In the ESP32 module the built-in DAC and ADC are used for audio in and output, which provide just about enough resolution for voice communication. So why use ESP-NOW rather than WiFi or Bluetooth?

The FDRS uses a combination of ESP32/8266 sensor nodes for short range, and LoRa nodes for long range. The ESP nodes use Espressif’s connectionless ESP-NOW peer-to-peer protocol on which allow ...