UWB detection is somewhat similar to CDMA. For CDMA, the baseband siganl is narrow-band and it depends on the higher frequency chips to spread the narrow-band signal. For UWB, the baseband signal itself is already wide-band. But the detection is still based on the collection of the energy of multiple pulses to improve SNR.
For high data rate UWB, OFDM is often used. The interference from other bands still could be a problem and that is why the 5GHz band is avoided.