Abstract: A position of a vehicle is determined by outputting position signals by a reception antenna and outputting traveling condition values by traveling condition sensors of a vehicle for determination of an absolute position of the vehicle and outputting an absolute position signal, from the absolute position signal and predetermined reference data of a reference system determining a relative position of the vehicle in the reference system, determining a position quality signal from a comparison of the absolute position signal and a reference position signal, and using the position quality signal for determination of an absolute position of the vehicle.

Abstract: In a method and apparatus for selecting signals from navigation satellites, a selection is performed on signals which are directly or indirectly received from navigation satellites. Since the indirectly received satellite signals result in a false determination of position, they are suppressed. The selection is carried out for a satellite receiver, whose antenna is mounted, for example, in a vehicle in the vicinity of the rear window or the front windshield. A receiving range of the antenna is determined on the basis of the antenna location. Of the received satellite signals, those signals whose satellites are situated within the receiving range of the antenna are separated at this point. The satellites situated within the receiving range are recognized on the basis of the satellite orbits, which are stored, for example, in a storage device of the receiver.

Abstract: A circuit arrangement for scanning optical recording carriers comprises a scanning device, a first control loop for focusing a light beam of the scanning device directed onto the information plane of the recording carrier and a second control loop for guiding the light beam on an information track. The first control loop exhibits a first control amplifier which is supplied with focus error signals and the second control loop exhibits a second control amplifier which is supplied with track error signals. The control amplifiers drive actuators which mechanically guide the scanning device. To compensate for the temperature response of the control gain, controlling elements connected to temperature sensors via gain controllers are arranged in the first and second control loop, which controlling elements temperature-dependently change the gains.