Location:Home > Engineering science > Detection Technology and Automation > The Research of Radio and Television Timing System on the Basis of Beidou Satellite and ZigBee Commu
Details
Name

The Research of Radio and Television Timing System on the Basis of Beidou Satellite and ZigBee Commu

Downloads: []
Author
Tutor: LingYouZhu
School: Anhui University of Engineering
Course: Detection Technology and Automation
Keywords: COMPASS,GLONASS,ZigBee communication technology,radio television,timing,DS3232,c
CLC: TN948
Type: Master's thesis
Year:  2011
Facebook Google+ Email Gmail Evernote LinkedIn Twitter Addthis

not access Image Error Other errors

Abstract:
Standard Time, which plays an important role in the radio television system, is a prerequisite for securing the broadcasting of the radio television. Currently, the satellite timing technology can be achieved by relying on the U.S. global satellite navigation system (GPS), the Russian Global Navigation Satellite System (GLONASS) or the Chinese Compass Navigation Satellite System (COMPASS). At this stage, China¡¯s radio and television center often make use of GPS timing to obtain the standard time, but the GPS timing provides no other ways and it is not self-control for us, which not only suffers from poor short-term stability, but also the security is not strong enough. Moreover, there is a certain distance between the application of China COMPASS and the foreign satellite navigation and positioning system, especially in the civilian level. It is far behind the industrialized and market-oriented level, which is not commensurate with the third position in the world that put into a practical application of satellite navigation and positioning system. With our own self-control "Beidou" navigation and positioning system to obtain the benchmark time, the standard CCTV and radio time for secondary timing source for the calibration of the local time, you can completely get rid of the dependence on thee GPS Timing.There are many devices, which attributed within the radio and television center building, which demand for standard time. Time for all the building has to be accurate and synchronized, so it requires network management group. The existing broadcast management system is mainly based on wired network which requires the laying of cables. Its wiring complexity and interference with the original embedded pipeline provide the inconvenience for the future maintenance. With the development of wireless communications technology, it provides the possibility of establishing a smooth and reliable wireless network. ZigBee communication technology is just surging in recent years, which is low-cost, low power consumption, simple, flexible and with good development prospects. With such technology, the time accuracy and the synchronization for the radio and television center can be achieved.Main innovation points for this paper:(1) With our own self-control "Beidou" navigation and positioning system to obtain the benchmark time, the standard CCTV and radio time for secondary timing source for the calibration of the local time, it improves the security of the radio and television broadcast system.(2) The second pulse signal the Beidou time receiver output is of great random error, but there is no cumulative error; the high-precision crystal oscillator¡¯s clock signal doesn¡¯t generate random error while the accumulated error is relatively small in a short period of time. Based on the characteristics of the two errors, the error mathematical model is established, through seeking the round part of the dynamic average of the counts generated by two adjacent Beidou second pulses within a period of time, the method of generating accurate clock signal by using the high-precision crystal oscillator to modify the Beidou second pulse¡¯s random error online after the elimination of the Beidou pseudo-second signals is put forward. The high-precision clock signal output device is developed according to this method and the device is applied to the synchronization field of radio and television broadcast industry successfully.(3) ZigBee wireless communication technology is used in radio and television timing system, which helps to send the exact time of the satellite system to the clock node, then the synchronization of the radio and television center is achieved. Such System is a wireless Internet with no wires, thus it improves the mobility of the clock node in the radio and television center.(4) A secondary data compensation method is proposed based on the temperature-compensated clock chip DS3232 to solve the crystal frequency deviation of the temperature.Currently, there is no footprint within the application region with the combination of Beidou timing technology and ZigBee communication technology. With the Beidou navigation positioning system timing and ZigBee¡¯s wireless networking, this paper combines such two kinds of cutting-edge technology together to achieve the synchronization of the accurate time for the radio and television center. The study possesses great significance for the monopoly of the foreign satellites timing system over China and for securing our country¡¯s information.
Related Dissertations
Last updated
Sponsored Links
Home |About Us| Contact Us| Feedback| Privacy | copyright | Back to top