Disclosed is a signal transmission method in a mobile communication system. Unequal error protection (UEP) ratios are determined so that the bits may have different received qualities according to the weights of the bits. The bits are repeated by a bit sequence repeater (210) according to the determined UEP ratios to generate a repeated bit sequence having a predetermined number of bits. The generated repeated bit, sequence is interleaved by an interleaver (220) and the interleaved bit sequence is symbol-mapped by a symbol-mapper (230) to generate a transmission symbol sequence, and the generated transmission symbol sequence is transmitted by the transmitter to a receiver. Furthermore, also a corresponding signal reception method, a corresponding signal transmitter and a corresponding signal receiver are disclosed.