Design an ultrasonic transceiver

I did one once for a client. Instead of running AM modulation (as usual) and avoiding the resonance peak, I ran FM *inside* the resonance peak. Decoded with a couple stages of op-amp and a PLL. Worked great for nearly a mile on nive volt batteries.

if you mean driving a single ultrasonic transducer, which is also used for receiving,

If you're asking about a bi-directional communication link. Then AM or Phase/FM modulation can be used to modulate the 40KHz carrier and then a detector to demodulate it. Transceiving analog (i.e. where the modulating waveform is analog) is a bit harder than digital, which can be done with on/off keying, frequency shift, phase shift, pulse position or pulse width modulation. You should be able to adapt IR remote control circuits for this, since they also operate around 40KHz.

Later, -ingo