Estimating the size of a radio quiet zone for the radio astronomy service

	Estimating the size of a radio quiet zone for the radio astronomy service
	Peng, Bo; Han, Wenjun
刊名	EXPERIMENTAL ASTRONOMY
	2009-12-01
卷号	27 期号:1-2 页码:109-120
关键词	Astronomical techniques Astronomical phenomena and seeing Data analysis and techniques
英文摘要	The size of a radio quiet zone (RQZ) is largely determined by transmission losses of interfering signals, which can be divided into free space loss and diffraction loss. The free space loss is dominant. The diffraction loss presented in this paper is described as unified smooth spherical and knife edge diffractions, which is a function of minimum path clearance. We present a complete method to calculate the minimum path clearance. The cumulative distribution of the lapse rate of refractivity (g(n)), between the earth surface and 1 km above, is studied by using Chinese radio climate data. Because the size of an RQZ is proportional to g(n), the cumulative distribution of g(n) can be used as an approximation for the size of the RQZ. When interference originates from mobile communication or television transmissions at a frequency of 408 MHz, and (g(n)) over bar is 40 N/km, where the refractivity N = (n - 1)x10(6), the size of the RQZ would be 180 km for a mobile source or 210 km for a television source, with a probability in the range of 15-100% in different months and for different stations. When speaking of the size of an RQZ, the radius in the case of a circular zone is implied. It results that a size of an RQZ is mainly influenced by transmission loss rather than effective radiated power. In the case where the distance between an interfering source and a radio astronomical observatory is about 100 km, at a frequency of 408 MHz, the allowable effective radiated power of the interfering source should be less than -30 dBW with a probability of about 85% for (g(n)) over bar equals 40 N/km, or -42 dBW with a probability less than 1% for (g(n)) over bar equals 80 N/km.
收录类别	SCI
语种	英语
WOS记录号	WOS:000272029400008
内容类型	期刊论文
源URL	[http://ir.bao.ac.cn/handle/114a11/7963]
专题	国家天文台_射电天文研究部
作者单位	CAS, Natl Astron Observ, Beijing 100012, Peoples R China
推荐引用方式 GB/T 7714	Peng, Bo,Han, Wenjun. Estimating the size of a radio quiet zone for the radio astronomy service[J]. EXPERIMENTAL ASTRONOMY,2009,27(1-2):109-120.
APA	Peng, Bo,&Han, Wenjun.(2009).Estimating the size of a radio quiet zone for the radio astronomy service.EXPERIMENTAL ASTRONOMY,27(1-2),109-120.
MLA	Peng, Bo,et al."Estimating the size of a radio quiet zone for the radio astronomy service".EXPERIMENTAL ASTRONOMY 27.1-2(2009):109-120.