BPC (time signal)
BPC is the callsign of a time signal broadcasting from the BPC Shangqiu Low-Frequency Time-Code Radio Station, cooperatively constructed by the National Time Service Center of the Chinese Academy of Sciences and Xi’an Gaohua Technology Co., Ltd., since April 25, 2002.
BPC transmits a time signal on 68.5 kHz, which can be used for synchronizing radio controlled clocks. As opposed to other time signal transmitters, the signal format is not published openly; a special license is required. The transmission site is situated near Shangqiu, Henan Province at Coordinates: .
BPC broadcasts at 90 kW for 21 hours per day, with a 3-hour break from 05:00–08:00 (China Standard Time) daily (21:00–24:00 UTC). BPC includes both conventional amplitude modulated time code and additional spread-spectrum time code, about which little is known.
- "Low-frequency radio time signals". Cl.cam.ac.uk. Retrieved 2011-10-20.
- "Archived copy". Archived from the original on 2012-06-17. Retrieved 2013-03-16.CS1 maint: Archived copy as title (link)
- Feng, Ping; Wu, Guichen; Bai, Yan; Ding, Xiaofeng (August 2010), Tan, Jiubin; Wen, Xianfang (eds.), "Additional spread spectrum modulation timing method in BPC", Sixth International Symposium on Precision Engineering Measurements and Instrumentation. Proceedings of the SPIE, Proceedings of SPIE, 7544: 75441X–75441X–6, Bibcode:2010SPIE.7544E..68F, doi:10.1117/12.885845