Output match directional coupler

A method of providing directional coupling comprising:

• receiving an RF signal at an input port;
• transforming a first impedance presented at an output port to a second impedance presented at the input port with a low pass filter and detector circuitry, wherein the low pass filter comprises a filter inductor and a filter capacitor, wherein the filter inductor is coupled between the input port and the output port and has a first inductance, and wherein the filter capacitor is coupled between the output port and ground;
• generating a detector current through a detector inductor that is magnetically coupled to the filter inductor, wherein the detector inductor is provided by detector circuitry and the first inductance of the filter inductor is greater than a second inductance of the detector inductor;
• and
• transmitting the RF signal from the output port once the RF signal is filtered by the low pass filter.

An RF amplification device comprising:

• an RF amplification circuit to amplify an RF signal;
• a directional coupler operably associated with the RF amplification circuit such that the RF amplification circuit presents an amplifier impedance to the directional coupler and configured to be coupled to a load such that the load presents a load impedance to the directional coupler, the directional coupler comprising:
• a low pass filter comprising a filter inductor having a first inductance and a filter capacitor, wherein the filter inductor is coupled so that the RF signal passes across the filter inductor and the filter capacitor is coupled so as to be in shunt with respect to the load;
• and
• detector circuitry coupled to the filter inductor and comprising a detector inductor having a second inductance such that the first inductance of the filter inductor is greater than the second inductance of the detector inductor, wherein the detector inductor is magnetically coupled to the filter inductor such that a detector current is generated through the detector inductor in response to the RF signal passing across the filter inductor and wherein the low pass filter and the detector circuitry cooperate to transform the load impedance to the amplifier impedance.