Handbook on Radio Astronomy
Hide / Show Abstract

Handbook on Radio Astronomy

The Handbook on Radio Astronomy has been developed by experts of Working Party 7D of ITU-R Study Group 7 (Science Services) that is responsible for radio astronomy. This Handbook is not intended as a source book on radio astronomy, but rather deals with such aspects of radio astronomy that are relevant to frequency coordination as the management of radio spectrum usage in order to minimize interference between radiocommunication services.

Click to Access: 
    http://oecd.metastore.ingenta.com/content/pub-809847c8-en.pdf
  • PDF
  • http://www.keepeek.com/Digital-Asset-Management/oecd/science-and-technology/handbook-on-radio-astronomy_pub/809847c8-en
  • READ
 
Chapter
 

Sharing the radio astronomy bands with other services You do not have access to this content

English
Click to Access: 
    http://oecd.metastore.ingenta.com/content/pub-809847c8-93b6e50f-en.pdf
  • PDF
  • http://www.keepeek.com/Digital-Asset-Management/oecd/science-and-technology/handbook-on-radio-astronomy_pub/809847c8-93b6e50f-en
  • READ
Author(s):
ITU

Hide / Show Abstract

Most radio astronomy bands are shared with active services, which transmit. Such sharing is particularly difficult for radio astronomy, which is a passive service and is very sensitive to interference. Because of the great distances of astronomical sources, the pfd levels of the emissions under investigation are often 100 dB or more below those of man-made transmissions near the radio observatory. The strength and characteristics of the astronomical signals are determined by laws of nature and are beyond the control of the radio astronomer. Furthermore, because of the experimental nature of the science the radio astronomer is often unable to know in advance what the characteristics of the emissions will be. These factors make radio astronomy particularly vulnerable to interference. Interference can be damaging not only if it is strong and obliterates the astronomical signals, but also if it is weak. An insidious danger to radio astronomy lies in the interference which is just below the power level at which it can be recognized in individual measurements, and which is present for a large fraction of the total time. In this case there may be no means during the experiment of detecting that interference has occurred, and the subsequent results could contain serious errors.