USRP modify carrier frequency

[Eoneul]

Hello, I am a student studying the USRP N200 model.

I tried the rough TX/RX functions, and I'm wondering if it's possible to change the signal equation, so I decided to leave a message.

And I use this code. 

 

I confirmed in the guide that the signal equation for this device is

s(t) = a(t)cos(2π(carrier frequency)t + Ø(t)).

I would like to create

s = b(t)∑cos(k*another carrier frequency)*t + Ø(t)).

Here, b(t) is a different constant, and ∑ is from k=0 to n.

Is there a way to modify this in the block? I can't seem to find a direction, so I'm writing for advice. Thank you.