• Journal of Advanced Navigation Technology
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• v.17 no.6
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• pp.633-637
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• 2013

By using geolocation and maps, we need to trace the path of ourselves, others, or the objects. Until now, we used a native apps development mehod to develop path tracking systems in mobile devices such as smart phones and tablet computers. A disadvantage of this method is that we have to work again to provide the same service on different platforms. Web Apps and Hybrid Apps are developed to recover this disadvantage. Since Hybrid Apps look like Native Apps apparently, users prefer Hybrid Apps to Web Apps. In this paper, we develop a hybrid app which can trace the path on mobile devices. The recently suggested next generation markup language, HTML5, has geolocation features. By using them, we implemented a hybrid app for a path tracking system. First, we create a web app using HTML5, CSS, and JavaScript, Then, PhoneGap, a mobile development framework, is used to convert it to the hybrid app. By implementing hybrid app, various apps which need path tracking can be developed rapidly and effectively, regardless of the mobile devices.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.4B
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• pp.275-280
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• 2002

Wireless communications have been developed time and time to satisfy more demands of users for internet service, mobile communication service and so on. One of infrastructures leading the next generation wireless communication is HAPS(High Altitude Platform Station). This paper analyzed outage probability when a mobile communication system was constructed by using HAPS. First, an approach to evaluate the carrier to interference power ratio' was introduced and results from the analysis were calculated and simulated. from the results, carrier to interference power ratio (C/I) and fading depth (K) had an effect on outage probability; outage probability decreases when K increases far constant C/I or C/l increases for constant K. In addition, when outage probability for a platform with elevation 30 degrees is expanded into it for 24-platforms, outage probability(C/I=9.8dB) was worse because of many interferers relatively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.2
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• pp.364-369
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• 2009

Today, as various access technologies appear, for example WiMax, WiBro, the demand for spectrum is increasing rapidly. Spectrums are a national resource with scarcity value so that we need to a]locate them effectively for the national economy and industry. Accordingly, In the paper, we proposed several factors and new model for estimating spectrum requirements of a next generation mobile network with multimedia data services. These are self-similarity characteristics of data traffic, engineered capacity considering QoS, structure of FA increase, asymmetry of data traffic between uplink and downlink, handoff traffic, and uneven traffic pattern among base stations. It can applied mobile WiMax or other wireless broadband systems in general.

• Convergence Security Journal
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• v.20 no.3
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• pp.47-52
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• 2020

The introduction of virtualization technology in the broadcasting field is actively progressing broadcasting service automation and intelligence based on the effective operation of IT resources throughout the broadcasting industry ecosystem. In recent years, there is increasing interest in increasing the flexibility of various broadcasting resources and increasing the efficiency of interworking with other networks through network virtualization of the broadcasting network infrastructure. The fundamental transformation from the broadcasting network to the IP paradigm is facing a situation where it is necessary to solve various problems for the effective interworking of Internet-based service platforms and 5G networks and the development of new convergence services. In other words, for organic and effective interworking with the next-generation broadcasting network represented by ATSC 3.0, a mobile communication network represented by 5G, and the Internet, a number of difficulties must be solved. In this paper, the basic technology and status for the convergence of ATSC 3.0 broadcasting network and mobile communication network represented by 5G was examined, and a plan for the ATSC 3.0 broadcasting network and 5G network to interwork with each other as a network was described.

• Journal of Digital Convergence
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• v.12 no.5
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• pp.115-123
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• 2014

Patent information analysis has been carried out for technological capability analysis of competitors relating to next generation mobile communication. Various analysis methods, such as applicant analysis, technology classification analysis, indicator analysis and the like have been utilized as a method of analyzing patent information. As a first step for the technological capability analysis of competitors, applicants having high patent activity(PA) were selected, and as a second step therefor, technology classifications showing high technological independence (TI) were selected. Furthermore, portfolios for technology classifications showing high technological independence in the patents of main applicants having high patent activity by matching results the first and second steps together were prepared. Through such a process, portfolios for important technologies which have been concentrically researched by competitors could be analyzed. Accordingly, the present analysis results will help to carry out strategic R&D management, such as the establishment of company R&D plans and patent strategies.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.44 no.1
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• pp.1-9
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• 2007

