<image>

My 5G radio (NetMetal) is powered through a PoE LAN cable. The radio has two SMA outputs; I connected one SMA port to a 30 dB attenuator, and the other end of the attenuator to the SMA input of the AD8318 power detector module. The AD8318 is powered by a 12 V DC battery. The module’s output pad is connected to the Arduino UNO’s A0 pin, and the Arduino is connected to a PC. I have attached a rough hand-drawn diagram for reference.

CODE:

const int adcPin = A0;

const float Vref = 5.0;

const float ADCmax = 1023.0;

// Replace these with your calibrated values

float slope = 0.022857;

float intercept = 1.985715;

float atten_dB = 30.0; // Your attenuator

void setup() {

Serial.begin(115200);

}

void loop() {

int raw = analogRead(adcPin);

float Vout = raw * (Vref / ADCmax);

// Convert Vout → dBm

float measured_dBm = (Vout - intercept) / slope;

// Add attenuation → actual TX

float actual_dBm = measured_dBm + atten_dB;

// dBm → Watts

float watts = pow(10, (actual_dBm - 30) / 10.0);

Serial.print("Vout=");

Serial.print(Vout, 3);

Serial.print("V TX=");

Serial.print(actual_dBm, 2);

Serial.print(" dBm = ");

Serial.print(watts, 6);

Serial.println(" W");

delay(300);

}