JP4065884B2 - Method for configuring wavelength tunable light source, wavelength tunable light source device, and wavelength division multiplexing optical transmission device using the light source device - Google Patents

Description

  The present invention relates to a light source for optical communication that outputs a specific wavelength, and more particularly to a wavelength tunable light source that can control an output wavelength from the outside, and a wavelength division multiplexing optical transmission device using this light source.

  In the wavelength division multiplexing optical transmission apparatus, each channel connecting the transmission end and the reception end is divided according to the wavelength of the light source. Therefore, the light source that outputs a specific wavelength is the main element of the wavelength division multiplexing optical transmission apparatus.

  The light source used in the wavelength division multiplexing optical transmission device must stabilize the output wavelength and set the adjacent mode suppression ratio (SMSR) to minimize interference with adjacent channels (crosstalk). It needs to be bigger. Also, it is necessary to increase the output power, and the line width must be reduced in order to minimize the influence of chromatic dispersion and the like.

  A typical example of a conventional light source that satisfies the above-described requirements is a distributed feedback laser diode (DFB LD). However, since the distributed feedback laser diode is complicated and expensive, the output light of a borad-band light source that outputs in a wide wavelength band can be reduced by using an optical filter (optical filter). A spectrum-slicing optical communication device that is divided and used through a filter) has been studied.

  Light sources used in spectrum-splitting optical communication devices include light emitting diodes (LEDs), super-luminescent diodes (SLDs), and light that emits spontaneous emission (ASE). Incoherent light sources (ILS: Incoherent Light Source) such as amplifier light sources are typical, and when a spectrum splitting type optical communication device is realized using such incoherent light sources, distributed feedback laser diodes are used. It is more economical than the case and wavelength control is easy.

  However, the light emitting diode and the super light emitting diode do not have sufficient output power, and the optical amplifier light source requires an external modulator that has relatively high output power but high cost.

In other words, Patent Document 1 (Invention name: System for spectrum-sliced fiber amplifier light for multi-channel wavelength-division-multiplexed applications) is intended to realize an economical optical amplifier light source used in a wavelength division multiplexing optical transmission device. Then, the spontaneously emitted light of the optical amplifier is spectrally divided and externally modulated, and Patent Document 2 (invention name: Wavelength division multiplexing passive optical network including broadcast overlay) proposes a method of spectrally dividing the directly modulated LED. ing.
US Pat. No. 5,440,417 US Pat. No. 5,694,234

  However, Patent Document 1 requires an expensive external modulator, and Patent Document 2 has a disadvantage that the output power is not sufficient.

  On the other hand, a wavelength tunable light source that can arbitrarily vary the output wavelength by external control can increase the flexibility of the wavelength division multiplexing optical transmission device and provide various functions.

  The distributed feedback laser diode described above can change the output wavelength by controlling the temperature, but it has a variable wavelength range within the 1270-1600 nm wavelength band, which is the low loss band of general silica optical fiber. There is a disadvantage of about several nanometers.

  Therefore, wavelength tunable light sources using external cavities have been mainly studied in the past, but wavelength tunable light sources using external synthesizers are expensive and complex devices to vary their output wavelengths. Cost.

  The present invention has been devised to solve such problems, and includes a wavelength tunable light source including a Fabry-Perot laser diode and a wavelength division multiplexing optical transmission device using the light source. provide.

  Fabry-Perot laser diodes have the advantages of low cost and relatively high output power, but mode hopping and mode as a multi-mode light source that oscillates multiple modes simultaneously. A partition noise (mode partition noise) was generated, and it was not used in a wavelength division multiplexing optical transmission apparatus.

  However, Korea Patent No. 1003256870000 (Title of Invention: Light source for wavelength division multiplexing optical communication using wavelength locking phenomenon of Fabry-Perot laser diode by injected incoherent light, registration date: February 8, 2002 As shown in (2), by injecting a narrowband incoherent light into the Fabry-Perot laser diode from the outside, the output wavelength can be fixed to match the injected incoherent light. This makes it possible to increase the output power from a specific wavelength, thereby obtaining a large adjacent mode suppression rate.

  The wavelength tunable light source according to the present invention fixes the output wavelength of the Fabry-Perot laser diode to the narrowband incoherent light injected from the outside as described above, and sets the wavelength of the incoherent light injected from the outside. The purpose is to vary the output wavelength by controlling.

  The adjacent mode suppression rate, noise characteristics, output power, and the like of the above-described wavelength tunable light source are optimized by appropriately controlling the temperature of the Fabry-Perot laser diode.

