## power consumption Zigbee

Started by in comp.dsp14 years ago 2 replies

Hello All, I am trying to find out how much power does each individual circuit element consume in a low power radio. I know generally that...

Hello All, I am trying to find out how much power does each individual circuit element consume in a low power radio. I know generally that power amplifier and frequency synthesizer consume most of power. However I want some concrete numbers. I tried looking at data sheets of some radios like CC2420 but they dont specify the numbers. If anyone can point out some link/paper/tutorial etc, i...

## Energy or Power?

Started by in comp.dsp19 years ago 6 replies

I read in the books that a periodic signal can have power but a random signal has energy. I am a bit confused by this as a white noise signal...

I read in the books that a periodic signal can have power but a random signal has energy. I am a bit confused by this as a white noise signal is random yet its variance is also the average power. Can a random signal have power or am I confused...By power here I mean instantaneous power V.I and not its integral which defines average power. thanks Tom

## calculating reactive power from i(t) and u(t)

Started by in comp.dsp13 years ago 19 replies

Hello. I am sampling the current and voltage simultaniously. Right now I am calculating reactive power in two ways: 1). delay the...

Hello. I am sampling the current and voltage simultaniously. Right now I am calculating reactive power in two ways: 1). delay the current samples by a quarter of a period and then multiplying: Q=i(n+pi/2)*u(n) 2). or using the following procedure: P=1/(num. samples)*sum( i(n)*u(n) ) -> active power S=Irms*Urms -> apparent power Q=sqrt(P^2 - Q^2) -> reactive power U

## DC power transmission...

Started by in comp.dsp13 years ago 9 replies

Hello Forum, I know that electrical power travels AC and high voltage over long distances. This serves to reduce ohmic losses. Also AC current...

Hello Forum, I know that electrical power travels AC and high voltage over long distances. This serves to reduce ohmic losses. Also AC current is easily generated using mechanical methods. I have also heard about DC power transmission...does that offer particular advantages over AC power transmission? thanks, fisico32

## Definition of dBOV

Started by in comp.dsp19 years ago 17 replies

I know it's associated with digital overload power, but I'm looking for a more precise definition; something like: 0 dBOV = 10*log P1/Pref,...

I know it's associated with digital overload power, but I'm looking for a more precise definition; something like: 0 dBOV = 10*log P1/Pref, where Pref is the maximum RMS SINEWAVE power possible. The basic question is this: is it RMS power or peak power, and if it is RMS power, for what type of waveform? -- Randy Yates Sony Ericsson Mobile Communications Research Triangle Park, NC, ...

## Energy

Started by in comp.dsp17 years ago 34 replies

Where does the energy (or Power) get dissipated in a digital filter? For example, consider a simple analogue R-C low-pass filter driven...

Where does the energy (or Power) get dissipated in a digital filter? For example, consider a simple analogue R-C low-pass filter driven by band-limited white noise. The output power spectrum is given by Pout = |W(jw)|^2 * input noise power. Power is dissipated in the resistor. So for the digital equivalent wheree does the power go? Naebad

## Computing EEG power vs time

Started by in comp.dsp16 years ago 11 replies

Hi all, I am working on some EEG data and I would like to compute the power vs time. I know that i can perform an FFT to obtain the power,...

Hi all, I am working on some EEG data and I would like to compute the power vs time. I know that i can perform an FFT to obtain the power, however, this would be for specific frequencies. I read that the power = magnitude square of the voltage. Is it valid then to compute the power at each time point by squaring the voltage magnitude and then plotting these against time to obtain the EEG power ...

## Re: How do I Calculate Log Energy?

Started by in comp.dsp13 years ago 2 replies

Everyone else has their opinion on this, so I'll give you mine... The data you get from an FFT is equivalent to a voltage, but complex. To get...

Everyone else has their opinion on this, so I'll give you mine... The data you get from an FFT is equivalent to a voltage, but complex. To get the power you need to, for each sample, sum the squares of the real and imaginary parts. This gives you the square of the magnitude which is equivalent to power. Energy is not just the sum of the power, it is the integral of power over tim

## Power distribution across aliased signals

Started by in comp.dsp16 years ago 8 replies

I am having trouble understanding the effect of aliasing/imaging on the power of an output signal. Imagine I am using a DAC to generate a single...

I am having trouble understanding the effect of aliasing/imaging on the power of an output signal. Imagine I am using a DAC to generate a single frequency sine wave with frequency f well below fs/2 and with power P. Assume there is no reconstruction filter. So this frequency will image repeatedly across the frequency domain at n.fs-f and n.fs+f. I do not understand how the original power, P, i...

## lowest power for 16MIPS@16bit?

Started by in comp.dsp20 years ago 1 reply

Hello DSP gurus! For a 16bit algorithm, requiring 16 MIPS (with hardware multiplier), we want the LEAST power consuming DSP/MCU! Does...

Hello DSP gurus! For a 16bit algorithm, requiring 16 MIPS (with hardware multiplier), we want the LEAST power consuming DSP/MCU! Does anything beat 2 MSP430 controllers in parallel (= 16 mW power consumption)? For instance, if you duty cycle a 300 MHz Blackfin DSP at 5.3% (=16MIPS) , do you achieve a lower power consumption? I`m worried about the large baseline power consumption and ...

