Abstract: The invention relates to a sensor monitoring system comprising at least one sensor (101, 102, 103) and a processing unit (150), wherein the sensor is arranged to transmit during a plurality of successive time periods data items to the processing unit and the processing unit is arranged to receive the data items from the said at least one sensor, the processing unit being further arranged for: determining for at least some time periods from the said plurality of successive time periods a number of corresponding data items; comparing between the at least some time periods the number of the corresponding data items; deducing for the at least some time periods a parameter associated with a variation in the number of data items per said some time periods. The invention further relates to a processing unit, and a method and a computer program for sensor monitoring.

Abstract: Signal data from a sensor is stored in a storage device. The signal data is accessed by means access request that includes an identification of a base signal that may indicate the signal data from said sensor and an identification of a derivation to obtain a requested signal from the base signal. An interface extracts the identifications of the base signal the derivation. The interface tests whether stored signal data obtained from the base signal by said derivation is available in the storage device, and if so it returns the stored signal data in response to the access request via the interface. If not signal data is derived from further stored signal data by at least one signal processing operation identified in the derivation.

Abstract: Signal data from a sensor is stored in a storage device. The signal data is accessed by means access request that includes an identification of a base signal that may indicate the signal data from said sensor and an identification of a derivation to obtain a requested signal from the base signal. An interface extracts the identifications of the base signal the derivation. The interface tests whether stored signal data obtained from the base signal by said derivation is available in the storage device, and if so it returns the stored signal data in response to the access request via the interface. If not signal data is derived from further stored signal data by at least one signal processing operation identified in the derivation.

Abstract: The invention relates to a sensor monitoring system comprising at least one sensor (101, 102, 103) and a processing unit (150), wherein the sensor is arranged to transmit during a plurality of successive time periods data items to the processing unit and the processing unit is arranged to receive the data items from the said at least one sensor, the processing unit being further arranged for: determining for at least some time periods from the said plurality of successive time periods a number of corresponding data items; comparing between the at least some time periods the number of the corresponding data items; deducing for the at least some time periods a parameter associated with a variation in the number of data items per said some time periods. The invention fur they relates to a processing unit, and a method and a computer program for sensor monitoring.