On LTE coding scheme inefficiency & potential improvement

Coding and decoding schemes are critical to the performance in wireless communication system. In Current coding scheme of LTE system, each transport block (TB) is segmented into several code blocks (CBs) which can be coded and decoded individually. If one of the CBs in a TB fails in decoding, the whole TB is required to be retransmitted. Channel estimation is very crucial for the correctness of the decoding. In LTE, the demodulation reference signal (DM-RS) used for channel estimation, are unevenly arranged in resource block pair (RBP). We first show how the arrangement of DM-RS can impair channel estimation of some CBs, which ultimately results in the inefficiency of the coding scheme. To solve the problem, we propose a design by commandeering the decoded data with higher accuracy channel estimation as reference signals to help to estimate the channel of the part which lacks of DM-RS. The performance is evaluated via simulations.