Simple SONAR Detection Question

Started by Randy Yates in comp.dsp3 years ago 9 replies

Consider the fundamental concept of a sonar (or radar) hich transmits a pulse and is looking for the return. Are there targets which...

Consider the fundamental concept of a sonar (or radar) hich transmits a pulse and is looking for the return. Are there targets which significantly distort the pulse shape, so that using a simple correlation (matched filter) for the detector results in degraded performance? In other words, it seems like what you REALLY want to use is a return, or received, signal correlator, not a transmi...


tracking sound source

Started by Sylvia in comp.dsp12 years ago 20 replies

Does any one know good material on tracking single sound source using only two microphones on a dummy head.I have seen kalman filter tracking...

Does any one know good material on tracking single sound source using only two microphones on a dummy head.I have seen kalman filter tracking for constant velocity targets etc in case of radar applications but i dont know how to use these in case of sound sources. Thanks


Predistortion of Wideband Chirp

Started by LearningDSP in comp.dsp11 years ago 4 replies

I am trying to predistort a wideband chirp for a RADAR system with approximately 1GHz of bandwidth. Currently as the frequency increases the...

I am trying to predistort a wideband chirp for a RADAR system with approximately 1GHz of bandwidth. Currently as the frequency increases the power drops off about 4dBm, and I am trying to create a flat frequency response. I have looked online at predistortion techniques and most involve a feedback loop to adjust the output of the waveform. I will be unable to do that because the equipment ...


Periodic and aperiodic autocorrelation

Started by Treviasty in comp.dsp9 years ago 3 replies

Hello ! I'm starting experiments with compressed pulse radar and I have to choose the best signal to transmit - low autocorrelation sidelobes,...

Hello ! I'm starting experiments with compressed pulse radar and I have to choose the best signal to transmit - low autocorrelation sidelobes, good ambiguity function etc. . But there is one thing I can't understand - why there are so many publications and researches about sequences with good periodic autocorrelation ? After matched filtering of incoming single pulse I have on the output the ap...


Sample Backscatter Data

Started by Mac Decman in comp.dsp6 years ago 2 replies

I seem to remember that there are some resources for sample radar backscatter data, maybe US government funded, on the internet. Anyone have...

I seem to remember that there are some resources for sample radar backscatter data, maybe US government funded, on the internet. Anyone have any clues on where to find them? I can find lots of Google links to weather data and SAR images, but at some point in the past I thought I found data for standard reflectors, cavities and other types of targets. Thanks, Mark


Superposition of Signal from three equiphase sources peturbed by Gaussian noise

Started by AdamT in comp.dsp13 years ago

Hi all, This is my first post on here, so please forgive me for any mistakes I make. Currently I'm working with simulating a system...

Hi all, This is my first post on here, so please forgive me for any mistakes I make. Currently I'm working with simulating a system consisting of a three radar horns mounted on a spherical back-plane, with an observation point placed at the focus. What I'm looking at is simulating the effect of Gaussian noise, which is being radiated from the horns with the orignal signal, on the direction o...


Radar echos in Fourier

Started by mrab...@gmail.com in comp.dsp11 years ago 7 replies

Hi, I have a simple question regarding radars and Doppler shifts. If the radars sends out a pulse p(t) then lets assume one moving targets...

Hi, I have a simple question regarding radars and Doppler shifts. If the radars sends out a pulse p(t) then lets assume one moving targets reflects it, so that the receiving echo can be written as r(t)=a*p(t-d)*exp^(j*v), where a is the reflecting coefficient, d is some delay and exp^(j*v) coresponds to a Doppler shift due to moving target. I assume that * denotes standard multiplication...


Reconstruction of time domain data using half of the frequency domain

Started by Shan9492 in comp.dsp5 years ago 3 replies

Hello all, I'm an RF engineer trying to deal with some data which was taken by sampling in the frequency domain and I don't have any expedience...

Hello all, I'm an RF engineer trying to deal with some data which was taken by sampling in the frequency domain and I don't have any expedience dealing with this type of data? I've run into a bit of a rut. I have a set of radar data sampled in the frequency domain (an I and Q pair is collected at specified range-delay positions). This was done in order to overcome several hardware limita


ADC with 50MSPS attached to DSP

Started by Stefan Fuchs in comp.dsp15 years ago 7 replies

Hi, I need to analyze echoes of a 13MHz pulse RADAR using a DSP. I would like to use a 12-bit, > 50MSPS ADC to sample the signal. Is it...

Hi, I need to analyze echoes of a 13MHz pulse RADAR using a DSP. I would like to use a 12-bit, > 50MSPS ADC to sample the signal. Is it possible to attach the ADC (e.g AD9226) directly to the parallel port of a DSP and transfer the data vie DMA? Did anyone try to attach such high-speed ADCs to a DSP? Which processor was used? Thanks a lot! Stefan


Doubt about autocorrelation

Started by psoto in comp.dsp12 years ago 1 reply

Hi, I have real data from a radar like range and azimuth, and I want to find the Center of Mass Correlation that it is correlation process...

Hi, I have real data from a radar like range and azimuth, and I want to find the Center of Mass Correlation that it is correlation process to perform a Plot Extraction sometimes called Hit processing. I found this in the page http://www.radartutorial.eu/10.processing/sp13.en.html but I don't know if I have to perform a correlation or autocorrelation for this data. thanks a lot.


