• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.1A
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• pp.24-33
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• 2007

In this paper, two different dynamic cell coordination strategies for frequency flat and selective fading are proposed for efficient subcarrier allocation in the joint consideration of adaptive modulation and variable frequency reuse in the channel-aware OFDMA downlink multicellular environment. Compared to a conventional OFDMA system without cell coordination, where system throughput may become degraded due to the persistent interference from other cells, the proposed system dynamically allows RNC to apply different reuse factors on each subchannel and scheduling in consideration of channel and interference conditions of individual users so as to increase the system throughput and guarantee QoS of each user. In a frequency flat fading, the dynamic scheme with the proposed scheduling achieves on average three times larger throughput than the conventional dynamic scheme [8]. In a selective fading channel, the proposed schemes showed 2.6 times as large throughput as that of a single reuse factor of one for all subchannels.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.3
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• pp.379-388
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• 2020

The contents and scope of this study are to analyze the problems of the current radio service and radio station classification system, and to investigate the radio wave management cases in the United States to provide a reasonable and efficient radio wave management method. The results of this study can be used as basic data when revising the legal system regarding radio wave enforcement regulations, radio service and radio station classification standards. It is expected that in the future, a detailed commentary on the definition and classification system of new radio / radio stations will be prepared to increase policy compliance in practice, while contributing to enhancing the consistency and efficiency of radio station licensing and inspection.