JPS6410741A - Optical heterodyne detection communicating method - Google Patents
Optical heterodyne detection communicating methodInfo
- Publication number
- JPS6410741A JPS6410741A JP62164009A JP16400987A JPS6410741A JP S6410741 A JPS6410741 A JP S6410741A JP 62164009 A JP62164009 A JP 62164009A JP 16400987 A JP16400987 A JP 16400987A JP S6410741 A JPS6410741 A JP S6410741A
- Authority
- JP
- Japan
- Prior art keywords
- intermediate frequency
- signal
- frequency signal
- light
- differential detection
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Optical Communication System (AREA)
Abstract
PURPOSE:To set a modulation index at a comparatively small value by providing a light receiving part with a differential detection circuit, the delay time of which is n-bits, and inputting a first intermediate frequency signal to it, and demodulating a signal by a second intermediate frequency signal, appearing in the output of it. CONSTITUTION:The first intermediate frequency signal is obtained by transmitting an FSK modulated signal light from a light transmitting part, and receiving the FSK modulated signal light by the light receiving part, and the first intermediate frequency signal is inputted to the differential detection circuits 5, 6, the delay time of which is n-bits (n is one or larger integer), and a demodulated signal is obtained by demodulating the second intermediate frequency signal, appearing in the output of the differential detection circuits 5, 6. Accordingly, because the considerable part of the influence of the FM noise of a light source is absorbed by the differential detection circuits 5, 6, this influence comes difficult to appear in the demodulation of the signal. Thus, the dependency of a required modulation index upon the spectrum width of the light source and a bit rate can be extremely reduced, and in addition, the modulation index can be set at a comparatively small value.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP62164009A JPS6410741A (en) | 1987-07-02 | 1987-07-02 | Optical heterodyne detection communicating method |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP62164009A JPS6410741A (en) | 1987-07-02 | 1987-07-02 | Optical heterodyne detection communicating method |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS6410741A true JPS6410741A (en) | 1989-01-13 |
Family
ID=15785034
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP62164009A Pending JPS6410741A (en) | 1987-07-02 | 1987-07-02 | Optical heterodyne detection communicating method |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS6410741A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH05227103A (en) * | 1991-11-14 | 1993-09-03 | Nec Corp | Optical communication method |
-
1987
- 1987-07-02 JP JP62164009A patent/JPS6410741A/en active Pending
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH05227103A (en) * | 1991-11-14 | 1993-09-03 | Nec Corp | Optical communication method |
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