Here is an article about the recently concluded DRM+ tests going on in New Delhi, India. What I find remarkable is the comment "It could be successfully received up to 28 km on the first day and is comparable with that of analogue FM station operating at 5 times the power of the DRM+ signal."
Why is HD/IBOC harder to receive than analogue FM? If this is true (about DRM+) we in North America were sold a "pig in a poke" from iBiquity.
I do realize that the IBOC sidebands are currently operating at much lower power than the main analogue FM.
Here is the Press Release (regarding the test) from the consortium.