The authors are conducting research on a next generation mobile Field Pick-up Unit (FPU) system that enables wirelessly relaying ultra-high-definition video materials such as road race broadcasting programs. We are working on increasing the capacity by 4×4 TDD-SVD-MIMO technology that adaptively controls transmit parameters depending on channel conditions. We are also researching on frequency sensing technology and variable rate video coding technology toward realization of mobile relay of 4K/8K program materials. In this paper, we report on the outline of the proposed system and the technologies which build up the system.
In order to expand a capacity of mobile relay FPUs, the authors have been researching a 4x4 TDD-SVD-MIMO system with adaptive transmission control which changes beam-forming weights and modulation schemes in accordance with channel conditions. We prototyped a proposed system and evaluated its transmission performance by indoor experiment using a fading simulator. The result showed that our prototype system achieved a BER performance with degradation less than about 2 dB from that of computer simulations and demonstrated the proposed technique in actual hardware.
The authors examine increasing the capacity toward 4K/8K transmission of mobile FPU (Field Pick-up Unit) system used for marathon broadcast, etc. A rate matching scheme that uses bit-puncturing and controls coding rate enables higher radio transmission video rate without bit error occurring in mobile propagations. This report describes the Turbo code's puncturing method for rate matching, the implementation method of rate matching in combination with our 4x4 TDD-SVD-MIMO system and some computer simulation results. In conclusion, it shows that the proposed rate matching can obtain a higher transmission rate than the transmission with conventional fixed coding rate codes.
We are conducting research on the next-generation 1.2-GHz/2.3-GHz-band mobile field pick-up unit(FPU) system that can wirelessly transmit Super Hi-Vision video materials. We have so far proposed the 4×4 TDD-SVD-MIMO system that adaptively controls transmit parameters depending on channel conditions, and evaluated the transmission performance by both computer simulation and indoor measurements that used our prototype system. In this report, we describe an outdoor experiment to test the prototype system in the urban area around NHK technical laboratories. Our results showed that the prototype system could achieve the transmission rate of more than 100 Mbps in mobile environments.
We are conducting research and development on the 2.3-GHz-band mobile relay FPU that can wirelessly transmit Super Hi-Vision video materials. We need radio propagation models based on actual mobile propagation environments to evaluate the transmission performance of our prototype FPU. We conducted propagation experiments using a 2.3-GHz-band experimental radio station, and proposed a method to make radio propagation models from power delay profiles obtained by analyzing channel responses of the received pilot signals. In this report, we describe the proposed method of modeling.
We are conducting research and development on the 2.3-GHz-band mobile relay FPU that can wirelessly transmit Super Hi-Vision video materials. We need radio propagation models based on actual mobile propagation environments to evaluate the transmission performance of our prototype FPU. We conducted propagation experiments using a 2.3-GHz-band experimental radio station, and proposed a method to make radio propagation models from power delay profiles obtained by analyzing channel responses of the received pilot signals. In this report, we describe some radio propagation models of both urban and suburban areas that we made based on the proposed method.
Time Division Duplex (TDD)-based bidirectional digital field pick-up unit (FPU) system is now studying. Hence this digital FPU system shares its frequency band with other wireless systems, digital FPU system should detect and avoid the interference from other systems which signal format is unknown. We studied the spectrum sensing scheme using the received power within preamble signals of FPU system. From the results of the baseband link-level computer simulation, it was confirmed that the proposed scheme achieved an excellent performance of the interference detection.
The next generation Field Pick-up Unit (FPU) system is now being developed. In order to achieve high throughput transmission, it is important to improve the quality of transmission and also to improve the spectral efficiency. Hence the mobile transmission FPU system uses shared frequency bands in 1.2GHz and 2.3GHz with other radio systems, we are studying about interference detection and avoidance method for the FPU system. In this paper we studied the frequency switching method for interference avoidance and perform an outdoor experiment. From the result of the outdoor field trial, it was confirmed that the proposed method exhibits good performance.
In the road race, the image picked up by the 8K camera is high compressed by the 8K encoder and transmitted to the receiving base station by the FPU. Also, at the receiving base station, the FPU received signal is decoded by the 8K decoder. This presentation shows a technical examination for realization of 8K encoder and decoder.