Electromagnetic (EM) de-noising in cars is a much easier task for digital DRM services than for analogue signals, given that any present noise level will be filtered out by the DRM demodulation process (- as long as the remaining SNR/MER margins are large enough to decode the signal). In this case, the presence of such EM noise will have no impact at all on the audible audio quality of a DRM service presented to the listener.
For analogue service reception the presence of any EM noise can hardly be accepted, as the noise will be amplified along with the AM signal and be audible to the listener which is one of the current big challenges for the automotive industry. In addition, NXP offers special AM pre-processing features that allow for good AM reception even in heavily noisy environments such as electric cars. DRM reception should also benefit from these solutions.