MVDR filtering: Singular Correlation Matrix

Started by Master of Signals in comp.dsp14 years ago 3 replies

Hello Folks, I am trying to implement a MVDR (Minimum Variance Distortionless Response) filter instead of the usual correlation processing...

Hello Folks, I am trying to implement a MVDR (Minimum Variance Distortionless Response) filter instead of the usual correlation processing (matched filtering) for a pulsed radar application. The pulse waveform that we use is a linear FM chirp (so that the correlation operation is essentially a pulse compression). I having trouble with this because the signal correlation matrix always ends ...


Re: Complex version of an impulse

Started by Jerry Avins in comp.dsp15 years ago

Bergers wrote: ... > We have to be careful with the terms used in describing signals. Analytic > signals and complex (I and Q) signals...

Bergers wrote: ... > We have to be careful with the terms used in describing signals. Analytic > signals and complex (I and Q) signals are not necessarily the same. Reference > pages 58-59 of Radar Detection by DiFranco and Rubin. DiFranco and Rubin define > an analytic signal as y(t) = s(t) + jx(t), > where x(t) is the Hilbert transform of the real signal s(t). The Fourier > transfo


Need suggestions for literature: Radar/Sonar pulse design

Started by Rune Allnor in comp.dsp14 years ago 31 replies

Hi all. I am involved in a project where we need to design a signal for an active sonar type measurement device. My background is mainly from...

Hi all. I am involved in a project where we need to design a signal for an active sonar type measurement device. My background is mainly from seismics, where one usually isn't very sophisticated what the source is concerned ("source signal design" is usually a matter of getting an as loud "bang" as possible without using explosives). In this project there is room for more sophisticated ...


Denoising and envelop detection

Started by wolverine_w2000 in comp.dsp10 years ago 2 replies

Hi, I am working on radar processing and I am new to this study. I have 1D time domain data and I used windowing technique and 'fft'ed the data...

Hi, I am working on radar processing and I am new to this study. I have 1D time domain data and I used windowing technique and 'fft'ed the data and plotted the data using imagesc and it is a spectrogram. My question is to denoise the spectrogram and to extract the data from the envelope obtained in the spectrogram. I am working this study in Matlab. Can any one suggest me denoising algorithm and e...


Multirate filter

Started by alexgaas in comp.dsp9 years ago 7 replies

Hi everybody! I'm working on a UWB radar and i have an analog front end that samples the input signal in a nonuniform way. For the...

Hi everybody! I'm working on a UWB radar and i have an analog front end that samples the input signal in a nonuniform way. For the reconstruction filter i would use a nonuniform reconstruction algorithm from IEEE transaction on signal processing.These are links : http://www.rle.mit.edu/dspg/documents/00Eldar.pdf webee.technion.ac.il/Sites/People/YoninaEldar/Info/70.pdf The second link ...


Super-resolution technique

Started by Linda in comp.dsp15 years ago 3 replies

Hi! I have performed some propagation channel measurements in frequency domain i.e. I stored the measurement data as complex...

Hi! I have performed some propagation channel measurements in frequency domain i.e. I stored the measurement data as complex transfer function. I know I can obtain the channel impulse response by taking the IFFT. My question is, instead of taking IFFT. Can I employ other techniques (usually called super-resolution techniques in radar/wireless communications) such as ESPRIT, EM, SAGE, et...


who can help me?

Started by tiger in comp.dsp12 years ago 1 reply

I want to download a tutorial of SAR technology "Radar Interferometry" on the website "www.grss-ieee.org", but it needs a GRSS account of...

I want to download a tutorial of SAR technology "Radar Interferometry" on the website "www.grss-ieee.org", but it needs a GRSS account of IEEE member, who have the GRSS account and can help to download the tutorial? Thanks very much! I need the tutorial very much!


FMCW radar signal processing independent of sweep time

Started by Nicholas Kinar in comp.dsp12 years ago 2 replies

I am working on an application which involves a Frequency-Modulated Continuous Wave (FMCW) system. I understand that the frequency-swept wave...

I am working on an application which involves a Frequency-Modulated Continuous Wave (FMCW) system. I understand that the frequency-swept wave is sent out from an antenna toward a reflector, and the received reflection is then homodyned (mixed) with the original wave. (I understand that this mixing is a form of multiplying both signals in the time domain.) This produces a beat frequenc...


A distance-dependent frequency scaling effect multiplying the Shannon bound

Started by Anonymous in comp.dsp13 years ago 1 reply

I had recently announced, in sci.astro on 2006.03.12, about my March APS Meeting presentation of a mundane Hubble-like frequency scaling effect...

I had recently announced, in sci.astro on 2006.03.12, about my March APS Meeting presentation of a mundane Hubble-like frequency scaling effect arising purely from receiver (sampling) clock variation - just as if the universe was slowing down or speeding up relative to the receiver. This was after multiple favourable reviews in signal processing and radar at IEEE conferences in 2005, since th...


Questions about multiple signal classification algorithm

Started by fl in comp.dsp6 years ago

Hi, I read an article talking about MUltiple SIgnal Classification (MUSIC) algorithm...

Hi, I read an article talking about MUltiple SIgnal Classification (MUSIC) algorithm at: http://www.physics.sfsu.edu/~dcuneo/radar-mount/music.pdf When I read the following on page 2 (I change above bar and T to a conjugate * for difficulties in writing above bar here), I cannot understand the last line. The project matrix is still a (transformation) matrix, but it said inner