What are the correct ways of connecting a long distance analog sensor?
Try a current loop. Instead of using a voltage to represent a measured quantity, the quantity is represented by a current, typically between 4 and 20 milliamps.


Current is equal everywhere in a series circuit, so the resistance and consequent voltage drop over a long wire is not a concern.
The low impedance of the circuit tends to be less prone to noise.
The same two wires can also power the sensor.
Using 4 mA as a minimum reading means a measurement of 0 mA indicates a faulty or disconnected sensor.


This is a standard interface in industrial sensors, so you should have little difficulty finding ICs or discrete designs.