The Control Resource Set (CORESET) in 5G NR is equivalent to the Control Region in LTE. However, there are some key differences between the two:
In LTE, the Control Region spans the entire channel bandwidth (CBW). However, in NR, the CORESET is localized within each Bandwidth Part (BWP). This means that the CORESET can be configured to have any frequency domain width, in multiples of 6 Resource Blocks (RBs).
Both the CORESET in NR and the Control Region in LTE can vary in time domain length. In LTE, the time domain length of the Control Region is defined by the Physical Control Format Indicator Channel (PCFICH). However, in NR, the time domain length of the CORESET is defined by the RRC parameter ControlResourceSet.duration.
The CORESET offers a number of benefits over the LTE Control Region, including:
- Improved flexibility: The CORESET can be configured to have any frequency domain width and time domain length, which gives the network more flexibility to optimize the control channel for different traffic scenarios and channel conditions.
- Reduced interference: By localizing the CORESET to a specific region of the frequency domain, the network can reduce inter-cell interference.
- Improved power efficiency: By reducing the frequency domain width of the CORESET, the network can improve the power efficiency of the control channel.