An object, which causes the way change to the radio support rate as the given mode when it's been modified.
The meaning of the value in the enum list describe as following.
Auto mode means the radio could working on all of the radio's support rates and hwRadioRateValue has the rate, which may be below or equal max rate automaticly.
Designate mode means you can set a radio's specified support rate by the node hwRadioRateValue.