I am working on wireless communication system. We are using around 10 pairs of transmitter and receivers. We are using atmega16 microcontroller for encoding and decoding by USART ports.
Now we are able to transmit the data and receive the same in the receiver end, but there is a major problem, when we are finding the 2 transmitter data coming at the same time. The receiver is unable to get it due to interference.
Suppose one transmitter sends "SENDA" at the meanwhile another transmitter sends "GETTS", at that time the receiver can not receive proper data. As all the transmitters and receivers are working in same frequency, so this interference is occurring. How can I resolve this issue?
Best Answer
Developing a workable RF communications protocol is apt to be a tricky but educational exercise. A few additional points to consider beyond what's been said:
The consensus problem can be especially vexing if one is trying to save energy by powering down receivers when they're not needed. Suppose two P and Q are supposed to communicate once every 10 seconds, so they power up and P sends Q a packet. Q receives the packet, sends his acknowledgment, and--knowing that P won't be sending anything for almost ten seconds, powers down. If P doesn't get Q's acknowledgment, he'll retransmit; since Q is asleep, however, he won't hear P's retransmission. From Q's perspective, that wouldn't matter (he's already received his data), but it means no matter how many times P retries, he'll have no way of knowing Q got his packet (at least not until the next rendezvous in about ten seconds).
As said, a workable RF communications protocol is apt to be a tricky exercise. Still, I'd expect you'll probably learn a lot from the experience.