# Preamble Design and Collision Resolution in a Massive Access IoT System
## 3 Preamble Design
### Sub-Preamble Sequence Design
**Funding:** This research was funded by the National Natural Science Foundation of China under Grant 61871062; in part by the Natural Science Foundation of Chongqing under grant cstc2020 jcyzdxmx0024; in part by the Science and Technology Research Program of Chongqing Municipal Education Commission under grant KJQN201900609; in part by the Program for Innovation Team Building at Institutions of Higher Education in Chongqing under Grant CXTDX201601020, and in part by the University Innovation Research Group of Chongqing under grant CXQT20017. **Institutional Review Board Statement:** Not applicable. **Informed Consent Statement:** Not applicable. **Data Availability Statement:** The data presented in this study are available on request from the corresponding author. The data are not publicly available due to further study will be carried out. **Conflicts of Interest:** The authors declare no conflict of interest. Figure 9: TA capturing accuracy. ## References

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