i) Each ANT channel must be defined as a master or a slave, master channels are effectively transmit windows which can receive afterwards and slave channels are receive windows which can transmit afterwards.
ii) You have a couple options (but channels must be assigned as master or slave)
Have every peer open a master channel on the same RF channel/network key, and then use a
background scanning channel to listen for every other open master channel, you will then "hear" every message every other peer may be transmitting. ANT will handle master channel coexistence for you as ANT master channels are designed to drift away from each other in the time domain if interference occurs.
Or, instead of a background scanning channel, you may also keep opening slave channels to keep pairing to a new master channel instead of background scanning (you cannot find yourself in a search), or using the
exclusion/inclusion list to keep searching for new nodes.
Once one peer finds the other, one of the channels can be closed as
channel's are bi-directional.
I've linked in a couple relevant application notes. Another note, background scanning channel will pick up effectively all messages from other peers on devices which can use high duty searches such as multi-mode comm chips on phones or the USB-m stick.
