# Accession Number:

## AD0261516

# Title:

## A THEORY OF NOISY TWO-PORT NETWORKS

# Descriptive Note:

## Technical rept. no. 5 on Microwave Noise,

# Corporate Author:

## CORNELL UNIV ITHACA N Y

# Personal Author(s):

# Report Date:

## 1961-05-15

# Pagination or Media Count:

## 97.0

# Abstract:

IN ORDER TO OVEROME THE LAC OF SPECIFIC INFORMATION ABOUT THE NOISE PROPERTIES OF ACTIVE ELEMENTS, A STUDY OF NOISY ELECTRICAL NETWORKS IS PRESENTED, WHICH USES A MODEL THAT DESCRIBES THE TOTAL NETWORK NOISE BY MEANS OF EQUIVALENT NOISE GENERATORS AT THE SEVERAL ACCESSIBLE TERMINAL-PAIRS. The parameters of the generators are shown to be obtainable by measurements performed at these terminal pairs. Both time- and frequency-domain representations are given. A frequency-domain correlation function is introduced, which is shown to provide a complete description of the correlation between equvalent noise generators, and an experimental procedure for determining this function is presented. Two performance criteria for assessing the degree to which noise disturbs the desired operation of a network are discussed. The noise measure, which is related to the conventional noise figure, is shown to be a useful gauge of network performance when the applied input signal is not noisy. Minimizing the noise measure at each frequency of a frequency band is not always possible, so that it use is restriced to single-frequency amplifiers. Use of the meansquare error of the network as a performance criterion is discussed. Author

# Descriptors:

- *COMMUNICATION AND RADIO SYSTEMS
- *INFORMATION THEORY
- *ELECTRICAL NETWORKS
- ADMITTANCE
- CIRCUITS
- ELECTRICAL IMPEDANCE
- ERRORS
- INTEGRAL TRANSFORMS
- LINEAR SYSTEMS
- MATHEMATICAL ANALYSIS
- MATRICES(MATHEMATICS)
- MEASUREMENT
- MEASUREMENT
- MICROWAVE NETWORKS
- NOISE GENERATORS
- SIMULATION
- SOURCES
- STATISTICAL FUNCTIONS