• Journal of information and communication convergence engineering
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• v.7 no.2
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• pp.87-91
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• 2009

Over the past several years both licensed and unlicensed services and devices have enjoyed extensive growth in the wireless marketplace. In some urban areas in the Kazakhstan, the penetration rate of licensed cellular and PCS services is more than 60%. Similarly, the use of unlicensed wireless local area network technologies has grown significantly as these systems have been deployed in homes, offices, and 'hot spots' in restaurants, hotels, public meeting areas, etc. As more services are wirelessly enabled and as technologies continue to evolve, the demand for new spectrum for commercial services will also continue to increase. Thus, the appropriate regulatory models for future spectrum allocations will continue to be debated throughout the wireless industry.

• ETRI Journal
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• v.44 no.4
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• pp.531-542
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• 2022

With the increasing demand for unlicensed spectrum, several regulators have been opening up the 6-GHz band for unlicensed use while ensuring compliance with the technical requirement to avoid harmful interference in the existing primary services (PSs). In this paper, we present two methodologies, a channel-based method and a frequency-based method, which are applicable to a frequency coordination system that calculates the permissible transmit power in the channels or frequencies available to a secondary service (SS). In addition, we have demonstrated that the available transmit power of an SS can be maximized by adjusting the power allocation of the assigned resource units under the condition that the channel of the SS is partially overlapped with that of the PS. Based on the analysis results, it is suggested that it would be better to utilize the two methods selectively according to the operating channel conditions of the PS and the SS.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.49 no.8
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• pp.70-76
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• 2012

In this paper, we propose a power allocation scheme of the unlicensed user based on orthogonal frequency division multiplexing (OFDM) in the TV white space (TVWS). Power constraints in TVWS should be satisfied in the time domain. However, because OFDM has high PAPR (peak-to-average power ratio), it is difficult to satisfy power constraints of TVWS in the time domain. Furthermore, the conventional power allocation schemes cannot be generally applied to unlicensed user in TVWS. Therefore, we propose a power allocation scheme to satisfy power constraints of TVWS by reducing PAPR in the time domain. In addition, we analyze the capacity of the unlicensed user based on OFDM in a closed form. Based on the capacity analysis, as the number of subcarriers decreases, the capacity can be enhanced. In simulation results, we show that the capacity of the unlicensed user increases, as the number of subcarriers decreases and the mean of the channel between the transmitter and the receiver of the unlicensed user increases.

• The Journal of the Korea Contents Association
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• v.10 no.2
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• pp.320-329
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• 2010

As software producers have tried to keep their profit against illegal piracy, contents producers also want to protect their contents from unlawful sharing among users. Some researchers uncovered that the regulation on the unlicensed contents is not the best policy to maximize their profit mainly due to network effect but this issue has been still controversial. In this paper, we develop a model to investigate the effect of regulation against unlicensed contents sharing on the profit of contents producers and present the optimal condition to maximize profit of contents producers under the regulation and non-regulation of unlicensed contents. As a result, we analyzed that the firm's payoff under the regulation on unlicensed contents is not always greater than the payoff under the non-regulation because of network externality. If the additional utility from off-line purchase of type P consumers (who enjoy the additional benefit of off-line purchase) is large enough, then the firm's payoff is maximized without regulation.

• Journal of Society of Preventive Korean Medicine
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• v.23 no.1
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• pp.15-26
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• 2019

Background and Aim : Health care and cosmetics as well as quality of life is now a matter of concern and many categories of complementary and alternative medicine fall into the territory of the medical practice of Korean medicine. Accordingly, penalties are being taken for unlicensed medical practices of Korean medicine in so called complementary and alternative medicine area. There is a possibility of violating the law for the public part because it is not clearly stipulated in the law as to what is a licensed medical practice. Materials and Method : The significance of the Medical Service Act and the Act on Special Measures for the Control of Public Health Crimes were reviewed, and the related supreme court cases were discussed upon the legal aspect of processing the unlicensed medical practice of Korean medicine. The legal information was provided from the National Law Information Center of the Ministry of Government Legislation, and the information websites of the Supreme Court and the Constitutional Court. Results : The concept of medical practice, which is essential in judging the case of unlicensed medical practice, is 'prevention and treatment of diseases through diagnosis, examination, prescribing, medication, or surgical procedures based on medical expertise', and the 'acts that may result in harm and injury of health unless performed by a medical person'. With respect to the medical practice of Korean medicine, the concept includes 'prevention and treatment of diseases using the principle of traditional Korean Medicine'. Conclusions : The concept of medical practice should be clearly stipulated in the law for the control over the unlicensed medical practices of Korean medicine. And it is important to move from the current concept of medical person-oriented medical practice emerging from the national system of healthcare control, to a concept that can accept the era of health managing-oriented medical environment and the co-governance of the healthcare providers and consumers for the future.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.44 no.10
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• pp.169-177
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• 2007

