21 Jun Reliable Reception on the Road – Your Question Answered
Our best specialists will respond in brief to your questions. We will post them regularly. Please submit them in writing and in audio with your picture and we will post the answers here. Please keep your questions short and relevant and send them to: projectoffice@drm.
Almost 3 million cars with DRM in India. Great. But isn’t digital coverage in cars in cities of poorer quality as high buildings might cause signals to “drop out”?
(British digital radio hobbyist)
DRM features error-correction technology within its digital data stream. This can be set to be more rigorous in areas of high interference, depending upon the broadcast technique and propagation physics. This error correction provides either continuous service, or silence. Note that if receivers detect low signal strength, and increased rate of error, the signal also contains data on other nearby frequencies and the receiver – if it features this function – can automatically retune.
DRM can also rely upon the same broadcast at FM quality in the MW and SW bands, if provided, and switch seamlessly between services depending upon signal strength. Technologies to improve analogue radio reception in cities apply equally to DRM transmissions in these band. This includes classic antenna-diversity setups in cars to overcome local FM band cancellations as well as new approaches to receiver optimisations to overcome in-car electromagnetic noise with innovative technology for the AM bands. In general, digital signals have the benefit of travelling relatively well between buildings (or along valleys) rather than creating immediate distortion as reflected analogue signals would do.
