채널 추정 정확도 향상을 위한 셀프리 대규모 안테나 시스템에서의 서브채널 자원할당 기법

초록

As wireless networks become increasingly dense, interference has become a major obstacle to spectral efficiency (SE) and scalable network operation. Cell-free massive MIMO (CF-mMIMO) alleviates inter-cell interference by enabling cooperative transmission among distributed access points (APs). However, practical systems adopt dynamic cooperation clustering (DCC) for scalability, which causes inter-AP cluster interference (IACI)—a critical bottleneck in dense deployments. To address this issue, we propose a subchannel-aware CF-mMIMO framework that dynamically partitions bandwidth and integrates frequency-domain separation into the clustering process. The proposed method effectively suppresses IACI and pilot contamination, yielding up to a 16% improvement in achievable rate. These results highlight the importance of subchannel allocation for scalable CF-mMIMO operation in ultra-dense networks.