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Recently, it has been actively conducted to study Network technology based on eMBB, URLLC, mMTC for 5G commercial. Compared to 4G Network, 5G is leading the sensational dissemination and spread of 5G devices, IoT and network infrastructure with outstanding performance differences such as data transmission speed, communication delay time, and connectivity of devices. However, there is a need for a method to select proper radio access technology(RAT) interworking with the legacy network infrastructure (4G/3G/2G) due to the narrow coverage of 5G. There is a need for a way to improve communication service satisfaction through infrastructure and proper and efficient use. In this paper, we propose a method to support efficient mobility of mobile devices for interworking between 5G mobile networks and existing mobile networks (4G/3G/2G), and scenarios for efficiently operating 5G networks and existing networks of global mobile network operators.

Before GBAS ground systems is installed at the airport, the site survey is needed to determine the suitability of proposed GBAS candidate sites depending on the siting requirements. Therefore, analysis of GPS signal reception environment, one of the site survey steps, is required. In this paper, the number of visible satellites, GPS signal strength, multipath error, radio frequency interference and predicted availability were analyzed using the GPS data of Gimpo International Airport measured by PortaSAT equipments and the analysis results were represented.

This paper presents site survey processes and the results for installing GBAS Category-I ground system into Gimpo international airport. For siting assessment, many things should be taken into account in advance, such as installation requirement of GBAS components, future airport development plan and possible interference effects to existing facilities. Because overall performance of GBAS system can be affected by GPS signal reception environment, on-site survey should be performed carefully to measure actual GPS environmental performance and determine if any adverse multipath or RFI problems exist or not. In addtion, VDB antenna should be located to ensure line of sight for transmitting VHF signal to deliver GBAS message to aircraft. Based on the survey results, final location for GBAS system installation is selected near runway 32 in the Gimpo airport.

Since the site chosen for GBAS ground system will have a direct effect on the performance of the GBAS, the GBAS ground system siting is mightily important in the GBAS installation process. Therefore, in this paper, the major equipment of the GBAS ground system is introduced and a formal process is described for the identification and evaluation of candidate GBAS sites. Also, this paper described detail siting requirements for the GBAS ground system such as reference receiver, VDB antenna and shelter respectively.

We address the MCHO (mobile controlled handover) method between WLAN and CDMA communication. The MCHO method between WLAN and CDMA can be apply to both hard handover and soft handover. We implemented the MCHO method on a wireless mobile terminal between WLAN and CDMA communication. Moreover, the MCHO handover method can be employed in the sequence monitoring and sequence acquisition processes, for example, telematics and remote health care system, etc.

In implementing a portable patient monitoring system and providing mobility to patients who need to measure signals continuously, data transmission over wireless network is very important. In this paper, we consider the transmission of patient monitoring data over wireless networks. We consider the wireless environment in two ways: one is the wireless LAN system for indoor environment, and the other is the public CDMA cellular system for outdoor environment. Also we consider the handover of the data between two environments when the patient is crossing the boundary.