orpheus
Junior Member level 3

hello
we have a project about car in/out tracking system ( which car is in park
which is out, which car is in which time and out etc.. )
i think to use 433.92 mhz premade modules from telecontrolli or
radiometrix. everything is ok to here. but i need a trigger system to the
know car is in door area and car must send code to the receiver.
if i use rf again there may be collisions some of cars can get the signal
same time and they want to try reply same time again. ( i dont want to use
receiver in the car because it is cost)
so i think to use 125khz waves for triggering. like RFID systems. i dont want to transfer energy and i need limited area illumination.
one side 125 khz transmitter coil and other side in the car 125 khz simple
receiver antenna looking forward to the transmitter antenna ( one coil and capacitor , a dioede and a simple opamp compare circuit )
the distance is about 1 meter. this is just triggering the car control computer.
i have a fex experinces in rf designs. what do you think is this idea works ?
pls share your suggestions and idea
regards.
we have a project about car in/out tracking system ( which car is in park
which is out, which car is in which time and out etc.. )
i think to use 433.92 mhz premade modules from telecontrolli or
radiometrix. everything is ok to here. but i need a trigger system to the
know car is in door area and car must send code to the receiver.
if i use rf again there may be collisions some of cars can get the signal
same time and they want to try reply same time again. ( i dont want to use
receiver in the car because it is cost)
so i think to use 125khz waves for triggering. like RFID systems. i dont want to transfer energy and i need limited area illumination.
one side 125 khz transmitter coil and other side in the car 125 khz simple
receiver antenna looking forward to the transmitter antenna ( one coil and capacitor , a dioede and a simple opamp compare circuit )
the distance is about 1 meter. this is just triggering the car control computer.
i have a fex experinces in rf designs. what do you think is this idea works ?
pls share your suggestions and idea
regards.