Joint Cancellation of Phase Noise and NB-IoT Interference in OFDM System

In the scenario of the coexistence of long term evolution (LTE) system using orthogonal frequency division multiplexing (OFDM) and narrowband Internet-of-Things (NB-IoT), when the in-band model is used, the narrowband interference caused by NB-IoT will seriously degrade the performance of OFDM. Meanwhile, the phase noise (PHN) generated by the local oscillators also reduce the reliability of OFDM transmission. In this letter, an algorithm of jointly eliminating NB-IoT interference and PHN is proposed within the sparse Bayesian learning framework for OFDM system, when the channel noise follows non-Gaussian distribution. An iterative solution is derived after the optimization structure is constructed. Simulation results demonstrate that the gain of proposed method over the conventional methods is approximately 1.5-3.5 dB when the bit error rate is 10 ^-3 .