  The wavelength tunable light source described above can perform not only external modulation but also direct modulation, so the number of optical transmitters can be reduced, and one multiplexer / demultiplexer is used for the output of one incoherent light source that outputs in a wide wavelength band. Then, after the spectrum is divided into a large number of incoherent light beams in a narrow band, it is injected into a large number of Fabry-Perot laser diodes at the same time, thereby realizing an economical wavelength division multiplexing optical transmission device.

  A method of constructing a wavelength tunable light source for injecting narrowband incoherent light from the outside into the Fabry-Perot laser diode according to the present invention and matching the output wavelength of the Fabry-Perot laser diode with the narrowband incoherent light Is characterized in that the output wavelength of the Fabry-Perot laser diode is varied by varying the wavelength of the incoherent narrowband light that is injected.

  The method of constructing a wavelength tunable light source according to the present invention is characterized in that the adjacent mode suppression rate, noise characteristics, and output power are controlled by controlling the temperature of the Fabry-Perot laser diode.

  The method of constructing a wavelength tunable light source according to the present invention is characterized in that the adjacent mode suppression rate, noise characteristics, and output power are controlled by controlling a current applied to the Fabry-Perot laser diode.

  A wavelength tunable light source device according to the present invention includes a non-coherent light source that outputs broadband incoherent light, a variable pass band, and a non-coherent light output from the non-coherent light source. A pass-band variable filter that passes only narrow-band incoherent light and a Fabry-Perot laser that outputs a wavelength that matches the wavelength of the incoherent light when the narrow-band incoherent light is injected from the outside. A diode, and is connected between the passband variable filter and the Fabry-Perot laser diode, and transmits the narrowband incoherent light input through the passband variable filter to the Fabry-Perot laser diode; And an optical circulator that transmits from the Perot laser diode to the outside.

  The wavelength division multiplexing optical transmission apparatus according to the present invention outputs an incoherent light source that outputs broadband incoherent light and an optical signal input to the first terminal to the second terminal and inputs to the second terminal. Optical circulator for outputting the optical signal to the third terminal, one common terminal and 2N input / output terminals, each having a different wavelength between the common terminal and each of the 2N input / output terminals One 2Nx1 multiplexer / demultiplexer that transmits a plurality of optical signals, and a specific wavelength transmitted between the common terminal of the multiplexer / demultiplexer and the odd numbered input / output terminals between the first terminal and the second terminal. Only the optical signal is transmitted, the optical signals of other wavelengths are blocked, and the signal transmitted between the common terminal of the multiplexer / demultiplexer and the even-numbered input / output terminal between the first terminal and the third terminal Only the optical signal of wavelength A first wavelength alternating coupler and a second wavelength alternating coupler that transmit and block optical signals of other wavelengths, and when incoherent light of a narrow band is injected from the outside, the wavelength of the incoherent light An N number of Fabry-Perot laser diodes that output matching wavelengths and an N number of optical receivers that convert an input optical signal into an electrical signal and output the electrical signal; Are connected to the Fabry-Perot laser diode, the even-numbered terminals of the multiplexer / demultiplexer are connected to the optical receiver, and the common terminal of the multiplexer / demultiplexer is the first wavelength alternator. The second terminal of the first wavelength alternator is connected to the second terminal of the optical circulator, and the first terminal of the optical circulator. The child is connected to the incoherent light source, the third terminal of the optical circulator is connected to the second terminal of the second wavelength alternator, and the third wavelength of the second wavelength alternator and the first wavelength alternation The third terminal of the coupler is connected.

  The wavelength division multiplexing optical transmission apparatus according to the present invention further includes a multiplexer / demultiplexer temperature control device for controlling the temperature of the multiplexer / demultiplexer.

  The wavelength division multiplexing optical transmission apparatus according to the present invention further includes a laser diode driving circuit that directly modulates the Fabry-Perot laser diode.

  The wavelength division multiplexing optical transmission apparatus according to the present invention further includes a laser diode temperature control device for controlling the temperature of the Fabry-Perot laser diode.

