PA enable control in wireless power amplifier

In wireless power amplifier, there is PA enable control signal (about 3V). Does anyone know how does this signal enable the PA? I know high is for enable, low is disable. But what I want to know is what is the concept behind? it turns off bias or what?

Thanks.

You should do these things properly and respectively to turn off the PA while the Load is still connected.
-Switch off the input signal
-Turn off the main bias
-Turn off the gate/base bias

Turn off the main bias.

Hard to tell, u have to read the data sheet. It might stop the drain from getting a +voltage by using a bipolar or fet transistor. It might make the gate voltage go down so that there is little or no current in the active device. In rare instances, there is an attenuator in front of the gain stages that switches off (but you would notice the drain current staying around the normal level when active).