A5031839568- Advanced MIMO Systems Optimization
- Advanced Wireless Communication Techniques
- Telecommunications and Broadcasting Technologies
- Wireless Communication Networks Research
- Advanced Wireless Communication Technologies
- Radar Systems and Signal Processing
- Cognitive Radio Networks and Spectrum Sensing
- Wireless Signal Modulation Classification
- IoT Networks and Protocols
- Energy Harvesting in Wireless Networks
- Cooperative Communication and Network Coding
- Vehicular Ad Hoc Networks (VANETs)
- Human Mobility and Location-Based Analysis
- Stock Market Forecasting Methods
- Wireless Communication Security Techniques
- Antenna Design and Analysis
- Antenna Design and Optimization
- Software-Defined Networks and 5G
- Millimeter-Wave Propagation and Modeling
- Complex Network Analysis Techniques
- Advanced Computing and Algorithms
- Digital Marketing and Social Media
- Bluetooth and Wireless Communication Technologies
- PAPR reduction in OFDM
- Power Line Communications and Noise
Sookmyung Women's University
2018-2025
Yonsei University
2023
Kyonggi University
2023
Odem softwarization, where baseband signals are fully processed using software on a general-purpose CPU, is promising technology in mobile communications due to its simplicity and flexibility realizing various features. On the other hand, many still question effectiveness of softwarized modem commercial environments concerning performance complexity. Motivated by this perspective, paper presents design implementation with specific feature 5G cell search for field evaluation. Based baseline...
In order to maintain stable communication in 5G wireless networks, the link between a base station and user equipment (UE) should be constantly monitored adapted time-varying channel. The use of UE for seamless information exchange is based on obtaining target reference signal. method used obtain signal involves identifying index received from stations. However, existing identification employed commercial networks blind detection method, which inefficient terms time can cause misdetections....
This paper demonstrates the implementation of a space–frequency line coded-orthogonal frequency-division multiplexing (SFLC-OFDM) system. The SFLC-OFDM system utilizes downlink channel state information at transmitter, which can be obtained from uplink estimation under reciprocity assumption between uplink-and-downlink channels. However, in practical implementations, is violated due to imperfect synchronization and radio frequency chain mismatch transceivers. To recover reciprocity,...
To support the vehicular communication services that require low end-to-end transfer latency, long-term evolution (LTE) specification recently defined a new channel <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">sidelink</i> , which enables direct data among vehicle user equipments (UEs) without aid of network infrastructure. Since sidelink transmitter is not able to have receiver information due lack feedback channels, UE unconditionally...
This paper presents field experiment results that illustrate the impact of cross-link interference on cell search procedure in a 5G time division duplex system. We initially show how affects to from an analytic aspect. An example experimental result provided this shows user equipment wrongly estimates symbol timing offset due interference. Furthermore, we propose modified algorithm which is robust against strong influence The proposed modification efficiently suppresses effects by applying...
LoRa Wide Area Networks (LoRaWAN) can provide a connectivity service to Internet of Things (IoT) for an extremely long run-time and with low power consumption. As the LoRaWAN is extensively applied various IoT scenarios, solutions face flexibility issue in terms inter-operating kinds modem hardware protocol scenarios. In this regard, we design unified architecture physical layer, which flexibly correspond deployment operational cases. The new includes abstraction sub-layer, contains...
Unlike the Long Term Evolution (LTE), 5G system faces an additional issue of detecting appropriate beams in a cell search phase. This paper investigates effect residual Symbol Timing Offset (rSTO) on beam index detection and proposes practical scheme that compensates for rSTO SoftWare (SW) Modem environment. For evaluating performance at implementation level, we realize proposed real-time testbed conduct experiments with commercial base stations. The experimental results prove practically...
5G adopts Discontinuous Reception (DRX) technology, which enables the User Equipment (UE) to repeat sleep and wake-up cycles for power-saving. To minimize power consumption, UE needs re-synchronize a downlink signal transmitted from serving gNodeB (gNB) each DRX occasion. have synchronization technique suitable occasions, we design implement history-based scheme that can effectively manage window of detection. The proposed primarily considers statistics previously detected timing offsets...
Carrier Frequency Offset (CFO) is critical to the decoder performance of an Orthogonal Division Multiple Access (OFDMA) system and conventional research works have coped with this issue. On other hand, excessive enhancement estimation accuracy causes redundant computational complexity, which not desirable for SoftWare (SW) defined modems that solely conduct signal processing in a software environment. In paper, we propose design methodology two-step CFO estimator controls specific level...
Near-optimal transmit beamformers are designed for multiuser multiple-input single-output interference channels with slowly time-varying block fading. The main contribution of this article is to provide a method deriving closed-form solutions effective beamforming in both low and high signal-to-noise ratio regimes. proposed basically leverages side information obtained from the channel correlation between adjacent coding blocks. More specifically, our methodology based on linear algebraic...
This paper addresses an uplink (UL) scheduling issue that arises in the midst of recent trend applying commercial long term evolution (LTE) technology to public safety. Mission critical push-to-talk (MCPTT), which specifies a group communication service over LTE public-safety scenarios, needs satisfy requirements extremely short latency for its control procedures. We herein propose practical UL-scheduling scheme, can be feasible system shorten time initial UL transmissions. Through empirical...