JPS6410741A - Optical heterodyne detection communicating method - Google Patents

Optical heterodyne detection communicating method

Info

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
Application number
JP62164009A
Other languages
Japanese (ja)
Inventor
Shuntaro Yamazaki
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
NEC Corp
Original Assignee
NEC Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by NEC Corp filed Critical NEC Corp
Priority to JP62164009A priority Critical patent/JPS6410741A/en
Publication of JPS6410741A publication Critical patent/JPS6410741A/en
Pending legal-status Critical Current

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  • 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.
JP62164009A 1987-07-02 1987-07-02 Optical heterodyne detection communicating method Pending JPS6410741A (en)

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)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH05227103A (en) * 1991-11-14 1993-09-03 Nec Corp Optical communication method

Cited By (1)

* Cited by examiner, † Cited by third party
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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