M one-port reflection type amplifier

Hi, guys
who have experience or resource about design of the reflection microwave amplifier?I don't mention the oscillator here, I mean the amplifier with only one port: act both input and output
Please share your precious something with me , Thnaks first!
BR!

Do you mean a negative-resistance amplifier?

If the device has negative resistance, then the reflection coefficient will be better than 1. so, it's possible to amplfy the signal using only one port.

Here the input is incident wave, and the output signal is reflected wave.

Regard.

Yes, you are right!
The reflection amplifier input resistence should be negative,but it should not be oscillation when no signal incident.
I would like to see any design examples as my reference.
BR!