The invention relates to a method for encoding a number of feedback information messages in a mobile radio communications system using carrier aggregation, the method comprising: encoding the number of feedback information messages by a set of codewords, where each feedback information message can be of at least a first kind or a second kind. The method is distinguished by that for at least one feedback information message there is at least one codeword corresponding to information of the first kind and at least one codeword corresponding to information of the second kind, wherein the modulation symbol of one of said at least one codeword corresponding to information of the first kind and the modulation symbol of one of said at least one codeword corresponding to information of the second kind have a maximum distance. The invention also relates to a mobile terminal and radio basestation for a communications system.