On Aug 4, 5:55=A0pm, Vladimir Vassilevsky <nos...@nowhere.com> wrote:> amcneillywrote: > > On Aug 4, 4:12 pm, Vladimir Vassilevsky <nos...@nowhere.com> wrote: > > >>amcneillywrote: > > >>>Whats a good tone detection method if the duration of my tone is 11 > >>>samples @ 44100 sample rate or 2.494331065760e-04 Seconds > > >>As usual: do-it-yourself method or hire-somebody-else method. > > > They reaction time is not critical. i can do an event based on the > > tone detection a few seconds after the event.THe problem is i need a > > good method to detect a very short 20khz signal 2.494331065760e-04 > > Let's see what can be done. This is going to be the business; my contact > at the web site; please be particular in the description of the problem. > > Vladimir Vassilevsky > DSP and Mixed Signal Design Consultanthttp://www.abvolt.comThe goal is to send a very short signal from a transmitter device and then calculate the time it takes for the signal to be reflected back at the transmitter. My thinking around the signal being very short is that i am expecting the signal to be reflected in < 40 m.s. My plan is to detect the source signal and then wait for the reflected signal then calculate the distance between signals.
detect tone
Started by ●July 28, 2009
Reply by ●August 5, 20092009-08-05
Reply by ●August 5, 20092009-08-05
amcneilly wrote:> On Aug 4, 5:55 pm, Vladimir Vassilevsky <nos...@nowhere.com> wrote: >> amcneillywrote: >>> On Aug 4, 4:12 pm, Vladimir Vassilevsky <nos...@nowhere.com> wrote: >>>> amcneillywrote: >>>>> Whats a good tone detection method if the duration of my tone is 11 >>>>> samples @ 44100 sample rate or 2.494331065760e-04 Seconds >>>> As usual: do-it-yourself method or hire-somebody-else method. >>> They reaction time is not critical. i can do an event based on the >>> tone detection a few seconds after the event.THe problem is i need a >>> good method to detect a very short 20khz signal 2.494331065760e-04 >> Let's see what can be done. This is going to be the business; my contact >> at the web site; please be particular in the description of the problem. >> >> Vladimir Vassilevsky >> DSP and Mixed Signal Design Consultanthttp://www.abvolt.com > > The goal is to send a very short signal from a transmitter device and > then calculate the time it takes for the signal to be reflected back > at the transmitter. My thinking around the signal being very short is > that i am expecting the signal to be reflected in < 40 m.s. > > My plan is to detect the source signal and then wait for the reflected > signal then calculate the distance between signals.You chose a poor method for your needs, so you've been asking the wrong questions. You should have started with "What is a good way to do sonic ranging?" Hint: bats use clicks. Jerry -- Engineering is the art of making what you want from things you can get. �����������������������������������������������������������������������
Reply by ●August 5, 20092009-08-05
On Aug 5, 12:49�pm, Jerry Avins <j...@ieee.org> wrote:> amcneillywrote: > > On Aug 4, 5:55 pm, Vladimir Vassilevsky <nos...@nowhere.com> wrote: > >> amcneillywrote: > >>> On Aug 4, 4:12 pm, Vladimir Vassilevsky <nos...@nowhere.com> wrote: > >>>> amcneillywrote: > >>>>> Whats a good tone detection method if the duration of my tone is 11 > >>>>> samples @ 44100 sample rate or 2.494331065760e-04 Seconds > >>>> As usual: do-it-yourself method or hire-somebody-else method. > >>> They reaction time is not critical. i can do an event based on the > >>> tone detection a few seconds after the event.THe problem is i need a > >>> good method to detect a very short 20khz signal 2.494331065760e-04 > >> Let's see what can be done. This is going to be the business; my contact > >> at the web site; please be particular in the description of the problem. > > >> Vladimir Vassilevsky > >> DSP and Mixed Signal Design Consultanthttp://www.abvolt.com > > > The goal is to send a very short signal from a transmitter device and > > then calculate the time it takes for the signal to be reflected back > > at the transmitter. My thinking around the signal being very short is > > that i am expecting the signal to be reflected in < 40 m.s. > > > My plan is to detect the source signal and then wait for the reflected > > signal then calculate the distance between signals. > > You chose a poor method for your needs, so you've been asking the wrong > questions. You should have started with "What is a good way to do sonic > ranging?" Hint: bats use clicks. > > Jerry > -- > Engineering is the art of making what you want from things you can get. > �����������������������������������������������������������������������use a click wazveform over a tone?
