Apparatus for modulating the output signal of a converter
US4450564A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 4, 1981 |
| Grant date | May 22, 1984 |
| Priority date | — |
| Expiry date | Sep 4, 2001 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B10/564
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
Apparatus for modulating the output signal of a converter for converting electric signals into other signals, for example optical signals. An analog signal is applied to a subtraction device (6) the output signal of which controls a limiter (7). The binary output signal thereof controls the semiconductor laser diode (1) which is coupled to a photo-sensitive detector (3) for producing a feedback signal. After being amplified in a broad-band amplifier (9) and integrated in an integrator (13), this feedback signal is applied to the subtraction device (6), so that the feedback signal is subtracted from the analog signal. Variations in the optical output signal due to a non-linear conversion characteristic of the laser diode (1) and due to an optical retroaction of the fibre (2) on the laser diode, as well as output noise and signal-dependent amplitude variations, are reduced by the negative feedback.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.