Abstract: The invention relates to a method and a radio device for detecting a movement of at least one receiver, wherein the radio signals are sent from at least one stationary transmitter to the at least one receiver and the received signals are evaluated for determining a movement. The radio signals are designed as a specified bit sequence modulated onto a high-frequency carrier and are demodulated by the receiver to form a receiving sequence that is correlated to determine correspondence with the specified bit sequences stored as a reference sequence. Dependent on the correspondence or errors that can be determined by the correlation, quality indicators for the receiving field strength of the received radio signals are determined, wherein the radio signals having the specified bit sequence are sent from the transmitter having at least two different transmission powers in a series.

Abstract: A transmission system for a measurement device on a coordinate positioning apparatus comprises a station (18) mounted on the measuring device (10) and a station (20) mounted on the coordinate positioning apparatus (22), wherein the stations communicate with each other using a spread spectrum radio link, for example frequency hopping. The station on the probe sends a regular signal and on receiving the signal the station on the coordinate positioning apparatus synchronises its clock and sends an acknowledgement signal. Measurement data is either sent in the regular signal or in a measurement event driven signal.