An anti-overflow control method of state metrics for high throughput Turbo decoder

Since the dynamic range of state metrics is limited due to the finitude of their quantization, it is needed to take an anti-overflow operation in the implementation of Turbo decoder. In traditional methods, plenty of calculations should be done for the anti-overflow protection in a single cycle, which greatly restricts the actual running clock frequency, thus to bring a strong impact on the final decoding throughput. In this paper, a novel anti-overflow method is proposed, to compare with the conventional methods, the proposed method can significantly increase the running clock frequency and achieve higher decoding throughput without losing any decoding performance.