A circuit of a node in a radio network and method for transit time measurement between a first node and a second node of a radio network is provided. A frame is transmitted by the first node, wherein the frame requires an acknowledgment of reception by the second node. A first point in time of the transmission of the frame is established by the first node by a time counter. The frame is received by the second node at a second point in time. The acknowledgment is transmitted by the second node to the first node at a third point in time, wherein the third point in time depends on the second point in time by a predetermined time interval between the second point in time and the third point in time. A fourth point in time is established by the first node by the time counter when the acknowledgment is received. The transit time or the change in transit time is determined from the first point in time established by the time counter and from the established fourth point in time and from the predetermined time interval.