  Recently, a new class of error-control codes, the polar codes, have attracted
much attention. The polar codes are the first known class of capacity-achieving
codes for many important communication channels. In addition, polar codes have
low-complexity encoding algorithms. Therefore, these codes are favorable
choices for low-complexity devices, for example, in ubiquitous computing and
sensor networks. However, the polar codes fall short in terms of finite-length
error probabilities, compared with the state-of-the-art codes, such as the
low-density parity-check codes. In this paper, in order to improve the error
probabilities of the polar codes, we propose novel interactive coding schemes
using receiver feedbacks based on polar codes. The proposed coding schemes have
very low computational complexities at the transmitter side. By experimental
results, we show that the proposed coding schemes achieve significantly lower
error probabilities.
