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], beginning April 25, 2002.

BPC transmits a time signal on 68.5 kHz, which can be used for synchronizing radio controlled clocks. 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 / 34.457; 115.837.[2]

BPC broadcasts at 90 kW for 20 hours per day, with a 4-hour break from 05:00–09:00 China Standard Time daily (21:00–01:00 UTC).[3] BPC includes both a conventional amplitude modulated time code transmitted during the first 400  of each second, and an additional phase modulated spread-spectrum time code transmitted during the last 600 ms of each second, about which little is known.[4]

  1. ^ "Low-frequency radio time signals". Cl.cam.ac.uk. Retrieved 2011-10-20.
  2. ^ "::时间服务::". Archived from the original on 2012-06-17. Retrieved 2013-03-16.
  3. ^ 西安高华科技有限公司 (2020-01-10). "河南商丘BPC电波塔发播时间公布" (in Chinese). Archived from the original on 2021-07-29. Retrieved 2021-07-29.
  4. ^ Feng, Ping; Wu, Guichen; Bai, Yan; Ding, Xiaofeng (August 2010), "Additional spread spectrum modulation timing method in BPC" (PDF), in Tan, Jiubin; Wen, Xianfang (eds.), Sixth International Symposium on Precision Engineering Measurements and Instrumentation, Proceedings of SPIE, vol. 7544, pp. 75441X–75441X–6, Bibcode:2010SPIE.7544E..1XF, doi:10.1117/12.885845, S2CID 110865336 The paper appears to be describing a proposed addition to the time signal, but the tenses are confusing and sometimes implies that the addition has been implemented.