Reply by ●August 5, 20092009-08-05
On Aug 5, 4:06�pm, amcneilly <amcnei...@gmail.com> wrote:> On Aug 5, 12:49�pm, Jerry Avins <j...@ieee.org> wrote: > > > > > > > amcneillywrote: > > > On Aug 4, 5:55 pm, Vladimir Vassilevsky <nos...@nowhere.com> wrote: > > >> amcneillywrote: > > >>> On Aug 4, 4:12 pm, Vladimir Vassilevsky <nos...@nowhere.com> wrote: > > >>>> amcneillywrote: > > >>>>> Whats a good tone detection method if the duration of my tone is 11 > > >>>>> samples @ 44100 sample rate or 2.494331065760e-04 Seconds > > >>>> As usual: do-it-yourself method or hire-somebody-else method. > > >>> They reaction time is not critical. i can do an event based on the > > >>> tone detection a few seconds after the event.THe problem is i need a > > >>> good method to detect a very short 20khz signal 2.494331065760e-04 > > >> Let's see what can be done. This is going to be the business; my contact > > >> at the web site; please be particular in the description of the problem. > > > >> Vladimir Vassilevsky > > >> DSP and Mixed Signal Design Consultanthttp://www.abvolt.com > > > > The goal is to send a very short signal from a transmitter device and > > > then calculate the time it takes for the signal to be reflected back > > > at the transmitter. My thinking around the signal being very short is > > > that i am expecting the signal to be reflected in < 40 m.s. > > > > My plan is to detect the source signal and then wait for the reflected > > > signal then calculate the distance between signals. > > > You chose a poor method for your needs, so you've been asking the wrong > > questions. You should have started with "What is a good way to do sonic > > ranging?" Hint: bats use clicks. > > > Jerry > > -- > > Engineering is the art of making what you want from things you can get. > > ����������������������������������������������������������������������� > > use a click wazveform over a tone?*waveform
Reply by ●August 5, 20092009-08-05
On 8/5/2009 8:06 AM, amcneilly wrote:> On Aug 5, 12:49 pm, Jerry Avins<j...@ieee.org> wrote: >> amcneillywrote: >>> On Aug 4, 5:55 pm, Vladimir Vassilevsky<nos...@nowhere.com> wrote: >>>> amcneillywrote: >>>>> On Aug 4, 4:12 pm, Vladimir Vassilevsky<nos...@nowhere.com> wrote: >>>>>> amcneillywrote: >>>>>>> Whats a good tone detection method if the duration of my tone is 11 >>>>>>> samples @ 44100 sample rate or 2.494331065760e-04 Seconds >>>>>> As usual: do-it-yourself method or hire-somebody-else method. >>>>> They reaction time is not critical. i can do an event based on the >>>>> tone detection a few seconds after the event.THe problem is i need a >>>>> good method to detect a very short 20khz signal 2.494331065760e-04 >>>> Let's see what can be done. This is going to be the business; my contact >>>> at the web site; please be particular in the description of the problem. >>>> Vladimir Vassilevsky >>>> DSP and Mixed Signal Design Consultanthttp://www.abvolt.com >>> The goal is to send a very short signal from a transmitter device and >>> then calculate the time it takes for the signal to be reflected back >>> at the transmitter. My thinking around the signal being very short is >>> that i am expecting the signal to be reflected in< 40 m.s. >>> My plan is to detect the source signal and then wait for the reflected >>> signal then calculate the distance between signals. >> You chose a poor method for your needs, so you've been asking the wrong >> questions. You should have started with "What is a good way to do sonic >> ranging?" Hint: bats use clicks. >> >> Jerry >> -- >> Engineering is the art of making what you want from things you can get. >> ����������������������������������������������������������������������� > > use a click wazveform over a tone?This is an old, old problem that is heavily treated since the days of early radar and sonar. The most ideal waveform for computing time delay is an ideal impulse, since the time resolution is optimal. The problem is that it's not possible to put any appreciable power in a practical "impulse" since the duration is short. For high power, for detectability, a continuous tone is good, but then you lose the time resolution. Bats, dolphins, etc., figured this out eons ago and it turns out that the real way to get "resolution" is use a waveform with a lot of bandwidth and enough duration to get adequate power in it. There are lots of different waveforms that work. It could be that your time/space resolution requirements are very low, and/or your range requirement is low, so that you could, in fact, use short bursts of tones. Some system analysis should reveal whether or not that's the case. -- Eric Jacobsen Minister of Algorithms Abineau Communications http://www.abineau.com
