What is the benefit of having multiple types of DMRS?

Hi all,

So there are two types of DMRS. Type-A and Type-B.

I do not understand what’s the point of having these two types? Why didnt 3GPP just decide on one type, in my opinion PDSCH type B.

Is it there to support URLCC?

@shanjaffry ,

I think that could be because of DSS scenario if i am not wrong because in order to cover LTE RE’s there is chance of conflicting So to avoid that there of different type of DMRS types.

Please correct me if i am wrong.

My wild guess is that two types of DMRS is to accommodate slot based (using DMRS type A) and symbol-based resource allocation in the time domain (using DMRS type B). But I need to have my opinion checked by other experts as well.