DocumentCode :
1293135
Title :
High frequency noise figure — A function of fα or fT ?
Author :
Thornton, J.W.
Author_Institution :
Philco Corporation, Lansdale Division, Lansdale, Penna
Issue :
1
fYear :
1963
fDate :
5/1/1963 12:00:00 AM
Firstpage :
68
Lastpage :
71
Abstract :
There has been some question in the past as to whether fα or fT should be used as the frequency criterion in determining transistor high frequency noise figure. This report is based on the following equation for noise figure as derived by Nielsen:1 ![F = 1 + {r_{b}^{\\prime } \\over r_{g}} + {r_{e} \\over 2r_{g}} + {{({r}_g+{r}_{b}^{\\prime } + {r}_e)^2} \\over {2r_{e}, r_g , \\beta _o}} \\left [1 + {(f/f_a)^2 \\over 1-\\alpha _o}\\right]. \\eqno{\\hbox {(1)}}](/images/tex/22457.gif)
Results show rather conclusively that fα should be used and not fT , for the frequency range from approximately 40 to 300 mc. These results apply specifically to the diffused base 2N1742 transistor. Conclusions have been drawn by comparing (1) the degree to which theoretical fα -noise figure correlates with measured noise figure to (2) the degree to which theoretical fT -noise figure correlates with measured noise figure
Results show rather conclusively that ffLanguage :
English
Journal_Title :
Broadcast and Television Receivers, IEEE Transactions on
Publisher :
ieee
ISSN :
0018-9308
Type :
jour
DOI :
10.1109/TBTR1.1963.6312106
Filename :
6312106
Link To Document :
