Looks like band 3 @ 1800 Mhz.
Source : http://trak.in/tags/business/2016/06/28/rcom-4g-lte-delhi/
Apparently, from the source, it seems, we may get LTE network 'very soon', for other circles as well.
But, the speed test given in this news, doesn't even compare to Airtel 3G. However, also mentioned in news about poor reception of network @ -107 dB.
So, hope the wait is gonna over...