  The wavelength division multiplexing optical transmission apparatus according to the present invention outputs an incoherent light source that outputs broadband incoherent light and an optical signal input to the first terminal to the second terminal and inputs to the second terminal. An optical circulator for outputting the optical signal to the third terminal, one common terminal and 2N input / output terminals, and the common terminal and each of the 2N input / output terminals are different. One 2Nx1 multiplexer / demultiplexer that transmits an optical signal of a wavelength, and between the first terminal and the second terminal, is transmitted between the common terminal of the multiplexer / demultiplexer and the 1st to Nth input / output terminals. An optical signal having a specific wavelength is transmitted to cut off an optical signal having another wavelength, and a signal transmitted between the common terminal of the multiplexer / demultiplexer and the N + 1 to 2N terminals between the first terminal and the third terminal. Transmit optical signal of wavelength A first wavelength division multiplexer and a second wavelength division multiplexer that block optical signals of other wavelengths, and when a narrow-band incoherent light is injected from the outside, a wavelength that matches the wavelength of the incoherent light is output. N Fabry-Perot laser diodes and N optical receivers for converting an input optical signal into an electrical signal and outputting the electrical signal, and the first to N terminals of the multiplexer / demultiplexer are respectively connected to the Fabry Connected to a Perot laser diode, N + 1 to 2N terminals of the multiplexer / demultiplexer are connected to the optical receiver, and a common terminal of the multiplexer / demultiplexer is connected to a first terminal of the first wavelength division multiplexer The second terminal of the first wavelength division multiplexer is connected to the second terminal of the optical circulator; The first terminal of the optical circulator is connected to the incoherent light source, the third terminal of the optical circulator is connected to the second terminal of the second wavelength division multiplexer, and the third terminal of the second wavelength division multiplexer and the A third terminal of the first wavelength division multiplexer is connected.

  The wavelength division multiplexing optical transmission apparatus according to the present invention further includes a multiplexer / demultiplexer temperature control device for controlling the temperature of the multiplexer / demultiplexer.

  The wavelength division multiplexing optical transmission apparatus according to the present invention further includes a laser diode driving circuit that directly modulates the Fabry-Perot laser diode.

  The wavelength division multiplexing optical transmission apparatus according to the present invention further includes a laser diode temperature control device for controlling the temperature of the Fabry-Perot laser diode.

  The wavelength division multiplexing optical transmission apparatus according to the present invention outputs an incoherent light source that outputs broadband incoherent light and an optical signal input to the first terminal to the second terminal and inputs to the second terminal. An optical circulator for outputting the optical signal to the third terminal, one common terminal, and N input / output terminals, each of which is different between the common terminal and each of the N input / output terminals. One Nx1 multiplexer / demultiplexer for transmitting an optical signal of a wavelength, and a common terminal of the multiplexer / demultiplexer within a free spectral range of the multiplexer / demultiplexer between the first and second terminals Transmits only optical signals of a specific wavelength transmitted between N input / output terminals and blocks optical signals of other wavelengths, and between the first and second terminals between the first and third terminals. Optical signal transmitted to A first wavelength division multiplexer, a second wavelength division multiplexer, and N third wavelength division multiplexers that transmit optical signals separated from each other by an independent spectral region and block optical signals of other wavelengths, and the multiplexer / demultiplexer. N Fabry-Perot laser diodes that output a wavelength that matches the wavelength of the incoherent light when a narrowband incoherent light within a specific free spectral range is injected from the outside, N optical receivers for converting an input optical signal into an electrical signal and outputting the electrical signal, and each terminal of the multiplexer / demultiplexer is connected to a first terminal of a third wavelength division multiplexer, respectively, The second terminal of the wavelength division multiplexer is connected to the Fabry-Perot laser diode, respectively, and the third wavelength division multiplexer. Are connected to the optical receiver, a common terminal of the multiplexer / demultiplexer is connected to a first terminal of the first wavelength division multiplexer, and a second terminal of the first wavelength division multiplexer is connected to the optical receiver. Connected to the second terminal of the circulator, the first terminal of the optical circulator is connected to the incoherent light source, the third terminal of the optical circulator is connected to the second terminal of the second wavelength division multiplexer, and The third terminal of the two wavelength division multiplexer is connected to the third terminal of the first wavelength division multiplexer.

  The wavelength division multiplexing optical transmission apparatus according to the present invention further includes a multiplexer / demultiplexer temperature control device for controlling the temperature of the multiplexer / demultiplexer.

  The wavelength division multiplexing optical transmission apparatus according to the present invention further includes a laser diode driving circuit that directly modulates the Fabry-Perot laser diode.

  The wavelength division multiplexing optical transmission apparatus according to the present invention further includes a laser diode temperature control device for controlling the temperature of the Fabry-Perot laser diode.

