Use of previously buffered state information to decode in an hybrid automatic repeat request (H-ARQ) transmission mode

A decoder comprising:

• a buffer operable to store forward or reverse state information that is associated with a previously-transmitted packet;
• and
• convolutional-turbo-code (CTC) decoding logic operatively associated with the buffer, the CTC decoding logic having an unknown starting state in which trellis states of the CTC decoding logic have a same initial probability, and operable to:
• receive a packet retransmitted in accordance with a hybrid automatic repeat request (H-ARQ) communication mode;
• read the forward or reverse state information stored in the buffer that is associated with the previously-transmitted packet;
• and
• assign, based on the buffered forward or reverse state information, a starting probability to one of the trellis states of the CTC decoding logic to attempt to decode the packet, the assigned starting probability different from the initial probability.

A system comprising:

• a receiver operable to receive packets in a hybrid automatic repeat request (H-ARQ) communication mode;
• a buffer operable to store forward or reverse state information associated with received packets;
• and
• a convolutional-turbo-code (CTC) decoder having an unknown starting state in which trellis states of the CTC decoder have a same initial probability, the CTC decoder operable to:
• determine that one of the packets received via the receiver is a retransmitted packet;
• read, responsive to determining that the packet is a retransmitted packet, forward or reverse state information associated with a previously-transmitted packet from the buffer;
• assign, based on the forward or reverse state information associated with the previously-transmitted packet, a starting probability to one of the trellis states of the CTC decoder, the assigned starting probability different from the initial probability;
• and
• decode, via the CTC decoder and based on the assigned starting probability, the retransmitted packet.