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We have developed a transmission system using ultra-multilevel orthogonal frequency division multiplexing (OFDM) technology, dual-polarized multiple-input multiple-output (MIMO) technology, and Low-Density Parity-Check (LDPC) Codes for experimental purposes on the basis of the conventional digital terrestrial broadcasting transmission scheme, ISDB-T. We conducted two field experiments: one at 23 reception points around NHK Science & Technology Research Laboratories (STRL) using an experimental transmitter installed at NHK STRL, and the other on the lawn at NHK STRL using circularly or skew polarized waves in addition to a conventional polarization set, horizontal and vertical.As a result, we obtained the required field strength in an urban environment when using the 4096QAM carrier modulation scheme with a LDPC code. Furthermore, we confirmed the advantage of circularly or skew polarized waves in an environment in which the received power differed between the horizontally and vertically polarized waves.

ATSC 3.0 is the latest Digital Terrestrial Television (DTT) standard, and it allows a higher spectral efficiency and/or a transmission robustness with Multiple-Input Multiple-Output (MIMO) technology compared to existing DTT standards. Regarding MIMO channel estimation, two pilot encoding algorithms known as Walsh-Hadamard encoding and Null Pilot encoding are possible in ATSC 3.0. The two MIMO pilot algorithms are standardized so as to have the same pilot positions and the same pilot boosting as SISO, and the optimum pilot configuration has not been fully evaluated for MIMO. This paper focuses on the performance evaluation and optimization of the pilot boosting and the pilot patterns for two MIMO pilot encoding algorithms in ATSC 3.0 using physical layer simulations. This paper provides a great benefit to broadcasters to select the MIMO pilot configuration including pilot boosting, pilot pattern and pilot encoding algorithm that better suits their service requirements. Several channel interpolation algorithms have been taken into account as a typical receiver implementation in both fixed SFN reception and mobile reception.

In this study, we investigated six types of mood state (tension-anxiety, depression-dejection, anger-hostility, vigor, fatigue, and confusion) using the Profile of Mood States (POMS) with 40 Japanese university students. We examined five main quality of life (QOL) domains (physical health, psychological health, social relationships, and environmental health) using the World Health Organization Quality of Life Scale (WHOQOL-26). We also examined the total scale score. We examined Spearman's rank correlations between POMS mood state and QOL scores and compared male and female students' scores. The results indicated statistically significant correlations between all six mood states and three broad WHOQOL-26 domains (physical health, psychological health, and social relationships). Moreover, the relationship between mood state and QOL showed a gender difference. There were correlations between mood states and the QOL domains of social relationships and environmental health for males. In contrast, mood state correlated with the QOL domains of physical health and psychological health in females. The findings suggest that genderspecific health provision is needed to care for young university students in Japan. However, our study has several limitations; therefore, larger-scale studies with older subjects are needed in the future.