Measurement of signal quality
US6389111B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 2, 1998 |
| Grant date | May 14, 2002 |
| Priority date | — |
| Expiry date | Nov 2, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M2201/40
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A test stimulus includes two signals RR, S. Signal S is transmitted to a customer equipment interface and over a system under test to a complementary remote apparatus. The test apparatus has two inputs processed by a number of functional elements. The first input is the reference signal RR. The other input is a corresponding test signal R′ generated at remote test apparatus as a test signal R, identical with reference signal RR, and transmitted over the system under test via the customer interface. These two versions of the same test signal are compared. Firstly, the signals RR, R′ are processed by a psycho-acoustic model, the output of which is transmitted to a perceptual layer, and then to a conversion unit which also receives a further input from a non-optimum loudness rating unit. The output from the conversion unit is transmitted to a signal quality determination unit, which also receives an input from the customer equipment interface. The non-optimum loudness rating unit processes inputs from the customer equipment interface and signal generator. During an iterative process, the signal generator receives feedback control from the signal quality determination unit.…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.