A radio base station node (20) of a telecommunications network comprises a baseband transmitter (22) and plural radio frequency (RF) paths (24) between the baseband transmitter (22) and an antenna system (30). A measurement entity (32) is provided, preferably near the antenna system (30), for making a measurement or comparison of a time of detecting of a power modulation for each of plural RF transmission paths (24), e.g., a time of detecting of a power modulation for a first of the plural RF transmission paths and a time of detection of a power modulation for a second of the plural RF transmission paths. A transmission timing adjustment unit (34) uses the power modulation measurement or comparison for adjusting timing of transmission of signals for the plural RF transmission paths for obtaining a desired time alignment for the plural RF transmission paths.