Uplinking in simple terms is transmitting signals from Earth station to a Satellite using a Dish with BUC-LNB (Block-Up Converter) running at higher C-band frequencies. The high power beam is sent to a Satellite's receiving transponders to be sent back to the Earth for Downlinking by viewers and cable operators, MSOs etc within that satellite transponder's footprint.
The 20+ dishes are not only for Sanskar, but it is the garden of the NSTPL Teleport company which uplinks hundreds of channels to various satellites.