I am interested in your prodduct SparkFun GPS Breakout - NEO-M9N, SMA (Qwiic) (GPS-17285) and would like to confirm some technical details. I plan to only buy this product not others.
1. Is it possible to measure distance by transmitting and receiving signals via Wi-Fi or Bluetooth with an ESP module? If so, what is the maximum distance range that can be achieved?
2. I am also considering using a GPS module. Would it be possible to measure distances greater than about 500 meters (for example, across an area larger than a sports field)?
It doesn’t support RTK so sending it data probably won’t help accuracy much. Figure several metres. Even with RTCM3 for DGNSS it’s going to be over a metre.
Range of WiFi in ideal case is a few hundred metres. Not sure of ESP32 but sort of thing you could quantify with GNSS in your own situation / implementation.
Yes, we use this method (called fingerprinting) in rare cases for indoor location tracking.
[Google Quote] Indoor location fingerprinting is a method that uses a “radio map” of unique wireless signal patterns to determine a location indoors.
You can use Bluetooth and WiFi both. As Clive says, several hundred meters can be expected outdoors in a good environment. Obviously you will need stationary sources of RF.
This takes a good bit of work to establish the RF base map, but I’ve seen location accuracies of several meters indoors.