Generations of different frequency bands

I want to generate different frequency bands or different channels in same frequency band using matlab code or simulink model. Please suggest me how i can achieve or create bands of different frequencies.

Let us consider that i want to create 10 channels in frequency band of 100 MHz to 150 MHz. or i want to create frequency band of 150 MHz to 200 MHz , 200 MHz to 250 MHz till 500 MHz.

Thanks in advance