Hi guyz
This is my first DSP project and its a undergrad thesis project, so forgive my
stupid question.
Im implementing an adaptive LMS algorithm to cancel background noise from a
speech. my primary mic picks up a noisy speech and the secondary mic will pick
up the reference noise. in my PCM 3003 theres only one input port. how can i
connect two mics into the PCM. since this is real time so can i do this project
using just the DSK and the PCM or should i need something else like DSP/BIOS and
RTDX.
your help is very much appriciated.
Thanks...
speech enhancement with the 6711 DSK and the PCM3033
Started by ●March 23, 2008
Reply by ●March 24, 20082008-03-24
Naamhin-
> This is my first DSP project and its a undergrad thesis project, so forgive my stupid question.
>
> Im implementing an adaptive LMS algorithm to cancel background noise from a speech. my primary mic picks up a noisy
> speech and the secondary mic will pick up the reference noise. in my PCM 3003 theres only one input port. how can i
> connect two mics into the PCM.
>
> your help is very much appriciated.
Are you saying your PCM3003 daughtercard has only one connector? The standard card should have two (2) I/O connectors
(the card contains a stereo codec). Here are a couple of pics I found:
http://www.ict.com.tw/dsp/TI/dspstarterkit/pcm3003.gif
http://www.cs.princeton.edu/~gewang/ee464/1.jpg
Maybe you don't actually have a PCM3003. Better check carefully the labeling on the daughtercard.
> since this is real time so can i do this project using just the DSK and the PCM or
> should i need something else like DSP/BIOS and RTDX.
For speech application, using sampling rate of 8 kHz, the combinatino of DSK C6711 + PCM3003 and DSP/BIOS is
sufficient. RTDX may not be much help, as it's very slow in transferring data to/from the host PC.
-Jeff
> This is my first DSP project and its a undergrad thesis project, so forgive my stupid question.
>
> Im implementing an adaptive LMS algorithm to cancel background noise from a speech. my primary mic picks up a noisy
> speech and the secondary mic will pick up the reference noise. in my PCM 3003 theres only one input port. how can i
> connect two mics into the PCM.
>
> your help is very much appriciated.
Are you saying your PCM3003 daughtercard has only one connector? The standard card should have two (2) I/O connectors
(the card contains a stereo codec). Here are a couple of pics I found:
http://www.ict.com.tw/dsp/TI/dspstarterkit/pcm3003.gif
http://www.cs.princeton.edu/~gewang/ee464/1.jpg
Maybe you don't actually have a PCM3003. Better check carefully the labeling on the daughtercard.
> since this is real time so can i do this project using just the DSK and the PCM or
> should i need something else like DSP/BIOS and RTDX.
For speech application, using sampling rate of 8 kHz, the combinatino of DSK C6711 + PCM3003 and DSP/BIOS is
sufficient. RTDX may not be much help, as it's very slow in transferring data to/from the host PC.
-Jeff
Reply by ●March 25, 20082008-03-25
I can't help with your hardware problem, but regarding your adaptive LMS
algorithm, I recently experimented with an adaptive LMS algorithm and it worked
great when the noise signal came from the same source as the noise contaminating
the speech. However, as soon as I time-delayed the noise signal (even by only a
few samples), the adaptive noise filtering performance was significantly
degraded, particularly at high frequencies because the noise in the contaminated
speech at x(n) was not very correlated to the pure noise signal at x(n-m). As
the delay increased, the noise got worse and produced a comb filter sound. Let
me know if you have better success with adaptive LMS filtering when your noise
pickup mic is displaced (time delay) from your speech pickup mic.
Thanks,
Gene
Thanks,
Gene
Reply by ●March 25, 20082008-03-25
Hi guyz
>
>This is my first DSP project and its a undergrad thesis project, so forgive my stupid question.
>
>Im implementing an adaptive LMS algorithm to cancel background noise from a speech. my primary mic picks up a noisy speech and the secondary mic will pick up the reference noise. in my PCM 3003 theres only one input port. how can i connect two mics into the PCM. since this is real time so can i do this project using just the DSK and the PCM or should i need something else like DSP/BIOS and RTDX.
>
>your help is very much appriciated.
>
>Thanks...
>
>
>
Thanks for your reply.
The image given in the Princeton link is exactly what i have. When i said i have one input in my PCM3003, i meant i have only one input port. But i need two inputs, one for my primary mic and one for secondary mic. So how can i use the PCM3003 for two inputs. Is there any daughter card with multiple inputs?
Naamhin.
>
>
>This is my first DSP project and its a undergrad thesis project, so forgive my stupid question.
>
>Im implementing an adaptive LMS algorithm to cancel background noise from a speech. my primary mic picks up a noisy speech and the secondary mic will pick up the reference noise. in my PCM 3003 theres only one input port. how can i connect two mics into the PCM. since this is real time so can i do this project using just the DSK and the PCM or should i need something else like DSP/BIOS and RTDX.
>
>your help is very much appriciated.
>
>Thanks...
>
>
>
Thanks for your reply.
The image given in the Princeton link is exactly what i have. When i said i have one input in my PCM3003, i meant i have only one input port. But i need two inputs, one for my primary mic and one for secondary mic. So how can i use the PCM3003 for two inputs. Is there any daughter card with multiple inputs?
Naamhin.
>
Reply by ●March 25, 20082008-03-25
Naamhin-
> Thanks for your reply.
>
> The image given in the Princeton link is exactly what i have. When i said i have one input in my PCM3003, i meant i
> have only one input port. But i need two inputs, one for my primary mic and one for secondary mic. So how can i use
> the PCM3003 for two inputs. Is there any daughter card with multiple inputs?
What are you missing? The picture clearly shows two (2) connectors. Each one is a stereo jack (i.e. 2 signals). So
that's a total of four -- 2 inputs, 2 outputs.
Is this not enough to handle a primary and secondary mic?
I don't get what is your issue. You have everything that you need. You should get to work on the code!
-Jeff
PS. Don't strip out the previous text from the message. If you do that then other students can't follow the thread,
especially if they come along in the future and are searching the archives. If you do this, I can't help you anymore.
> Thanks for your reply.
>
> The image given in the Princeton link is exactly what i have. When i said i have one input in my PCM3003, i meant i
> have only one input port. But i need two inputs, one for my primary mic and one for secondary mic. So how can i use
> the PCM3003 for two inputs. Is there any daughter card with multiple inputs?
What are you missing? The picture clearly shows two (2) connectors. Each one is a stereo jack (i.e. 2 signals). So
that's a total of four -- 2 inputs, 2 outputs.
Is this not enough to handle a primary and secondary mic?
I don't get what is your issue. You have everything that you need. You should get to work on the code!
-Jeff
PS. Don't strip out the previous text from the message. If you do that then other students can't follow the thread,
especially if they come along in the future and are searching the archives. If you do this, I can't help you anymore.
