hey, im in a fix here at the moment, trying to figure out how to solve this problem.
Im attempting to to a build a locationing device using ultrasound and rf signals. its a rather well researched topic, but im having difficulty understanding a certain aspect. heres just a general idea on what im attempting.
im placing pairs of RF&US (ultrasound) receivers on the ceiling beside one another. I was thinking of 9 pairs, in a systematic square like pattern. anyway, the concept is that I'm the object to be tracked, and im carrying a rf&us transmitter. i send out a pulse from each at the same time, and because RF travels much faster than US, the time difference of arrival (TDOA) of the two signals should tell me the time it takes for the US to travel to each receiver on the ceiling.
With the time known, the speed of US known, I can now find the distance from the transmitter to each receiver pair on the ceiling. With 3 or more accurate enough distances, I can now find my location through trilateration.
these are my questions, and i apologize if they are not all micro-controller related.
1) I'm attempting to this using PIC so anyone know of a PIC that can receive the first signal, and has a clock fast enough to measure the time it takes for the second to arrive?
2) If i have 1 PIC for each receiver pair, how on earth can i possibly connect all 9 pics together so i can play with the times. I need the times to eventually get into the computer so i can disregard bad ones and eventually find a location coordinate. I was thinking rs232 at first, but that wont work with 9 pics.
does any know how i can carry on from here. My knowledge on RF is limited so I'm learning as i go along.
Thanks in advance.
Im attempting to to a build a locationing device using ultrasound and rf signals. its a rather well researched topic, but im having difficulty understanding a certain aspect. heres just a general idea on what im attempting.
im placing pairs of RF&US (ultrasound) receivers on the ceiling beside one another. I was thinking of 9 pairs, in a systematic square like pattern. anyway, the concept is that I'm the object to be tracked, and im carrying a rf&us transmitter. i send out a pulse from each at the same time, and because RF travels much faster than US, the time difference of arrival (TDOA) of the two signals should tell me the time it takes for the US to travel to each receiver on the ceiling.
With the time known, the speed of US known, I can now find the distance from the transmitter to each receiver pair on the ceiling. With 3 or more accurate enough distances, I can now find my location through trilateration.
these are my questions, and i apologize if they are not all micro-controller related.
1) I'm attempting to this using PIC so anyone know of a PIC that can receive the first signal, and has a clock fast enough to measure the time it takes for the second to arrive?
2) If i have 1 PIC for each receiver pair, how on earth can i possibly connect all 9 pics together so i can play with the times. I need the times to eventually get into the computer so i can disregard bad ones and eventually find a location coordinate. I was thinking rs232 at first, but that wont work with 9 pics.
does any know how i can carry on from here. My knowledge on RF is limited so I'm learning as i go along.
Thanks in advance.