Nankai trough earthquake text information for QZS's disaster and crisis management report test delivery

categories: gnss
tags: dcr qzss

Quasi-Zenith Satellite, QZS or Michibiki, distributes the disaster and crisis management report (DCR) on the L1S radio channel.

A new field, Information Serial Code, has been added to the transmission format of “Nankai Trough Earthquake” in the update of the 10th edition of the interface specification. In addition, DCR test distribution has been done once a month until now, but in March 2022, it will be done twice on the 10th and 28th.

Text information related to the Nankai Trough Earthquake is transmitted 6 UTF-8 Japanese characters per message, and up to 378 characters can be transmitted by concatenating multiple messages. DCR transmits one message every 4 seconds at the shortest, and another DCR message may be inserted in the middle of the multiple messages. In addition, since the text information of the Nankai Trough earthquake is transmitted in no particular order, it is not possible for the receiver to present the information sequentially, and the receiver requires sorting the messages. After all, transmitting textual information of 378 characters needs the receiver at least 4 minutes and 12 seconds to decode the information. In the test distribution so far, the number of characters is very large and it was truncated in the middle of the information text. When a message is missing due to fading at the DCR mobile receiver, it is required to present them with hidden characters or to keep waiting for receiving the missing message.

The text information of the Nankai Trough Earthquake in this DCR test distribution is simple and easy to understand.

(the Japanese text)


(the English translation)

It is estimated that an unusual slow slip occurs at the plate boundary along the Nankai Trough. Due to the occurrence of this unusual slow slip, it is considered that the possibility of large-scale earthquakes is relatively higher in the hypocenter area of the Nankai Trough Earthquake than in normal times. Please take disaster prevention actions in response to further information from the government and the autonomous body.

This text information consists of 158 Japanese characters, so the receiver can present this text in 1 minute and 48 seconds. This isn’t mentioned in the official information, but I think it’s a big improvement. It’s also nice to have a summary with the Information Serial Code.

I am looking forward to the test delivery this month as well.

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