JungSook Bae

Architecture and performance evaluation of MmWave based 5G mobile communication system

To enhance 1000 times more capacity than the existing mobile communication system, the mmWave band in the 30-300GHz range providing wide bandwidth is being considered as a candidate for new radio bands for 5G mobile communication systems. ETRI is developing mmWave based 5G mobile communication system in the Giga KOREA 5G (GK-5G) project. This paper introduces overview and features of the GK-5G mobile communication system and evaluates performance of the GK-5G mobile communication system through the system level simulation considering real geospatial information.

Next generation mobile service environment and evolution of context aware services

Context aware service which provides best suitable services for a user by analyzing users needs and situational information, will be one of the promising next generation (NG) mobile services. In this paper, we propose the NG mobile service environment based on the NG mobile service platform and evolutional phases of context aware services in the NG mobile service environment. We then introduce the Context Aware Follow-me (CAF) service developed as a prototype of promising NG context aware mobile service followed by introduction of testbed system developed to investigate feasibility of the CAF service

Radio resource management for 5G mobile communication systems with massive antenna structure

In order to accommodate for the emerging mobile data traffic, millimetre-wave mmWave band in 30-300GHz range is being considered for the fifth generation 5G mobile networks. This mmWave band can potentially fulfil the bandwidth requirement of the next generation mobile networks for the next few decades and beyond. In this article, we propose a novel resource allocation scheme for mmWave in 5G mobile networks. The concept of multi-beam coordination is adopted to efficiently utilise the radio resource and improve the network performance in beam boundary regions. Moreover, because the mmWave signal has poor propagation characteristics, a massive antenna structure with beamforming is envisioned in this article. Our system-level simulation results indicate that the proposed scheme improves the resource utilization and network performance, compared with those of Lis and conventional schemes. Copyright

System capacity enhancement of MmWave based 5G mobile communication system

The millimeter wave (mmWave) frequency band is being considered as a candidate for new radio bands that lead to capacity enhancement for emerging 5G mobile communication systems. But, in order to overcome propagation limitations of mmWave band, beamforming technology can be a solution and multi-beam based communication system using fixed beamforming is considered as a communication system structure for 5G mobile. In this paper, we propose inter-beam interference mitigation method for the multi-beam based 5G communication system using fixed beamforming. The proposed method mutes beams that have an effect on inter-beam interference based on proportional fair metric by beam, and improves signal to interference plus noise ratio (SINR) and system capacity.

Provision of User-Centric Mobile Services in Next Generation Mobile Communication Environment

In next generation (NG) mobile communication environment, it is expected that mobile services will be user- centric and the mobile service platform will play an important role in supporting various future mobile services not only for service providers to provide services effectively but also for users to use services easily. In-this-paper,-we propose the architecture, functions and protocols of the NG mobile service platform of the NG mobile service platform which gives efficient means of connecting users and service providers to fulfill user-centric mobile services. Then we describe the NG mobile service environment with focusing on the NG service platform and how user-centric mobile services are provided in the NG mobile service environment. We then introduce the context aware follow-me (CAF) service developed as a prototype of promising NG user-centric mobile service followed by introduction of test- bed system developed to investigate feasibility of the CAF service.

Performance analysis with dynamic beam control using millimeter-wave band on 5G mobile communications

In order to accommodate the ever growing demand of data traffic in future mobile networks, the millimeter-wave frequency band (30--300GHz) is considered as a for beyond 4G networks. However, unlike the conventional sub-3GHz band, the propagation characteristic of millimeter-wave band is poorly propagated toward non-line-of-sight regions. To compensate the loss caused by poor propagation in millimeter-wave band, and utilize the band more efficiently beamforming has considered as a key solution with massive antenna structure (MAS) and spatial division multiple access (SDMA) technologies. In MAS with beamforming, due to the large number of antenna operating very close to each other, yields to a new issue known as inter-beam interference should be significantly researched. In order to solve this issue we propose a dynamic beam control scheme for MAS. Our simulation results shows that the proposed scheme reduces the inter-beam interference and hence increases the overall network capacity.

Gain degradation effect due to beam misalignment on mmWave beamforming for 5G cellular communication

Millimeter wave technology is major candidate technology for 5G network. Because of the high path loss characteristics of the mmWave system, beamforming technique is necessary to overcome this high path loss. Beamforming technology cannot achieve perfect beam alignment and it leads to degradation of the channel gain between the transceiver. Thus, we examine a gain degradation effect due to beam misalignment on mmWave beamforming system. We generated the channel coefficients by using QuaDRiGa channel model implementation. The channel gain analysis results shows that the misalignment of the BS beam causes high channel gain degradation.

Implementation of next generation mobile service: the context-aware follow-me service

With the advent of mobile communication technologies, next generation mobile service is evolving toward user-centric services, in that each user can get a personalized mobile service based on his/her needs. In this paper, we propose the context-aware follow me (CAF) service as a prototype next generation user-centric mobile service. The CAF service is designed to provide optimized service based on various context information such as users location and preference, capability of devices located around a user and characteristics of services in use. We also present an example CAF service scenario, an overall system architecture, a test-bed system and a sample CAF service flows.

Design of a pro-active queue management

In this paper, we introduce and analyze a feedback control model of TCP/AQM dynamics. Then, we propose the pro-active queue management (PAQM) mechanism, which can provide proactive congestion avoidance and control using an adaptive congestion indicator and a control function for wide range of traffic environments. The PAQM stabilizes the queue length around a desired level while giving smooth and low packet loss rates independent of the traffic load level under a wide range of traffic environments. The PAQM outperforms other AQM algorithms such as random early detection (RED) [S. Floyd and V. Jacobson, August 1993] and PI-controller [C. V. Hollot et al., April 2001].

System coverage of Mm wave based 5G mobile communication system

To meet avalanche of traffic volume, the mmWave band in the 30-300GHz range is being considered as a candidate for new radio bands for 5G mobile communication systems. ETRI is developing mmWave based 5G mobile communication system in the Giga KOREA 5G (GK-5G) project. This paper introduces overview and features of the GK-5G mobile communication system and evaluates system coverage of the GK-5G mobile communication system through the system level simulation considering real geospatial information.