There are two fairly easy ways to generate the monopulse. 1) have a square wave drive a gigabit logic digital gate. AC couple into the gate, and have a shorted length of transmission line attached there too. The square wave turns into a very short pulse, and the gate acts as a buffer amp.
2) have a high power (300 mw) sine wave drive an impulse generator. The impulse generator is a series inductor attached to a shunt mounted step recovery diode. Additional input matcing and output highpass filtering helps efficiency.
For receiving, the lowest cost way is to use a "sampler circuit" and use "equivalent time sampling". This is the way oscilloscopes in the 1970's were able to display microwave signals--they used a fast input sampler hooked up to a 100 MHz oscilloscope, and just sampled the input over and over again until they saw the waveshape. Impulse radars typically vary the sampling time by using a ramping analog voltage and some comparator circuits.