Abstract: The invention relates to the selection of an antenna in a receiver of a mobile radio station which forms part of a time-multiplexed radio communication system. The signal strength of each antenna is measured in each time slot which immediately precedes the time slot intended for the station concerned, and the antenna selection is effected in dependence on the measured signal strengths. In order to eliminate the risk of unsuitable antenna selection as a result of momentary falls in signal strength, the signal strength for each antenna is measured on several occasions during the time slot in which the measurements take place. The signal-strength values for each antenna are thereafter combined linearly, so as to form a suitability measurement. The antenna having the highest suitability measurement is selected for the next arriving time slot.

Abstract: A method for compensating for non-linearities in an end amplifier (F) having a given transfer function H.sub.R, H.sub..phi. for amplitude and phase respectively and included in a radio transmitter of quadrature type for linear, digital modulation, and in which table look-up units (ST, CT) store the digital sine and cosine values (I(t,.alpha.), Q(t,.alpha.)) of the quadrature components determined by a given signal vector .alpha.. According to the method of values of the transfer functions H.sub.R, H.sub..phi. for the quadrature modulated radio signals r(t,.alpha.) are calculated by addressing memory units (MH1, MH2) which store a number of values of H.sub.R and H.sub..phi.. The sine and cosine values of the addressed values of H.sub.R and H.sub..phi. are also formed. The thus calculated values are multiplied by the stored digital values in the table look-up units (ST, CT) and by the inverted value of H.sub.R. As a result, new modified values i(t,.alpha.), q(t,.alpha.