| ??? 12/23/06 08:42 Read: times |
#130040 - moving or stationary? Responding to: ???'s previous message |
Russell Bull said:
So is your target moving or stationary? Like having a digital scope with 1msps and feeding it a 10mhz sinewave. You will see a sinewave, but its frequency is much lower than the input signal. That's how it was explained to me. The circuitry i've seen uses a little 'f' series ttl and a 80c51fa and gives centimetre accuracy. http://www.8052.com/forum/read.phtml?id=129803 The wave is purely a sine wave ! Russell , you seems to have worked with laser range finders , In undersampling we are not getting the frequency only some part of it , as you have earlier said " we can measure the period though " ,what good will it do (this I feel you have said in context to my earlier question as per above link , which was a different scheme) I have a moving target and the frequency oscillates between two values ,and when the target changes its position there is a phase shift( return signal) which in terem is related to the distance . I know there are phase comparators / ICs etc , I need to know HOW the slightly more wavelengths are responsible for this .say when a target is approaching and its at a distance 9meters from the sensor at this very instance two shifted frequencies are having different number of wavelengths filling the region , then how the phase shift is compared can you please explain this in context to radians .How the phase is extracted . AP |
| Topic | Author | Date |
| Phase difference calculation | 01/01/70 00:00 | |
| wow | 01/01/70 00:00 | |
| no wow | 01/01/70 00:00 | |
| Wow | 01/01/70 00:00 | |
| examples | 01/01/70 00:00 | |
| No prejudice | 01/01/70 00:00 | |
| No | 01/01/70 00:00 | |
| Thank you | 01/01/70 00:00 | |
| Welcome Alireza and | 01/01/70 00:00 | |
| Prejudice? | 01/01/70 00:00 | |
| Thanks | 01/01/70 00:00 | |
| re: no prejudice | 01/01/70 00:00 | |
| I was right | 01/01/70 00:00 | |
not at all | 01/01/70 00:00 | |
| More detail, please | 01/01/70 00:00 | |
| On paper everything is easy | 01/01/70 00:00 | |
| correction | 01/01/70 00:00 | |
| More detail, please | 01/01/70 00:00 | |
| Phase difference | 01/01/70 00:00 | |
| Wrong forum... | 01/01/70 00:00 | |
| wrong forum | 01/01/70 00:00 | |
| I should learn how to read! | 01/01/70 00:00 | |
| moving or stationary? | 01/01/70 00:00 | |
| Highly complex | 01/01/70 00:00 | |
| Other techniques | 01/01/70 00:00 | |
| Highly complex | 01/01/70 00:00 | |
| Accomplished ! | 01/01/70 00:00 | |
| So, what is the answer? | 01/01/70 00:00 |