Existing wireless access (mobile) routers are based commonly on the network address and port translation (NAPT) technique which permits simultaneously sharing a subscriber's connection to the network with multiple users. However, the NAPT architecturally makes the users invisible on the network side, thus becoming a user-oriented connection technique. In this paper, we propose a novel service provider-oriented unlicensed nomadic access relay station (WiNNERS) for helping wireless broadband network service providers to make their business more lucrative by accommdating unlicensed band users as subscribers into their network. The WiNNERS offers service providers the capability to directly manage each of the unlicensed band users at the network side. This direct management allows the service providers to flexibly and simply handle QoS, access control, and billing for each user. In order to distinguish each of the unlicensed band users the WiNNERS constructs a virtual tunnel from each user's terminal to the network access router using connection identifiers which is defined for service flow management within the WiBro system, Consequently, our proposed service provider-oriented relay station can be included into the WiBro network system with minimum modifications.

• The Korean Society of Law and Medicine
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• v.23 no.3
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• pp.117-137
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• 2022

Today, the medical system is changing into a comprehensive health care system in which collaborative relationships between medical professionals and non-medical personnels in neighboring occupational areas. The current medical act brands such "collaboration" as unlicensed medical practice, and punishes non-medical personnel who acted in the risk management of doctors as well as doctors collaborated with non-medical personnel as unlicensed medical practice. In order to narrow the gap between the legal system that regulates unlicensed medical practices and the medical reality, it is necessary to overcome the structural limitations of dualistic, nationalistic, and identity-oriented regulation of unlicensed medical practices. The legal interests of unlicensed medical practice have a dual nature as a personal legal interest of "human life and body" as well as a national legal interest of "maintenance and protection of the nation's medical license system", and it should be noted that the criteria for judging the legal interests protected by the regulations of criminal punishment should be found in "personal legal interest theory." In addition, when determining which behavior is a medical practice and evaluating its risk, the dimension of behavior and measures should be considered in a fair manner without being biased against the subject (identity) of the action. In other words, judging unlicensed medical practice should depend on whether the risk of side effects that may result from the act is reasonably managed. Considering the prospect of therapeutic dialogue between medical professionals and patients, it would be desirable for medical law policies to move in a way that does not fundamentally block the possibility of collaboration among pluralistic medical personalities.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.11
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• pp.2015-2021
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• 2017

Recently, a lot of attention is fallen to IoT(Internet of Things) for hyper-connected society and the number of unlicensed wireless device has been increasing. Thus, this paper analyzed the impact of unlicensed wireless device on the basis of 802.11ah on licensed LTE user equipment in 900 MHz frequency band for efficient frequency use. As the interference analysis method, Minimum Coupling Loss (MCL) method and Monte Carlo (MC) method were used. In case of one interferer, minimum separation distance between interferer and victim was calculated as about 22 m through the MCL method under the assumption of the worst case. The maximum number of interferer to meet the interference probability of 5% below within a cell radius of the victim was computed as about 3000 by using MC method based on statistical technique. The analysis method and results in this paper are expected to be used for the coexistence between unlicensed wireless device and licensed wireless device.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.7B
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• pp.632-641
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• 2006

Recently FCC has considered about the unlicensed device operation in licensed bands. However, this operation can give the harmful interference to the existent licensed system while unlicensed devices operate. Therefore, there should be strict requirements to protect licensed system. So in this paper we propose dynamic frequency selection method in the MAC layer, which is based on the cognitive radio technology. The proposed dynamic frequency selection method creates channel lists after sensing the licensed channels. And it helps the CR base station immediately to moves the current channels that are used by the unlicensed system to other available bands dynamically when a licensed system's signal is detected. This method can reduce interference that is caused by unlicensed devices. In addition, it can maximize channel utilization with enabling coexistence of unlicensed system and licensed system.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.26 no.4
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• pp.374-380
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• 2015

With explosion of wireless traffic it is required to further investigate the technologies on acquiring available spectrum resources and on sharing frequency with existing users. In 3GPP, it is started to study on feasibility and functional requirement of LTE standard in order to extend cellular services offered on only licensed band to 5 GHz unlicensed band. Operating scenario on LTE in unlicensed band is focused on carrier aggregation with licensed band, and the coexistence with Wi-Fi services in 5 GHz band is concerned as a major requirement. For a single global solution framework for licensed assisted access to unlicensed spectrum, listen-before-talk(LBT) mechanism of European regulation for fair access to channel under the coexistence environments is currently examined in 3GPP. In this paper, we evaluate two types of LBT, frame based equipment and load based equipment, with considering LTE carrier aggregation feature and performances of file transferred time and throughput.