## Low-power, Low-cost DSP chip

Started by in comp.dsp20 years ago 2 replies

Ok I am hunting for a low-power AND low-cost DSP. I have searched all major manufacturers (Zilog, Intel, TI, AD, and Mot) and have not yet found...

Ok I am hunting for a low-power AND low-cost DSP. I have searched all major manufacturers (Zilog, Intel, TI, AD, and Mot) and have not yet found a suitable DSP to meet a stringent cost and power spec imposed on me. I've checked the TI 320 C6000, 5000, and 2000 series but they are just too expensive and consume too much power. The AD (blackfin, SHARC) chips appear to be no better on power ...

## Quick question, how do I supply +-5V?

Started by in comp.dsp18 years ago 25 replies

I have a large board which asks for three power supplies, +3V, +3.3V and +-5V. First two can be easily satisfied with two HP power supplies...

I have a large board which asks for three power supplies, +3V, +3.3V and +-5V. First two can be easily satisfied with two HP power supplies (each has its own GND pin also). Regarding +-5V, can I replace with an HP power supply set to 10V, -5V pin connect to HP's ground and +5V to power?

## maximum accuracy of estimating the power of the signal

Started by in comp.dsp20 years ago 7 replies

Hello, To what accuracy can i estimate the power of a signal.what are the different techniques to increase the accuracy of estimating the...

Hello, To what accuracy can i estimate the power of a signal.what are the different techniques to increase the accuracy of estimating the power of the signal.I am required to estimate the power of the signal to the accuracy of 10^-7 (i.e. the difference between estimated and actual power). I am giving the matlab code for estimating the power of the signal. In my stimation the accuracy i am...

## Digital power???

Started by in comp.dsp19 years ago 25 replies

I've asked this before in a more complicated thread, and I guess I didn't get a satisfactory answer and forgot while talking about everything...

I've asked this before in a more complicated thread, and I guess I didn't get a satisfactory answer and forgot while talking about everything else. Cool Edit gives a result called "average RMS power", which seems wrong on two counts. 1. "RMS power" is a misnomer. Should be average power, which is merely *determined* from RMS voltage (or amplitude, more generally?). 2. But what does...

## Power difference in the power spectrum density after DFT/FFT

Started by in comp.dsp14 years ago 2 replies

Hi, I am a novice at DSP techniques. I did not find an answer regarding my question in this board or DG. I want to compare the difference in...

Hi, I am a novice at DSP techniques. I did not find an answer regarding my question in this board or DG. I want to compare the difference in total power of two signal source. I know that area under the power spectral density represents total power. I also know that PSD is symmetric about the 0.5sampling frequency (Fs). So, if I show PSD from 0-0.5Fs, its area only contains half the total powe...

## Power Spectrum from Autocorrelation vs. FFT

Started by in comp.dsp16 years ago 16 replies

I have two questions: 1) Is there a difference b/w the terms 'power spectrum' and 'power spectral density'? They both seem to indicate power...

I have two questions: 1) Is there a difference b/w the terms 'power spectrum' and 'power spectral density'? They both seem to indicate power vs. frequency. 2) Suppose you are given a random sampled data sequence x[n], and you have to find its power spectrum. - Can we find the spectrum by taking the FFT of x[n] and squaring its magnitude? - Can we find the spectrum by taking the FFT of...

## difference between a power spectrum and a power density spectrum

Started by in comp.dsp18 years ago 2 replies

Hello! A friend of mine asked me this question and before answering her, I would like your opinion as well. She asked me: I have always...

Hello! A friend of mine asked me this question and before answering her, I would like your opinion as well. She asked me: I have always calculated power spectra by multiplying the FFT signal by the complex conjugate of the FFT signal (equivalent to real^2 + imag^2) and dividing by the number of points. What is the difference between a power spectrum and a power density spectrum? A met...

## Bandpass subsampling?

Started by in comp.dsp10 years ago 3 replies

There is a need to estimate power which falls into given wide (~30% of Nyquist) bandwidth. Power spectrum doesn't matter; just overall number....

There is a need to estimate power which falls into given wide (~30% of Nyquist) bandwidth. Power spectrum doesn't matter; just overall number. The power estimate is not needed often; so a decimation factor of ~1000 is preferred. Straightforward way would be make FIR filter to cut out the bandwidth, run this filter at every 1000th sample, then measure power. But if the input is period...

## Total power of PSD

Started by in comp.dsp11 years ago 3 replies

Hi, I have a Power spectral density of an EMG signal. I want to calculate total power for different frequency ranges. (For 5-12, 15-30 and...

Hi, I have a Power spectral density of an EMG signal. I want to calculate total power for different frequency ranges. (For 5-12, 15-30 and 30-60) How can I do this using matlab? Thank you very much for your time.

## Need help in analysing equations-Active Power FIlter

Started by in comp.dsp14 years ago

Hi All, I have been recently placed on a new project related to Power Systems.I am new in this field and not getting a proper place to start...

Hi All, I have been recently placed on a new project related to Power Systems.I am new in this field and not getting a proper place to start with.So please give me your advise. The project is an Active Shunt Type Power Filter used to take out harmonics from the power line. We have an existing product selling in the market,but with an old controller design, TI DSP(TMS320C40) Dual Ram