandpass filter to filter a signal at the output of an 8 bit ADC...I calculate the envelope at FIR ouput(I^2 + Q^2) using the complex outputs of the FIR bandpass filter..I want to express the FIR output envelope signal in terms of the power of the input signal...how to do it? What factors do i have to consider? My ADC full scale swing is 870 mV....

Hi a couple of quick questions... (1). When using the Welch's overlapped segments method to produce a periodogram, is there a general rule of...

Hi a couple of quick questions... (1). When using the Welch's overlapped segments method to produce a periodogram, is there a general rule of thumb for the number of windowed segments? If it helps my time series are typically less than 200 elements. Or is it just a resolution tradeoff? (2). When comparing two periodograms, is it only appropriate to transform the data into relative power rath...

Hello, I've a practical question regarding Digital Control Systems (specifically Switched mode power supply) implemented on DSP chip. Since that...

Hello, I've a practical question regarding Digital Control Systems (specifically Switched mode power supply) implemented on DSP chip. Since that a controller is kind of IIR filter, I think this place is very suitable to this question. In power systems, the DC-DC converter (Buck, Boost, etc..) is normally described by a transfer function relating input - PWM duty-cycle and output - the analog...

Hello, Per definition a white noise signal has a zero mean value. yet by definition also , it has a flat power density, i,e. every...

Hello, Per definition a white noise signal has a zero mean value. yet by definition also , it has a flat power density, i,e. every frequency including zero has the same power which means it has a DC value, hence its mean is not equal to zero. I am confused. any help please?