Research Presentations

• Channel Coding Scheme for Advanced Digital Satellite Broadcasting System
  Akinori HASHIMOTO, Yoichi SUZUKI, Masaaki KOJIMA, Takeshi KIMURA, Shoji TANAKA and Kazuyoshi SHOGEN↓summary

  summary

  Increasing the symbol rate by using a low roll-off factor of 0.1 and decreasing the required C/N by using LDPC codes enables the channel coding scheme for the advanced digital satellite broadcasting system to achieve an information bit rate of 70 Mbps, a more than 30% increase compared to the current system, without enlarging the occupied bandwidth. This paper describes the technologies composing the channel coding scheme, such as the frame structure and the modulated signal format, as well as its transmission performance. Evaluation tests conducted by ARIB are also reported.

• Forward Error Correction Techniques for the Advanced Satellite Broadcasting System
  Yoichi SUZUKI, Akinori HASHIMOTO, Masaaki KOJIMA, Shoji TANAKA, Takeshi KIMURA and Kazuyoshi SHOGEN↓summary

  summary

  This paper describes the design of LDPC codes whose code lengths are suitable for the transmission frame format of the Advanced Satellite Broadcasting System. First, we describe the requirements of the forward error correction scheme of the new system and the system's coding parameters. Second, we describe a method for eliminating cycles 4 and 6 in the parity check matrix and the parameters of the matrices. Third, we describe a computer simulation using an AWGN channel model. Finally, we discuss the optimization result of a computer simulation of the radius ratios of LDPC-coded 16APSK and 32APSK modulations.

• Efficient Multiplexing Scheme for IP packets over the Advanced Satellite Broadcasting System
  Shuichi AOKI and Katsunori AOKI↓summary

  summary

  Implementing an IP-based transport mechanism in broadcasting systems is useful for multimedia broadcasting applications in the era of broadcast-telecommunication fusion. The overhead of multiplexing methods for IP packet transmission over MPEG-2 systems is quite large, and they are not well suited for efficient transmission of IP packets. We developed an efficient scheme for transporting IP packets over broadcasting channels. The scheme includes a header compression technique for IP packets, transmission control signals for listing IP multicast group addresses, and a simple encapsulation technique suitable for the broadcasting channel. The scheme is adopted as a multiplexing scheme for file-based content delivery on the advanced satellite broadcasting system in Japan. This paper describes the multiplexing scheme and its theoretical overhead. Our experiment on a prototype transmission system shows that the multiplexing scheme can efficiently transport IP packets with a small overhead.