Self-adjusting electromagnetic coupler with automatic frequency detection

A self-adjusting electromagnetic coupler assembly comprising:

• a bi-directional electromagnetic coupler having a first port, a second port, a third port, and a fourth port, the electromagnetic coupler including a main line extending between the first port and the second port, and a coupled line extending between the third port and the fourth port and disposed physically proximate the main line, the bi-directional electromagnetic coupler being configured, in a forward mode of operation, to produce a forward coupled signal at the third port responsive to receiving a first signal at the first port, and in a reverse mode of operation, to provide a reverse coupled signal at the fourth port in response to receiving a second signal at the second port;
• an adjustable termination impedance selectively connected to the fourth port when the bi-directional electromagnetic coupler is in the forward mode of operation and to the third port when the bi-directional electromagnetic coupler is in the reverse mode of operation;
• and
• a frequency detector selectively connected to the third port when the bi-directional electromagnetic coupler is in the forward mode of operation and configured to detect a frequency of the forward coupled signal and to provide an impedance control signal to tune the adjustable termination impedance based on the frequency of the forward coupled signal.