ROC curves

Started by abraham007 in comp.dsp9 years ago 8 replies

Hi guys I am doing my phd related to sonar signal processing. I have implemented active sonar signal processing chain involving complex...

Hi guys I am doing my phd related to sonar signal processing. I have implemented active sonar signal processing chain involving complex demodulation, beamforming, match filter , normalization etc in MATLAB. I have tested sp chain with simulated data also. The problem i am facing now is how to set detection threshold for my active system?I have gone through some literature describing ROC curv...


phase shift beamformer

Started by abraham007 in comp.dsp8 years ago

Hi every one I am doing work on narrow band phase shift beamforming (frequency domain) and after doing various simulations, i decided to varify...

Hi every one I am doing work on narrow band phase shift beamforming (frequency domain) and after doing various simulations, i decided to varify beamformer practically. I was able to get data from an acoustic linear array of 24 elements spaced 0.17m apart. The omni directional source was placed at various bearings w.r.t linear array and was transmitting 4.4KHz CW pulses of 200ms duration . The ...


electret microphone array ----> cheap daq card ?

Started by Roger Philips in comp.dsp16 years ago 4 replies

I want to build an cheap microphone array for voice beamforming. My idea is to feed signals from 16 electret microphones to 16 single-ended...

I want to build an cheap microphone array for voice beamforming. My idea is to feed signals from 16 electret microphones to 16 single-ended inputs on a $280 "Measurement Computing PCI-DAS6013" A/D board. Are there any useful references for this idea? Does anyone see any obvious problems with this idea? Thanks, Roger Philips Graduate Student UH


Low-pass-colored output from filter-and-sum beamformer

Started by henne in comp.dsp5 years ago 5 replies

Hi all, I'm currently trying to apply some front-end processing to microphone signals before given the processed signal to an an automatic...

Hi all, I'm currently trying to apply some front-end processing to microphone signals before given the processed signal to an an automatic speech recognizer. Of course, the purpose of pre-processing is to enhance the signal, i.e., to remove unwanted interference from the recorded microphone signals. One of the things I'm doing is beamforming. I'm using a filter-and-sum beamformer. The corre...


Can anybody tell me sth. about Leaky NLMS

Started by Jing in comp.dsp14 years ago 3 replies

Hi, I am trying to implement leaky NLMS for adaptive beamforming, but I found that the noise reduction performance is worse than that of NLMS....

Hi, I am trying to implement leaky NLMS for adaptive beamforming, but I found that the noise reduction performance is worse than that of NLMS. The data I used are simulated data, and I assume the noise and speech sources are well seperated. Can anybody give me some suggestions about applying leaky NLMS for GSC? Is Leaky really better than that of NLMS? Thanks a lot! Best Regards, Jing ...


How can I know my desired signal for LMS algorithm?

Started by scc in comp.dsp13 years ago 2 replies

Hi, I've got a problem with the implementation of LMS algorithm. I'm looking for desing a Digital beamforming antenna for my...

Hi, I've got a problem with the implementation of LMS algorithm. I'm looking for desing a Digital beamforming antenna for my final project.Someone told me that it's better if I use LMS algorithm to calculate the weights of the array elements because I don't know how many users there are and those users are mobile users. My problem is that LMS algorithm needs to know the desired signal...


Time series version of MVDR beamforming

Started by Abhimanyu in comp.dsp12 years ago 2 replies

Hi, I am trying to implement a time series version of the popular MVDR beamformer. As I understand, the data for the beamformer is spatial...

Hi, I am trying to implement a time series version of the popular MVDR beamformer. As I understand, the data for the beamformer is spatial samples of a plane wave and the antenna array is steered through a range of angles to get a peak which indicates the DOA and thereby helps in estimating the source complex amplitude. I was wondering if similar concept could be applied if my data now is a win...


Question regarding beamforming on data acquired through sound card

Started by Sylvia in comp.dsp13 years ago 2 replies

I have taken data from single microphone in MATLAB work space through MATLAB data acquisition tool box as left and right channels(inorder...

I have taken data from single microphone in MATLAB work space through MATLAB data acquisition tool box as left and right channels(inorder to simulate the data from 2 microphones).Here is the code I have used for sound data acquistion. AI = analoginput('winsound',0); chan = addchannel(AI,1); chan2=addchannel(AI,2); AI duration = 2; SampleRate = 44100; set(AI,'SampleRate',SampleRate); set...


digital beamforming with Concentric circular array

Started by zafaryaar in comp.dsp10 years ago 10 replies

Hi, I'm new to DSP and i have been given a task to do simulation of Digital Beam forming using Uniform Concentric circular arrays. I have...

Hi, I'm new to DSP and i have been given a task to do simulation of Digital Beam forming using Uniform Concentric circular arrays. I have to generate (by simulation) multiple adaptive spots beams on earth by using Uniform Concentric circular array antenna on satellite. Some main things to do are; 1: generate multiple spot beams on earth for mobile communication. 2: Uniform Concentr...