An Uplink Non-Orthogonal Multiple Access Method Based on Frozen Bit Patterns of Polar Codes

In this letter, we propose a low-complexity uplink non-orthogonal multiple access (NOMA) scheme based on polar codes. The proposed scheme, called polar coding-based NOMA (PC-NOMA), relies on the separation of user signals transmitted in the same physical resources using binary-valued patterns embedded in the frozen bit locations of polar codes. By means of frozen bit patterns unique to each user, the superimposed user signals are separated at the receiver by an interference-cancelation algorithm and a polar decoder. We demonstrate that the proposed scheme performs well even when the received powers of the multiplexed users are not significantly distinct.