This represents the current state of a radio Link.
notOperational(1): The link is not operational.
selftest(2) : Power on self test in progress
download(3): Image download is in progress.
txOnly(4): The radio link will switch to this state if
the radio link is configured for transmit only.
acquiring(5): Attempting to sync up with the far end transmitter.
receiveUp(6): The receive side of the radio link has successfully
sync'ed up with remote end.
transmitUp(7): Transmit side of the radio link is up and running.
linkOperational(8): The radio link is ready for duplex
communication.