Method and apparatus for determining the noise power ratio (NPR) of a unit under test
US4608647A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 24, 1983 |
| Grant date | Aug 26, 1986 |
| Priority date | — |
| Expiry date | Oct 24, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/2834
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The present invention describes a method and apparatus for determining the noise power ratio (NPR) of a unit under test (UUT). According to the method, a frequency domain representation of a desired test spectrum is generated by prompting an operator to input selected parameters to a general purpose digital computer. The desired test spectrum includes a notch of predetermined depth. The frequency domain representation is transformed into an input signal sequence by an inverse Fast Fourier Transform algorithm, the sequence defining a time domain representation thereof. The input signal sequence is then applied to the unit under test. An output signal sequence defining a time domain representation of a measured test spectrum is received from the unit under test and transformed back into a frequency domain representation. This frequency domain representation includes a notch whose depth is normalized in dB to determine the noise power ratio of the unit under test.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.