  The wavelength division multiplexing optical transmission apparatus according to the present invention outputs an incoherent light source that outputs broadband incoherent light and an optical signal input to the first terminal to the second terminal and inputs to the second terminal. An optical circulator for outputting the optical signal to the third terminal, one common terminal, and N input / output terminals, each of which is different between the common terminal and each of the N input / output terminals. An Nx1 multiplexer / demultiplexer that transmits an optical signal of a wavelength, an optical signal input terminal, and an optical signal output terminal, and an electrical signal to which an optical signal input from the input terminal is applied And an external modulator driving device that drives the external modulator and receives an electrical signal, each of the multiplexer / demultiplexer terminals respectively Fabry Perot Connected to a laser diode, a common terminal of the multiplexer / demultiplexer is connected to a second terminal of the optical circulator, a first terminal of the optical circulator is connected to the incoherent light source, and a third terminal of the optical circulator Is connected to an input terminal of the external modulator, and the external modulator is connected to the external modulator driving device.

  The wavelength division multiplexing optical transmission apparatus according to the present invention further includes an optical receiver connected to an input terminal of the external modulator driving device, and the optical receiver converts the input optical signal into an electrical signal. Then, it is converted into an optical signal again and output.

  The wavelength division multiplexing optical transmission apparatus according to the present invention further includes a multiplexer / demultiplexer temperature control device for controlling the temperature of the multiplexer / demultiplexer.

  The wavelength division multiplexing optical transmission apparatus according to the present invention further includes N polarization controllers connected between the multiplexer / demultiplexer terminal and the Fabry-Perot laser diode.

  The wavelength division multiplexing optical transmission apparatus according to the present invention further includes a polarization controller connected between the third terminal of the optical circulator and the external modulator.

  The wavelength division multiplexing optical transmission apparatus according to the present invention further includes a laser diode temperature control device for controlling the temperature of the Fabry-Perot laser diode.

  The optical transmission device using the light source according to the present invention can reduce the cost of the light source and not only reduce the cost per channel, but also facilitate the expansion of the optical transmission device and the communication network because of the large output power.

  The wavelength division multiplexing optical transmission apparatus according to the present invention is configured to be able to input or output wavelength division multiplexed optical signals simultaneously through one optical fiber, and halves the number of optical fibers required for optical communication. Can be reduced.

  Hereinafter, the present invention will be described in detail with reference to the drawings illustrating embodiments thereof. Referring to FIG. 1, a wavelength tunable light source according to the present invention includes an incoherent light source (ILS) 101, a passband variable filter (TBPF: Tunable Band-Pass Filter) 102 having a variable passband, an optical circulator. (OC: Optical Circulator) 103 and a Fabry-Perot Laser Diode (FPLD) 104.

  The incoherent light source 101 outputs broadband incoherent light. As the incoherent light source 101, an optical fiber amplifier, a semiconductor optical amplifier, a light emitting diode, a super light emitting diode, or the like that outputs spontaneous emission (ASE: Amplified Spontaneous Emission) is used.

  The Fabry-Perot laser diode 104 does not include an isolator or the like so that incoherent light is efficiently injected.

  When incoherent light is output from the incoherent light source 101, the component that has passed through the passband of the passband variable filter 102 is injected into the Fabry-Perot laser diode 104 through the optical circulator 103.

  If no incoherent light is injected from the outside, the Fabry-Perot laser diode 104 outputs multiple modes (multi-mode output), but if a narrowband incoherent light is injected from the outside, the Fabry-Perot laser diode 104 Of the oscillation modes of the diode 104, another mode having a wavelength different from that of the light injected from the outside is suppressed, and the output is relatively increased in a mode in which the wavelength matches that of the light injected from the outside. Accordingly, an output signal having a spectrum similar to that of a single mode laser is output through an optical circulator 103 connected to a Fabry-Perot laser diode 104.

  Since the output wavelength of the incoherent light source 101 matches the wavelength of the narrowband incoherent light injected into the Fabry-Perot laser diode 104, the center wavelength of the passband of the passband variable filter 102 is adjusted. Variable.

  On the other hand, the oscillation wavelength for each mode of the Fabry-Perot laser diode 104 varies depending on the temperature of the Fabry-Perot laser diode 104. Therefore, when the wavelength of incoherent light injected from the outside is fixed, by controlling the temperature of the Fabry-Perot laser diode 104, it is possible to output in a specific mode that matches the wavelength of incoherent light injected from the outside. Adjust to increase power.

  Using such characteristics, the current of the Fabry-Perot laser diode 104 is adjusted to control the adjacent mode suppression rate, noise characteristics, output power, and the like of the output of the wavelength tunable light source. Further, by adjusting the bias current applied to the Fabry-Perot laser diode 104, the adjacent mode suppression rate, noise characteristics, output power, and the like of the output of the wavelength tunable light source may be controlled.

