I've designed a monitoring transmitter-receiver system in which the o/p of the receiver is :
1> A rectangular wave of peak-to-peak voltage 4.6V, on-time 600usec, off-time 800usec when the transmitter signal is being received.
2> A DC voltage of 1.7V when the transmitter signal is absent.
How do i use this condition so that the uC knows when the transmitter signal is absent ?
If your micro has an ADC or a comparator, this is your best option to convert the voltage two times to make sure it wasn't just a transition that you sampled. If two times the value is within a narrow margin of 1.7V, you can be sure it is inactive.