  This paper deals with the improvement of energy efficiency in wireless sensor
networks (WSN).Taking into consideration the power saving problem which is of
crucial importance when the sensors are supplied by a limited power source,
this paper proposes a method that optimizes as much as possible the
transmission power of the sensors. Under the assumption of perfect channel
between the Base Station (BS) and the Sensor Nodes (SN's) and with sufficient
power resources at the BS, transferring the effort of transmission power to the
BS will not be a peculiar issue. This paper proposes a method that reduces the
transmitted data at the SN's and compensate this by requesting the variance of
the measured value form predicted values. Furthermore, a request management
algorithm (RMA) is developed to reduce the amount of requested data based on
consecutive successive predictions. The result of this method reveals a major
impact on reducing the transmission power at the SN's. Keywords: Wireless
Sensor Networks, Data Reduction, Time Series Forecasting, Artificial Neural
Networks.