  The output power of the tunable light source varies depending on the current applied to the Fabry-Perot laser diode 104. Therefore, not only the output of the wavelength tunable light source may be modulated using an external modulator, but also the current applied to the Fabry-Perot laser diode 104 may be modulated and directly modulated.

  When an appropriate current is applied to the Fabry-Perot laser diode 104, the tunable light source is polarized and output, but the reflected component of the injected incoherent light may not be polarized.

  Utilizing such characteristics, a polarization controller and a polarizer are further added to the output end of the optical circulator 103 to improve the extinction ratio of the modulated optical signal. That is, after adding a modulation signal by the Fabry-Perot laser diode 104, adjusting the polarization controller so that the output power of the wavelength tunable light source becomes maximum, the extinction ratio of the output of the wavelength tunable light source is also maximized. become.

  In the light source according to the present invention, the optical circulator 103 is used to minimize the loss of injected light and the loss of the optical signal output from the Fabry-Perot laser diode 104 at the same time. Further, a light source having similar characteristics can be obtained by replacing the optical circulator 103 with a low-cost optical power coupler.

  FIG. 2 is a block diagram showing an experimental apparatus for measuring the performance of the wavelength tunable light source according to the present invention. The incoherent light source (broadband light source) 101 in FIG. 1 is a two-stage erbium-doped fiber amplifier (EDFA) 201, and the passband variable filter 202 is a Fabry-Perot etalon filter (Farby-Perot filter). etalon filter) is used. The two-stage erbium-doped optical fiber amplifier 201 outputs spontaneous emission light (ASE) which is incoherent light having a bandwidth (1530 nm-1560 nm) of about 30 nm or more.

  The Fabry-Perot etalon filter can pass only narrow-band incoherent light of spontaneous emission, the 3-dB bandwidth is about 2.5 GHz, and the passband center wavelength can be varied by applying voltage.

  The power of the incoherent light input to the Fabry-Perot laser diode 204 via the optical circulator 203 is -2 dBm, the threshold current of the Fabry-Perot laser diode 204 used is 10 mA, and the bias of 17 mA A current is applied. An optical spectrum analyzer (OSA) 205 measures an optical spectrum.

  FIG. 3 is a diagram showing an optical spectrum measured using the apparatus of FIG. 2, and FIG. 3 (a) shows an output spectrum of the Fabry-Perot laser diode 204 measured in a state where no spontaneous emission light is injected. 3 (b) shows the spectrum of the narrowband incoherent light injected into the Fabry-Perot laser diode 204, and FIG. 3 (c) shows the above-mentioned incoherent light injected in FIG. 3 (b). The output spectrum of a wavelength variable light source is shown.

  The center wavelengths of the incoherent light injected into the Fabry-Perot laser diode 204 are 1530 nm, 1545 nm, and 1560 nm, and the Fabry-Perot laser diode 204 is set so that the adjacent mode suppression rate is maximized for each wavelength. Set the temperature.

  FIG. 3 (a) shows three spectra. As described above, when the wavelength of incoherent light injected into the Fabry-Perot laser diode 204 is 1530 nm, 1545 nm, and 1560 nm, respectively, the temperature is adjusted so that the adjacent mode suppression rate is maximized, 2 shows the output spectrum of the Fabry-Perot laser diode 204 measured after removing the incoherent light injected in 1).

  After injection of incoherent light, Fabry-Perot laser diode 204 outputs a specific wavelength according to the wavelength of the injected incoherent light. The measured adjacent mode suppression rates are all over 30 dB and the output power is about 0 dBm. Therefore, it can be seen that the wavelength tunable light source according to the present invention outputs a wavelength with a narrow line width having a wavelength variable region of about 30 nm or more.

  The Fabry-Perot laser diode used in the wavelength tunable light source according to the present invention plays a role of suppressing noise intensity of incoherent light injected in the process of fixing the wavelength.

  That is, “Signal-to-noise ratio” according to IEEE Photonic Technology Letters, vol.1, No.1, p. 94-96, 1997, by Jae-Seung Lee. Incoherent light that has been spectrally split as presented in "measurement of a 2.5-Gb / s spectrum-sliced incoherent light channel" has a high noise intensity, which causes a large beat at the optical receiver. Noise (beat noise) is generated. Such beat noise increases the beat error rate in the spectrum splitting optical communication device and degrades performance.

