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Lee S.-J.,Korea Radio Promotion Agency Korpa | Kang W.,Yonsei University | Seo J.,Yonsei University
IEICE Electronics Express | Year: 2010

In this letter, a new pulse shaped OFDM-Superposed Quadrature Quadrature Amplitude Modulation (OFDM-SQ2 AM) sys-tem is proposed to reduce the inter-channel interference (ICI) as well as to maintain the orthogonalities between the OFDM subcarriers in the presence of the subcarrier frequency offset. Time and frequency dispersion properties of the proposed SQ2 AM pulse shape are analyzed using the Heisenberg parameter and in-band energy function. Such properties of the proposed pulse are compared with those of a rectan-gular pulse and IOTA pulse. The BER performance of the pulse shaped OFDM-SQ2 AM is compared with those of conventional OFDM-QAM and IOTA/OFDM-OQAM in the 3GPP ITU-R environment. Our simulation results indicate that the proposed OFDM-SQ2 AM achieves higher spectral efficiency and power efficiency as compared to the other schemes and gives better robustness of the frequency dispersion. © IEICE 2010.

Kang W.,Yonsei University | Lee S.-J.,Korea Radio Promotion Agency Korpa | Seo J.,Yonsei University
IEICE Electronics Express | Year: 2010

A new transmission protocol using MIMO (Multiple Input Multiple Output) half-duplex relays is proposed to improve the capacity and the diversity gain of uplink relay communication systems. The proposed protocol employs two half-duplex DF (Decode-and-Forward) relays and Alamouti coded 2 × 2 MIMO communication for links between each relay and the destination. A low complexity receiver using maximum ratio combining and Alamouti decoding is introduced to detect the signal of the proposed protocol. Performance is evaluated by theoretical analysis and computer simulations, and the results show that the proposed protocol outperforms conventional IEEE 802.16j systems in terms of ergodic capacity and outage probability. © IEICE 2010.

Hur N.,Electronics and Telecommunications Research Institute | Lee H.,Electronics and Telecommunications Research Institute | Lee G.S.,Electronics and Telecommunications Research Institute | Lee S.J.,Korea Radio Promotion Agency Korpa | And 2 more authors.
IEEE Transactions on Broadcasting | Year: 2011

In this paper, the authors present three-dimensional television (3DTV) broadcasting and distribution systems that are employed to deliver a pair of stereoscopic images to mobile users, as well as users at home. First, mobile 3DTV systems and services based on DMB and DVB-H are respectively introduced. Second, fixed and high-definition 3DTV systems and services based on terrestrial digital broadcasting are described along with an introduction of experimental 3DTV services in Korea. To be specific, the authors summarize 3DTV systems from the viewpoints of target services, system and user requirements, system configurations, broadcasting trials, related standards, and technical challenges. © 2011 IEEE.

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