Communications and Network, 2013, 5, 136-139
http://dx.doi.org/10.4236/cn.2013.53B2026 Published Online September 2013 (http://www.scirp.org/journal/cn)
A Joint User Selection and Resources Optimization
Scheduling Algorithm for CoMP
Xincheng Zhong, Weihai Li, Yuqin Lv
School of Electronic Engineer, Beijing University of Posts and Telecommunications, Beijing, China
Email: zxc072433@gmail.com
Received April, 2013
ABSTRACT
Coordinated Multi-point (CoMP) transmission technology is one of the key techniques in LTE-Advanced, Which can
share the channel and data information in multiple cells, and optimize the whole system performance. In order to opti-
mize the average sector throughput and improve the fairness of resource scheduling, a scheduling algorithm based on
the resource is mainly investigated. In this algorith m, users in the netwo rk are classified fi rstly and then we combine the
fixed resources division and flexible scheduling. System level simulation platform is set up to validate the algorithm
and the results turn out that the average throughput is better compared with the traditional scheme.
Keywords: CoMP; User Selection; Resource Scheduling; System Level Simulation
1. Introduction
As one of the key techniques in LTE-Advanced, CoMP
is discussed in detail in the 3GPP. With its effect in re-
ducing interference between neighboring cells, optimi-
zating the whole system performance of multiple cells
and expanding the coverage of high data rate, people pay
more and more attention to it[1]. Its basic principle is
through the coordination of different base transceiver
stations (BTS), the interference can be converted to use-
ful signal. According to the information can be shared
among multiple transport nodes or not, CoMP technol-
ogy can be divided into the joint processing (JP) and
beam forming[2].
Resource scheduling algorithm for JP is a research
hotspot in CoMP to further improve the system per-
formance[3,4], as the CoMP system requires the alloca-
tion of resources in multi-point coordinated cells, and
single-cell resource scheduling can’t meet the require-
ment of the system scheduling, we need to design sched-
uling algorithm which can consider interference between
adjacent BTSs. The author in [5] has investigated a us-
er-centric scheduling scheme in downlink channel to
provide coordination for majority of users, so as to im-
prove the average throughput, but the increasing of the
system complexity was not consid ered. In [6], centralized
control in CoMP system was researched and the author
proposed to use the MAC layer to transport the informa-
tion of channel status, so as to reduce the system com-
plexity. In order to avoid the waste of resources and re-
duce the scheduling complexity, collision avoidance re-
sources scheduling scheme for CoMP was proposed in
[7].
In this paper, the scheduling scheme based on re-
sources for single-user multi-input multi-output (CoMP-
SU-MIMO) is researched, which improves the traditional
scheme of dividing the users into cell-edge users and
cell-center users by the SINR values[8], and 2 or 3 sec-
tors coordination is added to reduce the waste of re-
sources, at the same time, on the basis of the scheme to
divide the frequency into fixed two parts, resources op-
timization is considered in one part to ensure profit both
edge and center users. We also set up a system level si-
mulation platform and the simulation results also verify
the effectiveness of the proposed algorithm.
The rest of paper is organized as follows: In section II,
the system model of JP in CoMP is described. Section III
introduces the specific scheduling algorithm and the si-
mulation results are showed in section IV. Then conclu-
sions are drawn in section V.
2. CoMP JP System Model
The downlink of a cellular network with M hexagonal
cells is considered and each cell is partitioned into 3 sec-
tors with K active users served within the coverage of
each sector. The total number of BTSs in the system is M.
Each BTS which corresponds to one sector is equipped
with Nt transmit antennas, while each user has Nr receive
antennas. We assume each three adjacent sectors as a
cluster[9], show as in Figure 1.
1) Considering the serving BTS m, and user k in clus-
ter c severed in the CoMP mode, the received signal is
given as:
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