Apparatus and method for symbol combining in a mobile communication system

An apparatus and method for soft-combining demodulated symbols in a mobile communication system. In the mobile communication system, a transmitting apparatus modulates symbols in different modulation schemes and a receiving apparatus demodulates the modulation symbols in correspondence with the modulation schemes. The soft symbol combining apparatus includes an RWF calculator, an RWF controller, and a soft symbol controller. The RWF calculator calculates an energy of a modulation symbol from each of the modulation schemes and determines relative ratios of the energies to be RWFs for the modulation schemes. The RWF controller multiplies soft metrics of the demodulated soft symbols by the RWFs. Finally, the soft symbol controller combines the multiplied soft metrics.