Esp32 Crystal Oscillator Layout; Esp32 Rf Layout - Espressif Systems ESP32 Hardware Design Manuallines

2. SCHEMATIC CHECKLIST AND PCB LAYOUT DESIGN
Figure 14: ESP32 Crystal Oscillator Layout
2.2.1.5 RF
The characteristic RF impedance must be 50Ω. The ground plane on the adjacent layer needs to be complete.
Make sure you keep the width of the RF trace consistent, and do not branch the trace. The RF trace should be
as short as possible with dense ground via stitching around it for isolation.
However, there should be no vias for the RF trace. The RF trace should be routed at a 135° angle, or with circular
arcs if trace bends are required.
π-type matching circuitry should be reserved on the RF trace and placed close to the chip.
No high-frequency signal traces should be routed close to the RF trace. The RF antenna should be placed away
from high-frequency transmitting devices, such as crystal oscillators, DDR, and clocks (SDIO_CLK), etc.
In addition, the USB port, USB to UART chip, UART signal lines (including traces, vias, test points, header pins, etc.)
must be as far away from the antenna as possible. It is good practice to add ground vias around the UART signal
line. It is recommended that the design of PCB onboard antenna be based on Espressif's Type-A antenna.
Figure 15: ESP32 RF Layout
Espressif Systems 18 ESP32 Hardware Design Guidelines V2.1