Passive Bearing Finder Report No. 2. Signal-to-Noise Ratio of the R-C Coupled Band Pass Amplifier
Abstract
A theoretical analysis was carried out to evaluate the possibility of appreciably improving the signal-to-noise ratio of the Passive Bearing Finder amplifier by simple adjustment of the R-C time constants. It is shown that the frequency response of the R-C coupled amplifier may be closely approximated by a simple function completely determined by the values of two frequency parameters. These two parameters are determined by the specification of a significant pair of operating characteristics (such as the cut-off frequencies) or may be derived from three circuit constants (the two stage-time-constants and the number of stages). Expressions are derived for integrated noise output and steady-state, signal-to-noise ratio in terms of the noise and signal input and the two parameters of the response function. The types of noise considered are white noise, inverse frequency noise, and a combination of the two. A procedure is indicated for combining the results of a transient analysis with the expressions for noise output to obtain peak-to-peak-signal to RMS noise output. Application of results to the present periodic PBF amplifier shows that circuit constants are sufficiently close to the values for optimum signal-to-noise ratio.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 19, 1950
- Accession Number
- AD1214407
Entities
People
- J. W. Tucker
Organizations
- United States Naval Research Laboratory