Turbo Decoder Applications

The WiMedia Alliance is a non-profit organization that promotes and certifies ultra-wide band (UWB) technologies. In version 1.5 of its physical layer, the WiMedia standard adopted LDPC codes for high data rates (payload throughputs of up to 1 Gbit/s). For lower rates, convolutional codes are used. The standard defines two block lengths: 1200 and 1320. The long blocks are obtained by a re-encoding of the short blocks with a rate 10/11 LDPC code. These additional parity bits are transmitted on the guard tones of an OFDM symbol for throughputs of 640 Mbit/s and above. The receiver, however, is allowed to ignore these 120 additional parity bits for decoding.