Correction to Friis Noise Factors
Abstract
The signal-to-noise ratio of a multistage cascade network is often estimated using Friis formulas for noise factors (or the noise figures in decibel). In this letter, the correct formulas to calculate the stage-wise noise factors and the total noise factor in terms of the stage-wise noise factors of an n-stage cascade network are derived. A comparison of our derived formulas for noise factors with Friis's formulas is presented. Contrary to Friis's total noise factor in terms of the stage-wise noise factors, we define the actual total noise factor of the n-stage cascade network as the product of its stage-wise noise factors.
- Publication:
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arXiv e-prints
- Pub Date:
- September 2022
- DOI:
- 10.48550/arXiv.2209.00287
- arXiv:
- arXiv:2209.00287
- Bibcode:
- 2022arXiv220900287B
- Keywords:
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- Electrical Engineering and Systems Science - Signal Processing;
- Physics - Applied Physics;
- Physics - Instrumentation and Detectors
- E-Print:
- 5 pages, 2 figures