Summary: | 碩士 === 國立臺灣大學 === 電信工程學研究所 === 100 === In cellular system, the unavoidable inter-cell interference would dramatically degrade the system throughput when frequency reuse of one is considered, and then we can''t ignore them anymore as traditional single cell,especially for cell-edge users. Coordinated multi-point (CoMP) transmission/reception is one of candidate techniques in LTE-Advanced (LTE-A) system to solve this problem and improve throughput. And Coordinated scheduling (CS) is one kind of schemes in CoMP. In this scheme, backhauls across BSs can transmit signaling and scheduling information. It means that BSs don’t have to transmit data across backhaul anymore in CS. Here, we propose coordinated scheduling algorithms under the multi-cell multi-input multi-output (MIMO) downlink system, and there are no additional backhaul
between coordinated cells required for scheduling.
In this thesis, we focus on cell-edge users, and then the user scheduling are designed by combining with the physical algorithms to improve performance with the consideration of inter-cell interference. In general, users whose channels are nearly orthogonal are suitable to be scheduled at the same time. Due to MIMO channel setting, our proposed scheduling employs the chordal distance as the distance metric between MIMO channels, which could serve as
the angle between two channels. In the simulation, we compare with several existing scheduling strategies under two antenna settings, which one is that the number of receiver antenna is larger than the received data streams of
a user, and the other is that the number of receiver antenna is equal to thereceived data streams. The former has additional degree of freedom, but the latter does not have. When receiver has additional degree of freedom
to suppress interference, we could only adopt the proposed norm-oriented scheduling strategy. When the receiver does not have the additional degree of freedom, the scheduling needs to further consider the chordal distance in addition to channel norm.
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