The invention relates to a centrifugal fan impeller having an axis of rotation and comprising one or more modules. Dry air is brought to the dryer through a beam located in front of the paper web in the machine direction, in which dryer the air is directed by means of nozzles arranged in the beam into a throat between the drying cylinder and the paper web mainly to intensify the drying effect. The multiplexer also includes a plurality of second switches each of which is coupled to a respective one of the second conductors. The stored key characteristics of the packet are then used by the network processing complexes in its further processing of the frame. The conjugate gradient algorithm is based on the received signal y, the matrix \u015c, the matrices F1 and F2, the predicted channel estimate hpred, and a previous channel estimate h1.