Noise parameter determination method
AssigneeCascade Microtech, Inc.
InventorAndrew C. Davidson
Life of this patent
Estimating the term…
Abstract
A method of determining a receiver's noise parameters by measuring one noise power for a first source noise temperature and a plurality of noise powers for another source noise temperature, all at known different source reflection coefficients.
Claims6
A method of determining the four parameters of a noise characterization equation which describes a receiver's noise performance as a function of the receiver's source termination, comprising the steps of:
- (a) measuring the receiver's noise power for each of four different known source terminations having a first noise temperature, and thereby determining a set of first noise power measurements;
- (b) measuring the receiver's noise power for a further known source termination having a second noise temperature, and thereby determining another noise power measurement;
- (c) determining a respective relative gain for each of said source terminations;
- (d) determining a respective ratio for each of said set of first noise power measurements to said respective relative gains;
- (e) substituting each of said respective ratios in said noise characterization equation, and thereafter calculating the four parameters in a form where two of said parameters are scaled by a constant;
- and
- (f) utilizing said further noise power measurement to determine said constant.
A method of determining the parameters of the noise equation F.sub.S =F.sub.min +(R.sub.n /G.sub.S).multidot..vertline.Y.sub.S-Y.sub.opt .vertline..sup.2 which describes a receiver's noise performance as a function of the receiver's source admittance Y.sub.S, comprising the steps of:
- (a) measuring the receiver's noise power for each of four different known source terminations having a first noise temperature, resulting in a set of first noise power measurements;
- (b) measuring the receiver's noise power for a second noise temperature, resulting in another noise power measurement;
- (c) determining a respective relative gain for each of said source terminations;
- (d) determining a respective ratio for each of said set of first noise power measurements to said respective, relative gains;
- (e) substituting each of said respective ratios in said noise characterization equation, and thereafter calculating the parameters Y.sub.opt =G.sub.S +jB.sub.S, and the parameters F.sub.min and R.sub.n scaled by a constant k;
- and
- (f) utilizing said further noise power measurement to determine said constant.
Dependencies are inferred from the claim text.