Zynq UltraScale+ RFSoC family introduced disruptive integration and architectural breakthrough for 5G wireless and RF-class analog applications that can directly support the entire 5G sub-6GHz band. This innovative family is now shipping in volume production. This design demo shows that the multi-channel (either 8T8R or 16T16R) Zynq UltraScale+ RFSoC evaluation tool Tool is used to configure the RF-DAC and generate 2 modulated signals with 100MHz wide at 3.5GHz RF frequency (i.e., 5G band N78). The modulated I/Q mixed signal is then looped back to RF-ADC for analysis with digital down-converted to baseband. This demo shows that the Zynq UltraScale+ RFSoC device offers greater flexibility and simplifies the 5G system and software-defined radio applications.