- Wed Nov 29, 2006 8:05 pm
#22739
Are these devices beacons that transmit their code frequently? A critical factor will be data collision if more than one device is reporting at the same time. Any design should address collision issues. One approach is to have each device send its code 2 or 3 times with a delay between codes that is unique for each device. The will minimize that likelihood of having two or more transmitters on at the same time. If that occurs, having a different delay for each device makes it much more likely that the second or third time that the device sends its code, it will be in the clear.
Another, more complicated approach, requires the transmitters to wait for a "send your id" signal from the receiver. This is what I did for an IR beacon I built awhile ago. The receiver would send an "Is anyone out there" IR burst. Any receivers in the area would detect the signal from the receiver, wait its unique delay time, and then send its code. It worked very well, but I don't know if this approach would be suitable for your use.
Your receiver would be looking for a valid signal from a transmitter. If noise or a data collision creates garbage on the output, ignore it. The next time the tranmitter sends the code, it should be detected properly.