  The wavelength tunable light source according to the present invention, after injecting a spectrum-divided incoherent light source into the Fabry-Perot laser diode, is output from the Fabry-Perot laser diode. (noise intensity) is reduced sufficiently and output.

  FIG. 4 is a diagram showing an optical spectrum measured by another optical filter using the apparatus of FIG. FIG. 5 shows a configuration diagram of an experimental apparatus for eye diagram measurement for confirming such characteristics.

  In the experimental apparatus shown in FIG. 5A, the narrowband incoherent light output from the two-stage erbium-doped optical fiber amplifier 501 and passed through the passband variable filter 502 is modulated by an external modulator (EM) 503. Thereafter, an eye diagram is measured using an oscilloscope 504, which corresponds to a conventional spectral division type optical transmission apparatus.

  The experimental apparatus of FIG. 5B injects incoherent light output from the two-stage erbium-doped optical fiber amplifier 505 and passed through the passband variable filter 506 through the optical circulator 507 into the Fabry-Perot laser diode 508, After directly modulating the Fabry-Perot laser diode 508, an eye diagram is measured using an oscilloscope 509, which corresponds to the wavelength tunable light source according to the present invention.

  For the passband variable filters 502 and 506, a Fabry-Perot etalon filter is used, and the bandwidth of the Fabry-Perot etalon filter is approximately 2.5 GHz.

5A and 5B, the modulation speed is 622 Mb / s, and the length of the pseudo random binary sequence (PRBS) applied to the external modulator 503 and the Fabry-Perot laser diode 508 is 2. ³¹ -1.

  FIGS. 6A and 6B are respective eye diagrams measured using the experimental apparatus of FIGS. 5A and 5B. Referring to the eye diagrams of FIGS. 6A and 6B, it can be seen that the noise intensity of incoherent light is suppressed when the wavelength variable light source according to the present invention is used.

  As described above, the wavelength tunable light source according to the present invention is variously used for the wavelength division multiplexing optical transmission apparatus.

FIG. 7 is a diagram showing a first embodiment of a wavelength division multiplexing optical transmission apparatus using a light source according to the present invention. N first group optical signals (λ) wavelength division multiplexed through one optical fiber are shown. ₁ , λ ₃ ,..., Λ _2N-1 ), and wavelength division multiplexed N second group optical signals (λ ₂ , λ ₄ ,..., Λ _2N ) input through the optical fiber. Receive.

  Referring to FIG. 7, the wavelength division multiplexing optical transmission apparatus according to the present invention includes N Fabry-Perot laser diodes 701a, 701b,..., 701n, N laser diode driving circuits 702a, 702b,. , 703n, N optical receivers 704a, 704b,..., 704n, one 2Nx1 multiplexer / demultiplexer 705, one multiplexer / demultiplexer temperature controller 706, two The first and second wavelength alternate couplers (Interleaver) 707 and 708 are composed of one optical circulator 709 and one incoherent light source 710.

  The 2Nx1 multiplexer / demultiplexer 705 separates the wavelength division multiplexed optical signal input to the common terminal for each wavelength and outputs the separated signals to the 2N input / output terminals or to the 2N input / output terminals, respectively. The input wavelengths are wavelength division multiplexed with other optical signals and output to the common terminal.

The wavelengths of the first group optical signals (λ ₁ , λ ₃ ,..., Λ _2N-1 ) and the second group optical signals (λ ₂ , λ ₄ ,..., Λ _2N ) are set to different wavelength bands. The first group of optical signals (λ ₁ , λ ₃ ,..., Λ _2N-1 ) is between the common terminal of the 2Nx1 multiplexer / demultiplexer 705 and the odd-numbered terminals (1, 3,..., 2N−1). , And the second group optical signal (λ ₂ , λ ₄ ,..., Λ _2N ) passes between the common terminal of the _2N × 1 multiplexer / demultiplexer 705 and the even-numbered terminals (2, 4,..., 2N). Communicated.

  The incoherent light source 710 outputs broadband incoherent light. The optical circulator 709 outputs the optical signal input to the first terminal to the second terminal, and outputs the optical signal input to the second terminal to the third terminal.

A first group optical signal (λ ₁ , λ ₃ ,..., Λ _2N-1 ) is transmitted between the first and second terminals of the first and second wavelength alternating couplers 707, 708 to the second group. The optical signals (λ ₂ , λ ₄ ,..., Λ _2N ) are blocked, and the second group optical signals (λ ₂ , λ ₄ ,..., Λ _2N ) are transmitted between the first terminal and the third terminal. Then, the first group optical signals (λ ₁ , λ ₃ ,..., Λ _2N-1 ) are blocked.

