NTN PRACH Timing Advance Pre-Compensation With Timing Margins

The UE performs preliminary timing advance calculation based on satellite position and propagation delay before the actual PRACH transmission. This preliminary action allows the UE to pre-adjust its timing, but the patent introduces a timing margin to prevent overcompensation that would cause reception outside the PRACH window.

The patent introduces a timing margin as a cushioning mechanism to prevent overcompensation. This timing margin acts as a safety buffer that absorbs potential timing errors in the propagation delay calculation, ensuring that even if the calculated timing advance is slightly inaccurate, the PRACH signal will still be received within the valid window.

The patent segments the UE population into two groups: those with auto-synchronization capability (GNSS) and those without. Each group is assigned distinct PRACH configurations optimized for their specific capabilities. This segmentation allows the network to tailor resources and parameters appropriately for each group, improving overall detection performance.

Different PRACH configuration parameters (such as timing advance values, frequency offsets, and resource allocations) are applied locally to each UE group based on their specific synchronization capabilities. This local quality approach ensures that each group receives the most appropriate configuration for its characteristics rather than a one-size-fits-all solution.