Measurement time ranges for timing advance (TA) validation for small data transmission (SDT)

A wireless device operable in a wireless communication network that supports small data transmission (SDT), the wireless device comprising:

• processing circuitry;
• an antenna configured to communicate wireless signals with a network node of the wireless communication network, the network node providing a serving cell;
• radio front-end circuitry connected to the antenna and to the processing circuitry, the radio front-end circuitry configured to condition signals communicated between the antenna and the processing circuitry;
• the processing circuitry configured to:
• obtain, at a first time (T1), information about one or more pre-configured resources used for the SDT, the information including a value of a timing advance (TA);
• determine a validity of a first measurement of the serving cell and of a second measurement of the serving cell, wherein determining the validity comprises:
• determining whether the first measurement was obtained within a first time range that is based on the first time, and that is based on a first set of one or more parameters comprising one or more of:
• a periodicity (Trs) of a reference signal (RS) used for obtaining the first measurement, and a relation between the periodicity and a configured discontinuous reception (DRX) cycle length (TDRX) of the serving cell;
• and
• determining whether the second measurement was obtained within a second time range that is based on a second time (T2) representing a start time of a next SDT occasion, and that is based on a second set of one or more parameters comprising one or more of:
• a periodicity (Trs) of a reference signal (RS) used for obtaining the second measurement, and a relation between the periodicity and a configured discontinuous reception (DRX) cycle length (TDRX) of the serving cell;
• validate the TA when the first measurement and the second measurement are valid;
• and
• perform, while the wireless device is operating in a low activity radio resource control (RRC) state, a SDT uplink transmission to the network node using the validated TA.