Joint Network Channel Fountain Schemes for Machine-Type Communications Over LTE-Advanced

Machine-type communications (MTC) also known as machine-to-machine (M2M) communications over long-term evolution-advanced (LTE-A) networks with ubiquitous coverage and global Internet working is expected to constitute a significant part of the Internet of Things (IoT) paradigm. However, there are paramount challenges and active research activities to accommodate M2M communications over LTE-A network without sacrificing the quality of human-based services. Among them the performance of M2M communications in LTE advanced relay network has not been fully investigated yet. In particular, LTE/LTE-A uses turbo codes as the forward error correction (FEC) mechanism in the physical layer. Since turbo codes are fixed rate codes, an automatic repeat request (ARQ) is sent to the sender when the receiver fails to recover complete packet that results in packet failure and waste of radio resources. In this paper, to combat the detrimental effects of wireless fading channel, we propose a set of joint network and fountain coding (JNFC) schemes for reliable uplink transmission between M2M devices and evolved NodeB (eNB). Specially, we consider clustered heterogeneous M2M networks, where cluster heads (CHs) transmit to eNB directly or by the help of relays. Numerical results are presented to demonstrate the performance of the proposed schemes over type I and type II relay-enhanced LTE-A networks. It shows that in type I relay enhanced networks, JNFC with space time block codes (JNFC-STBC) outperforms the direct transmission with relays (DTRs) and in type II enhanced networks, JNFC with robust soliton distribution (JNFC-RSD) outperforms JNFC with random linear network coding (JNFC-RLNC) in a variety of metrics.