2012/02/07 by Ansuman Adhikary, Giuseppe Caire, Adhikary, Ansuman +1 · 1 citation
Computer Science · Engineering · Mathematics · #Advanced MIMO Systems Optimization #Cooperative Communication and Network Coding #FOS: Computer and information sciences #Information Theory (cs.IT) #Satellite Communication Systems #Wireless Communication Networks Research #cs.IT #math.IT
paper · pdf · doi:10.48550/arxiv.1202.1449
Submitted to the 1st International Workshop on Small Cell Wireless Networks (SmallNets), ICC 2012
arxiv created 2012/02/07 · openalex publication_date 2012/02/07 · arxiv updated 2012/02/08 · openalex created_date 2022/10/02 · openalex updated_date 2026/07/28
We study a two-tier macrocell/femtocell system where the macrocell base station is equipped with multiple antennas and makes use of multiuser MIMO (spatial multiplexing), and the femtocells are "cognitive". In particular, we assume that the femtocells are aware of the locations of scheduled macrocell users on every time-frequency slot, so that they can make decisions on their transmission opportunities accordingly. Femtocell base stations are also equipped with multiple antennas. We propose a scheme where the macrocell downlink (macro- DL) is aligned with the femtocells uplink (femto-UL) and, Vice Versa, the macrocell uplink (macro-UL) is aligned with the femtocells downlink femto-DL). Using a simple "interference temperature" power control in the macro-DL/femto-UL direction, and exploiting uplink/downlink duality and the Yates, Foschini and Miljanic distributed power control algorithm in the macro- UL/femto-DL direction, we can achieve an extremely attractive macro/femto throughput tradeoff region in both directions. We investigate the impact of multiuser MIMO spatial multiplexing in the macrocell under the proposed scheme, and find that large gains are achievable by letting the macrocell schedule groups of co-located users, such that the number of femtocells affected by the interference temperature power constraint is small.