  The optical transmission apparatus 700 configured as described above is connected as follows. The odd numbered terminals of the 2Nx1 multiplexer / demultiplexer 705 are connected to Fabry-Perot laser diodes 701a, 701b,..., 701n, respectively, and the even numbered terminals are connected to optical receivers 704a, 704b,.

  The common terminal of the 2Nx1 multiplexer / demultiplexer 705 is connected to the first terminal of the first wavelength alternating coupler 707, the second terminal of the first wavelength alternating coupler 707 is connected to the second terminal of the optical circulator 709, and the optical circulator. The first terminal of 709 is connected to the incoherent light source 710 and the third terminal is connected to the second terminal of the second wavelength alternating coupler 708.

  The third terminal of the first wavelength alternating coupler 707 is connected to the third terminal of the second wavelength alternating coupler 708, and the first terminal of the second wavelength alternating coupler 708 becomes the output terminal of the optical transmission device 700.

  The optical transmission device 700 operates as follows. First, the incoherent light source 710 generates and outputs a broadband incoherent light, which is input to the first terminal of the optical circulator 709 and input to the second terminal of the first wavelength alternating coupler 707 via the second terminal. . The first wavelength alternator 707 outputs a part of the inputted broadband incoherent light to the first terminal. The signal is input from the first terminal of the first wavelength alternator 707 to the common terminal of the 2Nx1 multiplexer / demultiplexer 705 and then output to the odd numbered terminal of the 2Nx1 multiplexer / demultiplexer 705.

2Nx1 multiplexer / demultiplexer 705 is input to odd-numbered terminals of Fabry-Perot laser diodes 701a, 701b,..., 701n, and Fabry-Perot laser diodes 701a, 701b,. the first group optical signal that matches the wavelength _{(λ 1, λ 3, ...} , λ 2N-1) outputs, a first group optical signals _{(λ 1, λ 3, ...} , λ 2N-1) is 2Nx1 multiplexer / After being multiplexed by the demultiplexer 705, it is input to the first terminal of the first wavelength alternating coupler 707.

The first group optical signals (λ ₁ , λ ₃ ,..., Λ _2N-1 ) multiplexed and input to the first wavelength alternator 707 are output to the second terminal and then the second optical circulator 709. The signal is input to the second terminal of the second wavelength alternating coupler 708 via the terminal and the third terminal, and is output to the first terminal of the second wavelength alternating coupler 708.

Further, the second group optical signal (λ ₂ , λ ₄ ,..., Λ _2N ) input to the first terminal of the second wavelength alternating coupler 708 is output to the third terminal, and the first wavelength alternating coupler 707. Is input to the third terminal of the 2Nx1 multiplexer / demultiplexer 705 and then output to the first terminal. The second group optical signals (λ ₂ , λ ₄ ,..., Λ _2N ) input to the common terminal are output to the even-numbered terminals of the 2Nx1 multiplexer / demultiplexer 705 and then connected to the even-numbered terminals, respectively. , 704n are received by the optical receivers 704a, 704b,.

  The optical transmission device 700 includes N laser diode driving circuits 702a, 702b,..., 702n that generate optical signals modulated by the Fabry-Perot laser diodes 701a, 701b,. , 701b,..., 701n, N laser diode temperature controllers 703a, 703b,..., 703n and 2Nx1 multiplexer / demultiplexer 705.

FIG. 8 is a diagram showing a second embodiment of a wavelength division multiplexing optical transmission apparatus using a light source according to the present invention. N third group optical signals (λ ₁ ) wavelength-division multiplexed through one optical fiber. , Λ ₂ ,..., Λ _N ) and input through the optical fiber N wavelength-division multiplexed N fourth group optical signals (λ _{N + 1} , λ _{N + 2} ,..., Λ _2N ) Receive.

  Referring to FIG. 8, the wavelength division multiplexing optical transmission apparatus according to the present invention is modulated with N Fabry-Perot laser diodes 801a, 801b,..., 801n, and Fabry-Perot laser diodes 801a, 801b,. N laser diode drive circuits 802a, 802b,..., 802n for generating optical signals, N laser diode temperature control devices 803a, 803b for controlling the temperature of each Fabry-Perot laser diode 801a, 801b,. .., 803n, N optical receivers 804a, 804b,. The first and second wavelength division multiplexers 807 and 808 are composed of one optical circulator 809 and one incoherent light source 810.

