5G CSI-RS has 3 Types, summarized in the below figure:
1- Non-Zero Power CS RS is used for two main purposes
- For Channel Measurement CSI reporting, Beam Management, RLF, Beam Recovery, and Mobility.
- For Interference Measurement, “Intra-Cell Interference” is mainly used to measure intra-Cell interference generated by Users during Multi-User MIMO
2- CSI Interference Measurement Resources
- Mainly used for Interference Measurement, “Inter-Cell Interference” measures the interference reported or detected from Neighbor cells during SU-MIMO
3- Zero Power CSI RS
- Define a Rate matching Pattern Serving Cell that May transmit on configured REs