Optically efficient high dynamic range electro-optic modulator
US5781327A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 19, 1996 |
| Grant date | Jul 14, 1998 |
| Priority date | — |
| Expiry date | Aug 19, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F2203/19
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An electro-optic modulator and a method for its use, in which an optical carrier is effectively suppressed for transmission of a radio-frequency (rf) modulating signal over an optical communication link, to provide improved demodulator performance. A carrier component is recovered from the modulator, amplified, and reused, to minimize the effect of optical carrier losses. In one embodiment of the invention, a modulator (10) with complementary output ports (20 and 22) generates a carrier-suppressed output (FIG. 2B) containing rf sidebands from one port (20) and a strong carrier component (FIG. 2C) from the other output port (22). The carrier component is filtered in a residual sideband filter (14), amplified in an optical amplifying medium (12) and returned to the modulator (10) as its carrier input. In a second embodiment of the invention, a modulator (30) with a single output port produces rf sidebands and a suppressed carrier component (FIG. 4A), all of which are amplified in an optical amplifying medium (32) and coupled to an optical circulator (34), which, in cooperation with a narrowband filter (36), separates the rf sidebands from the amplified carrier component, the latter b…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.