How convert a square signal to DC voltage

Dear members.

I need an idea about, how convert a square pulse from a RC receiver to DC voltage for controlling a DC motor. The square signal from RC receiver is a square pulse of 20ms, 18 of them are at low state and 2ms at high state. When the stick of the RC transmitter is down position, the high state is 1 ms, and when the stick is in up position the pulse is 2ms. In this range, from 1ms to 2ms, is the interval to increase the speed of the motor.
The maximun voltage for the motor is 3,6 volt, and I was thinking divide this increasing of speed into ten steps.

1 ms --0V
2 ms --3,6V

Any idea is welcome.
Thanks in advance.

That's a standard RC servo signal. You could use an RC servo motor to drive a potentiometer from which you get a 0-3.6volt DC signal. Then use this signal to drive a motor control H-Bridge. If you want the motor to reverse you can adjust the H-bridge such that a 1.8 volt signal equals zero speed, 0 volts equals maximum reverse speed and 3.6 volts equals maximum forward speed.

I don't see why you would use a DC voltage to control a motor since motor drivers
normally want PWM. You could use an Arduino to sense the RC receiver output
using pulseIn() and drive a PWM output from it.