IEEEJOURNALONSELECTEDAREASIN方案.PDFVIP

IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS, VOL. 29, NO. 6, JUNE 2011 1225 Adaptive Interference Management of OFDMA Femtocells for Co-Channel Deployment Ji-Hoon Yun, Member, IEEE, and Kang G. Shin, Fellow, IEEE Abstract —Femtocell technology has been drawing considerable attention as a cost-effective means of extending cellular coverage and enhancing capacity as well as realizing its potential, when combined with orthogonal frequency-division multiple access (OFDMA), for improved indoor broadband wireless services. However, under the expected co-channel deployment of femto- and macro-cells, femtocells may incur high uplink interference to macrocells, and vice versa. To mitigate this interference, we propose a distributed and self-organizing femtocell manage- ment architecture, called the Complementary TRi-control Loops (CTRL), that consists of three control loops to determine (1) maximum transmit power of femtocell users based on the fed- back macrocell load margin for protection of the macrocell uplink (a) Macrocell users’ SINR under a varying communications; (2) target signal to interference plus noise ratios number of femtocells (SINRs) of femtocell users to reach a Nash equilibrium; and (3) instantaneous transmit power of femtocell users to achieve the target SINRs against bursty interference from other nearby users. CTRL requires neither special hardware nor change to the radio resource management (RRM) of existing macrocells, thus facilitating non-disruptive (hence seamless) penetration of femtocells. Also, CTRL guarantees convergence in the presence of environmental changes and delayed feedb