An arrangement for coding digital symbols and transmitting them through at least two antennas. A coder reads at least two symbols belonging to the same transmission block and forms channel symbols of the symbols of the transmission block by means of a block code. The coder multiplies at least one symbol belonging to the transmission block by a first nonzero weighting coefficient and at least one symbol belonging to the transmission block by a second nonzero weighting coefficient, and the division ratio of the first and second weighting coefficients differs from values ±1, ±j and ±1/sqrt(2). The thus formed channel symbols are transmitted to the radio path through the antennas.