Reply by ●August 5, 20092009-08-05
On Aug 5, 12:44�pm, Eric Jacobsen <eric.jacob...@ieee.org> wrote:> On 8/5/2009 8:06 AM, amcneilly wrote: > > > > > > > On Aug 5, 12:49 pm, Jerry Avins<j...@ieee.org> �wrote: > >> amcneillywrote: > >>> On Aug 4, 5:55 pm, Vladimir Vassilevsky<nos...@nowhere.com> �wrote: > >>>> amcneillywrote: > >>>>> On Aug 4, 4:12 pm, Vladimir Vassilevsky<nos...@nowhere.com> �wrote: > >>>>>> amcneillywrote: > >>>>>>> Whats a good tone detection method if the duration of my tone is 11 > >>>>>>> samples @ 44100 sample rate or 2.494331065760e-04 Seconds > >>>>>> As usual: do-it-yourself method or hire-somebody-else method. > >>>>> They reaction time is not critical. i can do an event based on the > >>>>> tone detection a few seconds after the event.THe problem is i need a > >>>>> good method to detect a very short 20khz signal 2.494331065760e-04 > >>>> Let's see what can be done. This is going to be the business; my contact > >>>> at the web site; please be particular in the description of the problem. > >>>> Vladimir Vassilevsky > >>>> DSP and Mixed Signal Design Consultanthttp://www.abvolt.com > >>> The goal is to send a very short signal from a transmitter device and > >>> then calculate the time it takes for the signal to be reflected back > >>> at the transmitter. My thinking around the signal being very short is > >>> that i am expecting the signal to be reflected in< �40 m.s. > >>> My plan is to detect the source signal and then wait for the reflected > >>> signal then calculate the distance between signals. > >> You chose a poor method for your needs, so you've been asking the wrong > >> questions. You should have started with "What is a good way to do sonic > >> ranging?" Hint: bats use clicks. > > >> Jerry > >> -- > >> Engineering is the art of making what you want from things you can get. > >> ����������������������������������������������������������������������� > > > use a click wazveform over a tone? > > This is an old, old problem that is heavily treated since the days of > early radar and sonar. > > The most ideal waveform for computing time delay is an ideal impulse, > since the time resolution is optimal. �The problem is that it's not > possible to put any appreciable power in a practical "impulse" since the > duration is short. > > For high power, for detectability, a continuous tone is good, but then > you lose the time resolution. > > Bats, dolphins, etc., figured this out eons ago and it turns out that > the real way to get "resolution" is use a waveform with a lot of > bandwidth and enough duration to get adequate power in it. � There are > lots of different waveforms that work. > > It could be that your time/space resolution requirements are very low, > and/or your range requirement is low, so that you could, in fact, use > short bursts of tones. �Some system analysis should reveal whether or > not that's the case. > > -- > Eric Jacobsen > Minister of Algorithms > Abineau Communicationshttp://www.abineau.com- Hide quoted text - > > - Show quoted text -Let's say you want 10 ms resolution. Look at the difference you get if you use a sine wave that is 40 ms long, and a chirp that is 40 ms long. make two reflections 40 ms long that are 10 ms apart in time, and add them (total would be 50 ms in length). Then try to get 10 ms resolution using matched filter or correlator using the sine wave and the chirp. Maurice Givens
Reply by ●August 5, 20092009-08-05
On 5 Aug, 13:44, Eric Jacobsen <eric.jacob...@ieee.org> wrote:> On 8/5/2009 8:06 AM, amcneilly wrote:> > use a click wazveform over a tone? > > This is an old, old problem that is heavily treated since the days of > early radar and sonar.I prefer the off-shore oil exploration industry's approach: airguns! Ciao, Peter K.
