Reconfigurable Parallel Turbo Decoder Design for Multiple High-Mobility 4G Systems

For high-mobility 4G applications of LTE-A and WiMAX-2 systems, this paper presents a dual-standard turbo decoder design with the following three techniques. 1) Circular parallel decoding reduces decoding latency and improves throughput rate. 2) Collision-free vectorizable dual-standard parallel interleaver enhances hardware utilization of the interleaving address generator. 3) One-bank extrinsic buffer design with bit-level extrinsic information exchange reduces size of the extrinsic buffer compared with the two-bank extrinsic buffer design. Furthermore, a multistandard turbo decoder chip is fabricated in a core area of 3.38 mm by 90 nm CMOS process. This chip is maximally measured at 152 MHz with 186.1 Mbps for LTE-A standard and 179.3 Mbps for WiMAX-2 standard.