Journal of Computer Applications ›› 2019, Vol. 39 ›› Issue (9): 2652-2657.DOI: 10.11772/j.issn.1001-9081.2019020262

• Network and communications • Previous Articles     Next Articles

Low complexity narrowband physical downlink control channel blind detection algorithm based on correlation detection

WANG Dan, LI Anyi, YANG Yanjuan   

  1. School of Communication and Information Engineering, Chongqing University of Posts and Telecommunications, Chongqing 400065, China
  • Received:2019-02-18 Revised:2019-05-21 Online:2019-09-10 Published:2019-06-03
  • Supported by:

    This work is partially supported by the National Natural Science Foundation of China (61701063), the National Science and Technology Major Project (2017ZX03001021-004).


王丹, 李安艺, 杨艳娟   

  1. 重庆邮电大学 通信与信息工程学院, 重庆 400065
  • 通讯作者: 李安艺
  • 作者简介:王丹(1981-),女,重庆人,高级工程师,博士,主要研究方向:无线通信系统;李安艺(1994-),女,河南平顶山人,硕士研究生,主要研究方向:物理层移动通信协议;杨艳娟(1992-),女,山西晋中人,硕士研究生,主要研究方向:物理层移动通信协议。
  • 基金资助:



In NarrowBand Internet of Things (NB-IoT) systems, the Internet of Things (IoT) terminals should decode Downlink Control Information (DCI) quickly to receive resource allocation and scheduling information of the data channel correctly. Therefore, a low complexity Narrowband Physical Downlink Control Channel (NPDCCH) blind detection algorithm using correlation detection was proposed for NPDCCH with search space size being greater than or equal to 32. By employing two correlation judgments on the data in a possible minimum repetition transmission unit of NPDCCH, the invalid data in searching space was removed to reduce the computation complexity. Then, the repetition periods with the valid data were combined and decoded to improve the blind detection performance. Finally, theoretical and simulation analysis of two correlation thresholds used in correlation detection were carried out. Results show that compared with conventional exhaustive blind detection algorithm, the decoding complexity of the proposed algorithm is reduced by at least 75% and the detection performance gain is increased by 2.5 dB to 3.5 dB. The proposed algorithm is more beneficial for engineering practice.

Key words: Narrowband Internet of Things (NB-IoT), Narrowband Physical Downlink Control Channel (NPDCCH), blind decoding, correlation detection, combining algorithm


在窄带物联网系统(NB-IoT)中,物联网(IoT)终端应当快速获取下行控制信息(DCI),以便正确接收数据信道的资源分配和调度信息。为此,针对窄带物理下行控制信道(NPDCCH)搜索空间大小大于等于32时,提出一种利用相关检测的低复杂度的NPDCCH盲检测算法。首先,通过对一个NPDCCH可能最小重复传输单元进行两次相关判决,剔除搜索空间中其他无效的数据,以降低计算复杂度;然后,对判决为有效数据所在的重复周期进行合并译码,以提高盲检性能;最后,对两个相关阈值设定进行了理论与仿真分析。仿真结果表明,相比穷举盲检测算法,所提算法在计算复杂度上至少降低了75%,检测性能提高了增益2.5~3.5 dB,更加利于工程实践。

关键词: 窄带物联网, 窄带物理下行控制信道, 盲检测, 相关检测, 合并算法

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