Satellite Access Network Measurement Scaling Factor
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The high Doppler shift in Non-Terrestrial Networks (NTN) due to the fast movement of Low Earth Orbit (LEO) satellites complicates satellite/cell measurements for user equipment (UE), increasing hardware and software complexity and costs.
Innovation Solution
Implementing time-division multiplexing (TDM) schemes that use a scaling factor to extend the measurement period, allowing UE to perform measurements on different satellites separately rather than simultaneously, and applying measurement restrictions to avoid conflicts, thereby reducing the burden on UE resources.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If satellite/cell measurements are performed in NGSO satellite-based NTN, then satellite communication capability is achieved, but UE processing burden and hardware/software complexity increase due to large Doppler shifts
Solution Approach 1:
The patent segments the measurement process by introducing a measurement timing configuration (MTC) that divides satellite measurements into distinct time slots. The MTC parameters (period, offset, duration) create separate measurement windows for different satellites, allowing the UE to process one satellite at a time rather than simultaneously handling multiple satellites with large Doppler shifts, thus reducing processing burden while maintaining satellite communication capability
Solution Approach 2:
The patent implements periodic measurement opportunities through the MTC period parameter, which defines regular intervals for satellite measurements. This periodic structure allows the UE to allocate dedicated time resources for Doppler compensation and measurement processing, reducing the continuous processing burden while maintaining accurate satellite measurements across different orbital positions
2Measurement precision
If Doppler effect is compensated for in satellite measurements, then measurement accuracy is improved, but UE hardware and software requirements become more complex and expensive
Solution Approach 1:
The patent applies preliminary Doppler compensation by providing the UE with satellite ephemeris data and orbital parameters in advance. The network configures MTC parameters that pre-account for expected Doppler shifts based on satellite trajectories, allowing the UE to apply predetermined compensation algorithms rather than requiring complex real-time Doppler tracking hardware and software
Solution Approach 2:
The patent introduces the measurement timing configuration (MTC) as an intermediary mechanism that mediates between the satellite's high-speed motion and the UE's measurement capabilities. The MTC parameters (period, offset, duration) act as a coordination layer that schedules measurements when Doppler effects are more manageable, reducing the complexity of direct real-time Doppler compensation while maintaining measurement accuracy
3Productivity
If multiple satellites are measured simultaneously, then satellite selection and handover performance is improved, but UE resource burden increases
Solution Approach 1:
The patent segments the measurement of multiple satellites into distinct time slots defined by the MTC configuration. By dividing the measurement process across different time periods with specific offsets and durations, the UE can systematically measure multiple satellites sequentially rather than simultaneously, reducing resource burden while maintaining the ability to perform satellite selection and handover
Solution Approach 2:
The patent implements dynamic measurement scheduling where the MTC parameters (period, offset, duration) can be adjusted based on satellite orbital positions and measurement requirements. This dynamic configuration allows the network to optimize measurement opportunities for multiple satellites according to their relative positions and Doppler characteristics, enabling efficient satellite handover without requiring the UE to maintain constant high-resource measurement of all satellites
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enables efficient satellite/cell measurements in NTN without significant increases in UE resources, balancing mobility performance and design costs.
Implementation Method 1
One of the challenges in NGSO communications is that the Doppler shift is huge since the NGSO satellites move at a high speed. The Doppler shift of a LEO-600 km network can be up to 24 parts per million (ppm). For example, in the 2 gigahertz (GHz) carrier, the maximum Doppler shift of a LEO satellite can be up to +/â48 kilohertz (kHz).
Data Source
AI summary
Various solutions for satellite access network (SAN) or non-terrestrial network (NTN) measurement with respect to user equipment and network apparatus in mobile communications are described. An apparatus may determine a first number of synchronization signal blocks (SSBs) or SSB-based radio resource management (RRM) measurement timing configurations (SMTCs) overlapped in a time domain. The apparatus may determine a second number of satellites to be measured in each of the SMTCs. The apparatus may calculate a scaling factor according to the first number and the second number. The apparatus may determine a measurement period by applying the scaling factor. The apparatus may perform measurements on the satellites within the measurement period.