Channel quality
US5761212A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 20, 1995 |
| Grant date | Jun 2, 1998 |
| Priority date | — |
| Expiry date | Oct 20, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B20/182
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A measurement circuit is provided to obtain data for monitoring the quality of performance from a digital read channel. Elements of the digital read channel including a sequence detector are incorporated into an integrated circuit together with the measurement circuit. The measurement circuit relates digitized samples of readback data from a magnetic storage device to surrounding samples so that particular samples can be collected in accordance with their surroundings. The circuit includes a programmable time window which can be repeatedly opened for data collection. The circuit is designed to collect various types of data including the bit error rate, sample value, squared sample error, squared gain error, squared timing error, and the occurrences of sample error when it is outside an acceptable programmable threshold. The measurement circuit includes a signal generator for producing a test pattern that is first stored and then read to produce the digitized readback sample values. The measurement circuit also includes a conversion circuit for converting the test pattern to a sequence of expected sample values in accordance with a state machine model of the sequence detector. The s…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.