Coupler structure and related radio frequency circuit

A coupler structure, comprising:

• a main signal line located on a first plane;
• a first coupling line located on a second plane, wherein the second plane is in parallel with the first plane and the second plane is different from the first plane;
• a second coupling line located on a third plane, wherein the third plane is in parallel with the first plane and the third plane is different from the first plane;
• and
• a spacer element connected to the main signal line;
• and
• a conductor layer located on a fifth plane, wherein:
• the main signal line, the first coupling line and the second coupling line extend along a virtual line;
• the virtual line extends along a first direction;
• the spacer element extends along a second direction for separating the first coupling line and the second coupling line;
• the second direction is not in parallel with the first direction;
• the spacer element is a conductor;
• a projection of the spacer element on the first plane is located between a projection of the first coupling line on the first plane and a projection of the second coupling line on the first plane;
• the fifth plane is in parallel with the first plane, and the fifth plane is different from the first plane, the second plane and the third plane;
• the spacer element is connected between the main signal line and the conductor layer along the second direction;
• and
• the first coupling line and the second coupling line are located between the main signal line and the conductor layer.

A radio frequency (RF) circuit, comprising:

• an RF signal transmitting end;
• a first RF signal output end;
• a second RF signal output end;
• a main signal line located on a first plane, wherein a first node of the main signal line is connected to the RF signal transmitting end and a second node of the main signal line is connected to the first RF signal output end;
• a first coupling line located on a second plane, wherein the second plane is in parallel with the first plane, the second plane is different from the first plane, and a first node of the first coupling signal line is connected to the second RF signal output end;
• a second coupling line located on a third plane, wherein the third plane is in parallel with the first plane and the third plane is different from the first plane;
• a spacer element connected to the main signal line;
• and
• a power detector coupled to a first node of the second coupling line, wherein:
• a projection of the spacer element on the first plane is located between a projection of the first coupling line on the first plane and a projection of the second coupling line on the first plane;
• a main coupling part of the main signal line, a first coupling part of the first coupling line, a second coupling part of the second coupling line and the spacer element form a coupling structure;
• and
• the main signal line, the first coupling part and the second coupling part extend along a virtual line;
• the virtual line extends along a first direction;
• the spacer element extends along a second direction for separating the first coupling line and the second coupling line;
• the second direction is not in parallel with the first direction;
• the spacer element is a conductor;
• the spacer element includes a first spacer part and a second spacer part;
• the first spacer part is connected between the main signal line and the second spacer part along the second direction;
• the second spacer part is located on a fourth plane, wherein the fourth plane is in parallel with the first plane and the fourth plane is different from the first plane;
• and
• the first spacer part includes a plurality of conductor vias disposed along the first direction or is a conductor wall extending along the first direction.