Digital Multimedia Broadcasting is the next generation broadcasting service which enables various digital multimedia contents, i.e., audio and video, and data access for mobile users. However, due to the bandwidth limitation, the spatial resolution is limited to CIF(Common Interleaved Frame). The Advanced Terrestrial DMB (AT-DMB) secures additional bandwidth by adopting hierarchical modulation transmission technology and provides high data rate and quality for mobile multimedia broadcasting services with scalable video coding(SVC). This paper proposes scalable video coding technology for AT-DMB which enables high quality mobile multimedia broadcasting services that exceeds current DMB service's quality and contents capability.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.10
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• pp.2473-2481
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• 2014

The majority of next generation information systems will be working on portable mobile devices such as smartphones. REST Open API web services have quickly become popular among mobile application development. The use of REST web services are not only growing in popularity but totally changing the way of mobile applications development. This is because REST web services could be used in application development as a form of building blocks, which is completely independent, compatible, to any platforms. With this strength, REST web services encourage third party application to build add-on functionality. This research proposes the use of REST web service to replace the use of socket APIs into major internet communication APIs. To this end, this paper also provide performance evaluation of the REST web services compared to the conventional socket APIs, focusing on scalability by analytical and experimental evaluations. Finally, we summarize the possibility whether REST Open API web services have enough performance as future major internet communication primitive APIs.

• Journal of Advanced Navigation Technology
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• v.6 no.1
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• pp.44-51
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• 2002

This paper describes the performance evaluation and analysis of an Orthogonal Frequency-Division Multiplexing (OFDM) system having the least Inter Symbol Interference (ISI) in a multi-path fading channel environment. Wireless Local Area Network (W-LAN) in accordance with IEEE 802.11a and IEEE 802.11b provides high-speed transmission to universities, businesses and other various places. In addition, service providers can offer a public W-LAN service on restricted areas such as a subway. The proliferation of W-LAN has led to greater W-LAN service demands, but problems are also on the rise in offering a good W-LAN service. In particular, urban areas with high radio wave interference and many buildings are vulnerable to deteriorated QoS including disconnected data and errors. For example, when high-speed data is transmitted in such areas, the relatively high frequency generates ISI between Access Points (AP) and Mobile Terminals (such as a notebook computer), leading to a frequency selective fading channel environment. Consequently, it is difficult to expect a goodW-LAN service. The simulation proves that the OFDM system enables W-LAN to implement QoS in high-speed data transmission in a multi-path fading channel environment. The enhanced OFDM performance with 52 sub-carriers is verified via data modulation methods such as BPSK, QPSK and 16QAM based on IEEE 802.11a and punched convolutional codes with code rate of 1/2 and 3/4 and constraint length of 7. Especially, the simulation finds that the OFDM system has better performance and there is no data disconnection even in a mobile environment by applying a single tap equalizer and a decision feedback equalizer to a mobile channel environment with heavy fading influence. Given the above result, the OFDM system is an ideal solution to guarantee QoS of the W-LAN service in a high-speed mobile environment.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.6B
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• pp.601-609
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• 2002

In multi-path wireless channels with time-variant delay profile, a mobile station measures the received signal strength and report it to network which performs network control function such as handover. In order to improve the maximum ratio combining (MRC) gain, it also should search the strongest signal paths and measure their time offsets fast and exactly. This paper proposes some methods of fast and exactly measuring the multi-path signal strength and time offset. Since the W-CDMA system adopts antenna diversity technique for the next generation high speed packet access (HSDPA) service, we derive the optimum design parameter values for the proposed methods through computer simulations under the HSDPA conditions o( low speed of mobile, of no power control, and of multi-path wireless environment with transmit and receive antenna diversity. Finally, we prove the validity of the proposed methods by showing the improvement of the bit error rate (BER) performance.

• The Journal of the Korea institute of electronic communication sciences
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• v.5 no.5
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• pp.516-521
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• 2010

In the high-speed packet service, next generation mobile communication system has emerged as a major feature. If the fire of these high-speed D kit services and non-continuous transmission of data due to the symmetrical nature of daeyiteo traffic for D-CDMA system has been actively studied. In this paper, we apply turbo codes for D-CDMA has been investigated. Considering the nature of the system configuration of the transmission frame type, such as physical channel structure and channel coding has been investigated. In addition to TD-CDMA system, one HARQ gibeopjung hase Combining the performance analysis techniques were applied.