Reply by ●August 5, 20092009-08-05
On 5 Aug, 21:02, "Peter K." <koots...@gmail.com> wrote:> On 5 Aug, 13:44, Eric Jacobsen <eric.jacob...@ieee.org> wrote: > > > On 8/5/2009 8:06 AM, amcneilly wrote: > > > use a click wazveform over a tone? > > > This is an old, old problem that is heavily treated since the days of > > early radar and sonar. > > I prefer the off-shore oil exploration industry's approach: airguns!TNT works, too. Used to work with people who claimed they woke up during sea trial by a 0.5 kg charge *not* going off. Personally I never got past the stage where I woke up when they did. Rune
Reply by ●August 5, 20092009-08-05
On 8/5/2009 11:51 AM, maury001@core.com wrote:> On Aug 5, 12:44 pm, Eric Jacobsen<eric.jacob...@ieee.org> wrote: >> On 8/5/2009 8:06 AM, amcneilly wrote: >> >> >> >> >> >>> On Aug 5, 12:49 pm, Jerry Avins<j...@ieee.org> wrote: >>>> amcneillywrote: >>>>> On Aug 4, 5:55 pm, Vladimir Vassilevsky<nos...@nowhere.com> wrote: >>>>>> amcneillywrote: >>>>>>> On Aug 4, 4:12 pm, Vladimir Vassilevsky<nos...@nowhere.com> wrote: >>>>>>>> amcneillywrote: >>>>>>>>> Whats a good tone detection method if the duration of my tone is 11 >>>>>>>>> samples @ 44100 sample rate or 2.494331065760e-04 Seconds >>>>>>>> As usual: do-it-yourself method or hire-somebody-else method. >>>>>>> They reaction time is not critical. i can do an event based on the >>>>>>> tone detection a few seconds after the event.THe problem is i need a >>>>>>> good method to detect a very short 20khz signal 2.494331065760e-04 >>>>>> Let's see what can be done. This is going to be the business; my contact >>>>>> at the web site; please be particular in the description of the problem. >>>>>> Vladimir Vassilevsky >>>>>> DSP and Mixed Signal Design Consultanthttp://www.abvolt.com >>>>> The goal is to send a very short signal from a transmitter device and >>>>> then calculate the time it takes for the signal to be reflected back >>>>> at the transmitter. My thinking around the signal being very short is >>>>> that i am expecting the signal to be reflected in< 40 m.s. >>>>> My plan is to detect the source signal and then wait for the reflected >>>>> signal then calculate the distance between signals. >>>> You chose a poor method for your needs, so you've been asking the wrong >>>> questions. You should have started with "What is a good way to do sonic >>>> ranging?" Hint: bats use clicks. >>>> Jerry >>>> -- >>>> Engineering is the art of making what you want from things you can get. >>>> ����������������������������������������������������������������������� >>> use a click wazveform over a tone? >> This is an old, old problem that is heavily treated since the days of >> early radar and sonar. >> >> The most ideal waveform for computing time delay is an ideal impulse, >> since the time resolution is optimal. The problem is that it's not >> possible to put any appreciable power in a practical "impulse" since the >> duration is short. >> >> For high power, for detectability, a continuous tone is good, but then >> you lose the time resolution. >> >> Bats, dolphins, etc., figured this out eons ago and it turns out that >> the real way to get "resolution" is use a waveform with a lot of >> bandwidth and enough duration to get adequate power in it. There are >> lots of different waveforms that work. >> >> It could be that your time/space resolution requirements are very low, >> and/or your range requirement is low, so that you could, in fact, use >> short bursts of tones. Some system analysis should reveal whether or >> not that's the case. >> >> -- >> Eric Jacobsen >> Minister of Algorithms >> Abineau Communicationshttp://www.abineau.com- Hide quoted text - >> >> - Show quoted text - > > Let's say you want 10 ms resolution. Look at the difference you get > if you use a sine wave that is 40 ms long, and a chirp that is 40 ms > long. make two reflections 40 ms long that are 10 ms apart in time, > and add them (total would be 50 ms in length). Then try to get 10 ms > resolution using matched filter or correlator using the sine wave and > the chirp. > > Maurice GivensAnd then vary the bandwidth (i.e., sweep range) of the chirp and see the difference as well. -- Eric Jacobsen Minister of Algorithms Abineau Communications http://www.abineau.com
Reply by ●August 5, 20092009-08-05
Rune Allnor wrote:> On 5 Aug, 21:02, "Peter K." <koots...@gmail.com> wrote: >> On 5 Aug, 13:44, Eric Jacobsen <eric.jacob...@ieee.org> wrote: >> >>> On 8/5/2009 8:06 AM, amcneilly wrote: >>>> use a click wazveform over a tone? >>> This is an old, old problem that is heavily treated since the days of >>> early radar and sonar. >> I prefer the off-shore oil exploration industry's approach: airguns! > > TNT works, too. Used to work with people who claimed > they woke up during sea trial by a 0.5 kg charge *not* > going off. Personally I never got past the stage where > I woke up when they did.What I once thought was an earthquake turned out to be thumper trucks. Jerry -- Engineering is the art of making what you want from things you can get. �����������������������������������������������������������������������
