Mixing carrier signal and data signal?

[imp]

Is there any method other than using NAND Schmitt Trigger
for mixing carrier signal and data signal?

 

[pewang]

If data rate is low, try to modulate the supply power of carrier sourse,however it,s not convenience than schmitt.
or use data to pull a vco which normal output is carrier frequency

 

[Hyperfrequence]

Whatever the solutions, pay attention to the resulting bandwicth modulation that could not match with the NAND circuit.