How to simulate a Baseband signal to RF signal in Simulink

I have a series of baseband I signal and try to mix it with a .9e7Hz carrier frequency. I made the　Ｓimulink shown below. When I run it, it says that the input type of 'Input Port' should be a complex number instead of a real number. What should I do? Am I got the correct method to do this simulation or should I change my idea?

Ｔｈａｎｋｓ！

[Harmeet gill]

Think you need to change input to IQ, if it's not already