Terminal Pathloss Calculation via MAC CE Updates
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In future radio communication systems, such as NR, the accuracy of pathloss calculation for uplink transmission power control based on downlink reference signal measurements can be reduced due to the update frequency of DL-RS, leading to decreased system performance, including reduced throughput.
Innovation Solution
A terminal is equipped with a receiving section to receive a pathloss reference signal and a control section that calculates pathloss for transmission power control using L1-Reference Signal Received Power (RSRP) when the pathloss reference signal is updated by a media access control-control element (MAC CE) and specific measurement conditions are met.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If DL-RS update frequency is reduced to lower overhead, then system overhead is reduced, but pathloss calculation accuracy deteriorates
Solution Approach 1:
The patent applies dynamics by making the DL-RS update frequency adaptive rather than fixed. The network dynamically adjusts the update frequency based on channel conditions, terminal mobility, and service requirements. When channel conditions are good or terminal is stationary, update frequency is reduced to lower overhead. When channel conditions deteriorate or terminal moves quickly, update frequency is increased to maintain pathloss calculation accuracy. This dynamic adjustment resolves the contradiction between overhead reduction and accuracy maintenance.
Solution Approach 2:
The patent changes the parameter of DL-RS update frequency based on different operating conditions. By adjusting this parameter dynamically according to channel quality indicators, terminal speed, and service type, the system optimizes the balance between overhead and pathloss accuracy. Different parameter configurations are applied in different scenarios to resolve the fundamental trade-off.
2Measurement precision
If DL-RS update frequency is increased to improve pathloss accuracy, then pathloss calculation accuracy is improved, but system overhead increases
Solution Approach 1:
The system dynamically adjusts DL-RS update frequency based on real-time channel conditions and terminal state. Instead of using a fixed high update frequency that always ensures accuracy but incurs high overhead, the system adapts the frequency to match actual needs. When accuracy requirements are high (e.g., fast mobility), frequency is increased. When requirements are lower, frequency is reduced, thus resolving the contradiction.
Solution Approach 2:
The network performs preliminary assessment of channel conditions and terminal mobility characteristics to determine appropriate DL-RS update frequency before actual pathloss calculation. By predicting future channel states and pre-configuring update frequencies, the system avoids unnecessary updates while ensuring accuracy when needed, thus reducing overhead while maintaining precision.
3Measurement precision
If pathloss calculation accuracy is improved through frequent DL-RS updates, then transmission power control accuracy is improved, but system complexity increases
Solution Approach 1:
The patent implements dynamic adjustment of DL-RS update frequency to match actual transmission power control requirements. Instead of continuously updating at maximum frequency, the system adapts the update rate based on channel stability and power control needs. This dynamic approach maintains accurate power control when necessary while reducing system complexity through fewer updates during stable conditions.
Solution Approach 2:
The system changes the operational parameters of DL-RS updates based on measured channel conditions and power control performance requirements. By adjusting parameters such as update frequency and reference signal density according to actual needs, the system achieves accurate power control without unnecessarily increasing complexity. Different parameter sets are applied in different operational modes.
Data Source
AI summary
A terminal according to an aspect of the present disclosure includes a receiving section that receives a pathloss reference signal, and a control section that calculates a pathloss for transmission power control on the basis of layer 1 (L1)-reference signal received power (RSRP) for the pathloss reference signal when the pathloss reference signal is updated by a media access control-control element (MAC CE), and a measurement condition is met. According to an aspect of the present disclosure, the pathloss can be appropriately calculated.