Hello Rafael,
While I do understand your question(s) on this forum, I fear that you may be mistaken as to this forum's purpose.
This is NOT a forum to support National Instruments products. For that, try
www.ni.com and look for your specific product line.
This forum (chiefdelphi.com) is supporting a high-school robotics program. In general, high school kids won't even understand your questions, much less be able to answer them.
As for your specific question, yes, it is possible to have a waveform with only an I component: Consider the pure sine wave, as a trivial example. Not all radio signals have a Q component, although in the modern digital data world we are so often accustomed to seeing I/Q data, we have forgotten that older data methods like the TCM3105 modem chip had no Q component.
So, it depends upon your specific implementation.