The most basic high-frequency PCB has 4 layers and consists of the RF system and the digital circuit.

The upper layer or the front side of the high-frequency PCB is the RF system. It consists of a high-frequency circuit and two embedded PCB antennas.

The second layer of the high-frequency PCB is the ground layer. It supplies power to the circuit and also shields the signal radiation and coupling.

The third layer is the power layer, which supplies power to the circuit and also shields the signal radiation and coupling.

The bottom layer or the backside of the PCB is the digital circuit.

Above is the most basic high-frequency PCB structure. In fact, many high-frequency PCBs have 4 or 6 layers. To avoid signal radiation and coupling, high-frequency PCBs usually use many decoupling capacitors and high-frequency choke beads.