Device positioning

A network node comprising at least one processing core, at least one memory including computer program code, the at least one memory and the computer program code being configured to, with the at least one processing core, cause the network node at least to:

• define a first mobile device as a target user equipment and at least one second mobile device as an anchor user equipment;
• transmit to each defined anchor user equipment a sidelink positioning reference signal configuration comprising a constraint set, the constraint set comprising at least one constraint, each of the at least one constraint being based on at least one of:
• a location of the anchor user equipment, a time instant, or a time duration, and
• participate in determining a location of the target user equipment based at least partly on results of measurements of sidelink positioning reference signals at the target user equipment and the anchor user equipment.

A method comprising:

• receiving in user equipment from a wireless network node, or determining autonomously in the user equipment, a sidelink positioning reference signal configuration comprising a constraint set, the constraint set comprising at least one constraint, each of the at least one constraint being based on at least one of:
• a location of the user equipment, a time instant, or a time duration;
• determining, in the user equipment, whether at least one constraint in the constraint set is satisfied, and
• responsive to the at least one constraint in the constraint set being satisfied, transmitting, from the user equipment to a mobile device a first sidelink positioning reference signal and/or receiving a second sidelink positioning reference signal from the mobile device in the user equipment.