PCB onboard antenna design
First of all, it is recommended to design the antenna as a component package according to the size, which is convenient for placement and subsequent project design, and can prevent the size change caused by dragging and modifying it back and forth. Secondly, the antenna is connected to the ground wire. No components or wiring should be applied around the effective part of the antenna and its lower layer (i.e. the back), and copper should not be laid, otherwise it will affect signal transmission and reception, and may not even work properly. Third, the grounding point of the antenna requires a large area of grounding, and more holes should be punched. Fourth, the antenna is required to be designed on the edge of the PCB, facing the front panel as much as possible, and it is required to avoid iron structural parts around.
PCB material conditions
Please select PCB material: FR4, dielectric constant of 4.2.
F-type antenna design reference
Figure 1. Dimensional design of F-type antenna
External antenna design
Please disconnect the PIFA antenna connection circuit and connect the external antenna with a 10pF capacitor. The wire material of the external antenna requires 50 ohm high-frequency shielding cable, and the 3CM long shielding layer shoue be removed at the tail. Weld the middle signal wire of the wire head to the output end of the antenna, and the shielding iron wire should also be welded to the position of the near ground wire. The tail of the antenna should be placed at the front of the front panel or lead out of the iron shell.