Decoding of Quasi-Cyclic Codes up to A New Lower Bound on the Minimum   Distance
  A new lower bound on the minimum Hamming distance of linear quasi-cyclic codes over finite fields is proposed. It is based on spectral analysis and generalizes the Semenov- Trifonov bound in a similar way as the Hartmann-Tzeng bound extends the BCH approach for cyclic codes. Furthermore, a syndrome-based algebraic decoding algorithm is given. 
Alexander Zeh, San Ling
cs.IT math.IT