Methods and apparatus for supporting positioning in idle or inactive mode

• Main Authors: Ferrari, Lorenzo, Prakash, Rajat, Lin, Yih-Hao, Manolakos, Alexandros, Sun, Jing, Yerramalli, Srinivas, Zhang, Xiaoxia
• Format: Patent
• Language: English
• Published: 13.08.2024
• Subjects: ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; TRANSMISSION; TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHICCOMMUNICATION; WIRELESS COMMUNICATIONS NETWORKS

A user equipment (UE) transmits reference signals for positioning while in Idle or Inactive state. While in a connected state, the UE is pre-configured with Sounding Reference Signal (SRS) resource configuration including at least one of timing adjustment (TA) and an uplink (UL) transmission spatial filter. The UE transmits positioning SRS while in Idle or Inactive mode based on the pre-configuration. The TA and UL transmission spatial filter may be updated by a serving base station using control signals or a paging message received by the UE while in in Idle or Inactive mode. The validity of the TA and UL transmission spatial filter may be monitored using expiration timers or a relative position change threshold. The reference signals transmitted may be based on a UE may Physical Random Access Channel (PRACH), which is insensitive to TA changes. A long sequence PRACH may be used for improved positioning accuracy.