Turbo codes are extensively used in wireless communication systems and have been adopted as the channel coding scheme for next generation cellular standards. The complexity associated with the decoding process is an important issue. In this paper, we propose an adaptive Soft Output Viterbi Algorithm (adSOVA) based turbo decoder which is proved to reduce complexity without experiencing a degradation in error correction performance. The proposed adSOVA is evaluated in a long term evolution (LTE) downlink scenario and compared with the SOVA and the Max-Log-MAP algorithms. Simulation results show that a complexity reduction of 40% can be achieved with respect to the conventional SOVA with no BLock Error Rate (BLER) degradation
