Practical RF Handbook, 4th Edition

Appendix 12

Worldwide minimum external noise levels

The figures reproduced below give the minimum levels of external noise ever likely to be encountered at a terrestrial receiving site. They are thus a useful guide to the receiver designer, in that there is, in general, no point in designing a receiver to have a noise level much lower than that to be expected from a reasonably efficient aerial system. (The only exception is where, for some special purpose, a very inefficient aerial must be used, e.g. a buried antenna servicing an underground bunker.)

The figures cover the whole frequency range of radio frequencies with which this book is concerned, 10 kHz to 1 GHz, and beyond. The report from which they are reproduced also covers frequencies ...