LAA系统在非授权频段上的动态子帧配置策略

doi:10.11959/j.issn.1000-0801.2016193

摘要/Abstract

摘要：

异构网络中动态TDD技术的应用可以有效提高系统吞吐量，改善系统性能。由于受到信令控制等问题的限制，授权频段上往往只是实现传统的7种固定子帧配比之间的动态切换。而非授权频段作为工作在授权频段上LTE系统的一个补充，不用考虑信令控制等问题，可以实现更加灵活的完全动态子帧配置。提出了两种非授权频段上的动态子帧配置算法，并与传统的静态子帧配置进行比较，通过LAA系统级仿真平台验证动态子帧配置算法对系统性能的影响。仿真表明，提出的两种动态子帧配置算法可以有效提升资源利用率，提高系统整体吞吐量。

关键词: 动态子帧配置, LAA, 非授权频段, 系统级仿真

Abstract:

The use of dynamic TDD technology in heterogeneous network can effectively increase the system throughput and improve the performance of the system.Due to the limitation of signaling control and other issues,there is usually a dynamic switching between the traditional seven fixed sub-frame ratios in the licensed bands.But as a complement to the LTE system worked in the licensed bands,the unlicensed bands can achieve a more flexible and complete dynamic sub-frame configuration without considering signaling control and other issues.Two new dynamic sub-frame configuration algorithms in unlicensed bands were proposed and compared with traditional static sub-frame configuration,then the impact of dynamic sub-frame allocation algorithms on system performance was verified by LAA system level simulation platform.The results show that the proposed dynamic sub-frame configuration strategies can effectively improve the resource utilization and the overall system throughput.

Key words: dynamic sub-frame configuration, licensed-assisted access, unlicensed band, system level simulation

姜炜,刘是枭,胡恒,张晨璐. LAA系统在非授权频段上的动态子帧配置策略[J]. 电信科学, 2016, 32(7): 61-67.

Wei JIANG,Shixiao LIU,Heng HU,Chenlu ZHANG. LAA system dynamic sub-frame configuration strategy in unlicensed bands[J]. Telecommunications Science, 2016, 32(7): 61-67.

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参考文献 13

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上下行配置格式	上下行转换周期/ms					子帧号
上下行配置格式	上下行转换周期/ms	0	1	2	3	4	5	6	7	8	9
0	5	D	S	U	U	U	D	S	U	U	U
1	5	D	S	U	U	D	D	S	U	U	D
2	5	D	S	U	D	D	D	S	U	D	D
3	10	D	S	U	U	U	D	D	D	D	D
4	10	D	S	U	U	D	D	D	D	D	D
5	10	D	S	U	D	D	D	D	D	D	D
6	5	D	S	U	U	U	D	S	U	U	D

参数	假设
小区拓扑结构	7小区，正六边形部署，3扇区/小区， 1个簇（2个运营商）/扇区，4个 LAA基站/运营商/簇
系统带宽	20 MHz，单载波
载波频率	5 GHz
微基站发射功率	18 dBm
UE发射功率	18 dBm
簇内微基站的半径	50 m
每个簇内UE的距离	同运营商之间大于3 m，异运营商间大于10 m
UE噪声参数	9 dB
路径损耗	微基站—微基站，微基站—用户：TR 36.814^[12]ITU Umi；
	用户—用户：TR 36.843（D2D）
穿透损耗	室外：0 dB
	室内：27 dB+0.5 din（din是[0,min（25，用户到微基站的距离）的一个随机数值]）
阴影衰落	ITU Umi（参照TR 36.814表B.1.2.1-1）
天线配置	下行：2Tx 2Rx 上行：1Tx 2Rx
天线高度	10 m
UE天线高度	1.5m
天线增益+连接器损耗	5 dBi
UE天线增益	0 dBi
传输机制	下行：TM4,QPSK/16QAM/64QAM
	上行：TM1
调度模型	PF
CCA-ED	-62 dBm
业务模型	FTP3，分组大小为0.5 MB