arXiv subjects

Chieh-Chun Chen

Publications and source records attributed to Chieh-Chun Chen.

3 recordsLinked to original sources

arXiv2026

Uplink SRS-Based Real-Time Indoor Localization System over OpenAirInterface

Indoor localization is one of the important services for future 5G-Advanced and 6G systems. This paper presents an uplink Sounding Reference Signal (SRS)-based real-time indoor localization system implemented over an OpenAirInterface (OAI) 5G Radio Access Network (RAN). The proposed system uses a Positioning xApp to derive Channel Frequency Response (CFR) measurements from uplink SRS measurements. The SRS measurements are obtained from the gNB through the E2 Service Model for Lower Layer Control (E2SM-LLC) over the standardized E2 interface. The xApp transforms the CFR into a 32-dimensional physics-aware feature vector and uses a Random Forest (RF) regressor to estimate the two-dimensional position of the user equipment. We implemented the Positioning xApp on an OAI-based 5G testbed in a multipath-rich indoor laboratory at EURECOM to validate the proposed system. Experimental results show that the proposed system achieves a mean absolute error (MAE) of 0.12 m under random train-test evaluation. These results demonstrate the feasibility and limitations of uplink SRS-based real-time indoor localization over OAI.

cs.NI↗

arXiv2025

IUP: Integrated and Programmable User Plane for Next-Generation Mobile Networks

Mobile networks evolve on a regular basis to meet the requirements of a rapidly changing application ecosystem; hence, a future-proof design is key to getting the most out of their lifecycle. In comparison to other access networks, one major issue with the 5G Radio Access Network (RAN) is that it behaves as a "fat Layer 2" entity, resulting in disparities in Internet Protocol (IP) flow traffic control and radio resource allocation. In this article, we propose an innovative design - Integrated User Plane (IUP) - that incorporates User Plane Function (UPF) functionalities into RAN, and we introduce the Integrated Data Flow Control (IDFC) sublayer with a new traffic management pipeline and various programmable rules. To understand its implications for crucial mobility user cases, a detailed analysis of how IUP interacts with Control Plane (CP) network functions is conducted. Finally, our IUP prototype shows benefits including a 50% saving in both latency and overhead, converged IUP and non-Third-Generation Partnership Project (3GPP) networks for seamless connectivity, and real-time UP programmability in both traffic control and resource allocation via the O-RAN framework.

cs.NI↗

arXiv2020

Prototyping of Open Source NB-IoT Network

Narrowband Internet-of-Things (NB-IoT) is one of the major access technologies proposed to support massive machine type communications (mMTC) services for the 5th generation (5G) mobile networks. Many emerging services and networking paradigms are expected to be developed on top of NB-IoT networks. This paper summarizes the steps required to build up an open source narrowband Internet-of-Things (NB-IoT) network. This work is a joint research and development (R&D) result from industry and academic collaboration. The open source NB-IoT enhanced Node B (eNB) is jointly developed by B-COM and NTUST based on the well-known OpenAirInterfaceTM (OAI) open source Long-Term Evolution (LTE) eNB developed by EURECOM. The NB-IoT eNB is successfully connected to an evolved packet core (EPC) developed by Nokia Bell Lab. We demonstrate how to use commercial off-the-shelf (COTS) NB-IoT module to forward its sensing data to the Internet via the open source NB-IoT network.

cs.NI↗