Abstract：The development of wireless traffic toward high data rates and high dynamism has brought great challenges to traditional cellular networks. Heterogeneous networks with small base-station sleeping are an effective solution to this problem, which balances service quality and network energy consumption. The scheduling of small base-stations should be based on the status information about the channel between users and small base-stations. However, once the small base-stations are turned off, they switch to the sleeping mode, thus the system is unable to obtain the aforementioned information. To solve this problem, this paper presents a periodical opening mechanism for small base-stations: the system periodically opens the small base-stations to obtain channel information between the users and the small base-stations; once the users send an access request via the macro base-stations, the system makes the correspondent decision on the basis of the channel information obtained when the small base-stations were open at the last time. The design of the opening cycle is a key factor influencing the effect of this mechanism. This paper divides the total energy consumption of the network into two parts, the energy consumption for periodical opening of small base-stations and the energy consumption for user service, and works out an optimal cycle design solution balancing the two parts and minimizing the total energy consumption.
蔡世杰, 肖立民, 王京, 周世东. 以节能为目标的小基站周期性开启研究[J]. 清华大学学报（自然科学版）, 2016, 56(1): 111-116.
CAI Shijie, XIAO Limin, WANG Jing, ZHOU Shidong. Research on periodical opening of small base-stations for energy conservation. Journal of Tsinghua University(Science and Technology), 2016, 56(1): 111-116.
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