The effectiveness of the convolutional code increases with the constraint length of the code. Unfortunately the decoding complexity of Viterbi algorithm grows exponentially with the constraint length. In this paper we propose a suboptimal decoding method based on the calculation of the maximum weight basis of the convolutional code. We extend the algorithm to incorporate the ideas of list decoding method. The complexity of the algorithm grows only quadratically with the constraint length and the performance of the algorithm is comparable to the optimal Viterbi decoding method.