Programmable analog transversal filter
US4034199A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 8, 1975 |
| Grant date | Jul 5, 1977 |
| Priority date | — |
| Expiry date | Dec 8, 1995 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D84/891
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A programmable analog transversal filter is disclosed for processing analog signals and comprising a charge-coupled device (CCD) for receiving a series of discrete analog signals to be delayed by increasing periods and applied to the outputs of the CCD, and a plurality of MNOS memory devices coupled to the taps of the CCD and programmed so that the output of a CCD tap is multiplied by a particular factor. In turn, the outputs of the MNOS memory devices are summed to provide an output signal ##EQU1## where W.sub.k is the weighting factor associated the k.sup.th MNOS memory device. The weighting factors are set into the system by varying the threshold voltage of the corresponding MNOS device. Positive and negative weighting factors are implemented by using first and second MNOS memory elements for each tap of the CCD, whereby depending upon the program incorporated into the system, one of the first and second MNOS memory devices is programmed to give either a positive weighting factor and the other MNOS memory device a negative weighting factor. Further, a reiterative method of setting the weights into the MNOS memory device is used to compare the system output indicative of the weig…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.