Uplink Power Control in CoMP Systems via Effective Path Loss

The patent segments the multiple path losses into two categories: a reference path loss (PL_ref) and path loss differences (ΔPL) relative to the reference. This segmentation simplifies the calculation by separating the base value from the adjustments, allowing the UE to efficiently compute the effective path loss as PL_effective = PL_ref + ΔPL without needing to process all individual path losses equally.

The base station performs preliminary action by determining and signaling the reference path loss and the path loss differences to the UE before the UE performs the final effective path loss calculation. This preliminary provision of reference values reduces the computational burden on the UE and standardizes the calculation process across multiple receiving points.

The patent extracts only the essential CoMP setting information needed for power control - specifically the reference path loss and path loss differences - and transmits these to the UE. By taking out only the critical parameters rather than transmitting complete path loss data for all receiving points, the system achieves adaptability while minimizing signaling overhead.

The patent changes the parameter representation from transmitting absolute path losses for multiple receiving points to transmitting a reference path loss and relative differences. This parameter transformation reduces the amount of signaling data while preserving the adaptability needed for effective power control across varying CoMP configurations.