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.[1], 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[1] at 34°27′25″N 115°50′13″E / 34.457°N 115.837°E.[2]
BPC broadcasts at 90 kW for 21 hours per day, with a 3-hour break from 05:00–08:00 (China Standard Time) daily[2] (21:00–24:00 UTC). BPC includes both conventional amplitude modulated time code and additional spread-spectrum time code, about which little is known.[3]
References
- ^ "Low-frequency radio time signals". Cl.cam.ac.uk. Retrieved 2011-10-20.
- ^ a b http://www.time.ac.cn/serve/e_c.htm
- ^ 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
External links
- 低频时码授时, from the National Time Service Center, Chinese Academy of Sciences