A Note on Noise Factor Measurement

Download or read book A Note on Noise Factor Measurement written by Wave Propagation Laboratory and published by . This book was released on 1969 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: The definition of noise factor, F, is reviewed and the mathematical bases for several methods of measuring noise factor are presented. Error analyses are given to determine: (1) the noise source temperatures, which minimize the noise factor measurement error, (2) an analytic expression for the expected error in F as measured by the CW methods, and (3) an analytic expression for the expected error in F as measured by the Y-Factor Method. A hypothetical receiver (of assumed characteristics) is used as a comparative example to elevate the errors to be expected in F as measured by the CW Method and by the Y-Factor Method. The importance of bandwidth as a criterion of receiver performance is stressed. The effect on the measured F produced by a change in receiver gain-bandwidth produced by a change in received gain-bandwidth produced by a change is receiver gain-bandwidth produce is considered briefly. A preliminary calculation of the source temperatures actually seen by the receiver input completes the report. The appendix is a procedural outline for measuring a receiver's noise factor by: (1) automatic noise factor meter (ANFM), (2) CW Method, and (3) Y-Factor Methods. This outline indicates the characteristics required of the test equipment and tells how to obtain the necessary data.