  The 2Nx1 multiplexer / demultiplexer 805 separates the wavelength division multiplexed optical signal input to the common terminal for each wavelength and outputs it to the 2N input / output terminals, or to the 2N input / output terminals. The input wavelengths are wavelength division multiplexed with other optical signals and output to the common terminal.

The wavelengths of the third group optical signals (λ ₁ , λ ₂ ,..., Λ _N ) and the fourth group optical signals (λ _{N + 1} , λ _{N + 2} ,..., Λ _2N ) are set to different wavelength bands. The third group optical signal (λ ₁ , λ ₂ ,..., Λ _N ) is transmitted between the common terminal of the 2Nx1 multiplexer / demultiplexer 805 and the 1st to _Nth terminals, and the fourth group optical signal (λ _{N + 1} , λ _{N + 2} ,..., λ _2N ) are transmitted between the common terminal of the _2N × 1 multiplexer / demultiplexer 805 and the terminals N + 1 to 2N.

  The incoherent light source 810 outputs broadband incoherent light. The optical circulator 809 outputs the optical signal input to the first terminal to the second terminal, and outputs the optical signal input to the second terminal to the third terminal.

A third group optical signal (λ ₁ , λ ₂ ,..., Λ _N ) is transmitted between the first terminal and the second terminal of the first and second wavelength division multiplexers 807 and 808 to transmit a fourth group optical signal (λ _{N +1} , λ _{N + 2} ,..., Λ _2N ) and the fourth group optical signal (λ _{N + 1} , λ _{N + 2} ,..., Λ _2N ) is transmitted between the first terminal and the third terminal. The third group optical signals (λ ₁ , λ ₂ ,..., Λ _N ) are blocked.

  The optical transmission apparatus 800 having the above-described configuration is connected as follows. The 1N terminals of the 2Nx1 multiplexer / demultiplexer 805 are connected to Fabry-Perot laser diodes 801a, 801b,..., 801n, respectively, and the N + 1 to 2N terminals are connected to optical receivers 804a, 804b,. Connected.

  The common terminal of the 2Nx1 multiplexer / demultiplexer 805 is connected to the first terminal of the first wavelength division multiplexer 807. The second terminal of the first wavelength division multiplexer 807 is connected to the second terminal of the optical circulator 809. The first terminal is connected to the incoherent light source 810 and the third terminal is connected to the second terminal of the second wavelength division multiplexer 808, respectively.

  The third terminal of the first wavelength division multiplexer 807 and the third terminal of the second wavelength division multiplexer 808 are connected, and the first terminal of the second wavelength division multiplexer 808 becomes the output terminal of the optical transmission device 800.

  The optical transmission device 800 operates as follows. First, the output of the incoherent light source 810 is input to the first terminal of the optical circulator 809, and then input to the second terminal of the first wavelength division multiplexer 807 via the second terminal. The first wavelength division multiplexer 807 outputs a part of the input broadband incoherent light to the first terminal. After being input from the first wavelength division multiplexer 807 to the common terminal of the 2Nx1 multiplexer / demultiplexer 805, it is output to the 1st to Nth terminals of the 2Nx1 multiplexer / demultiplexer 805, respectively.

2Nx1 multiplexer / demultiplexer 805 inputs to Fabry-Perot laser diodes 801a, 801b,..., 801n, and Fabry-Perot laser diodes 801a, 801b,. The group optical signals (λ ₁ , λ ₂ ,..., Λ _N ) are output, and the third group optical signals (λ ₁ , λ ₂ ,..., Λ _N ) are multiplexed by the 2Nx1 multiplexer / demultiplexer 805 and then The signal is input to the first terminal of the one wavelength division multiplexer 807.

The third group optical signals (λ ₁ , λ ₂ ,..., Λ _N ) input to the first wavelength division multiplexer 807 are output to the second terminal and then to the second and third terminals of the optical circulator 809. Then, the signal is input to the second terminal of the second wavelength division multiplexer 808 and output to the first terminal of the second wavelength division multiplexer 808.

Further, the fourth group optical signal (λ _{N + 1} , λ _{N + 2} ,..., Λ _2N ) input to the first terminal of the second wavelength division multiplexer 808 is output to the third terminal and again the first wavelength division. After being input to the third terminal of the multiplexer 807 and output to the first terminal, it is input to the common terminal of the 2Nx1 multiplexer / demultiplexer 805. The signals input to the common terminals are output to the N + 1 to 2N terminals of the 2N × 1 multiplexer / demultiplexer 805 and then received by the optical receivers 804a, 804b,.

  The optical transmission apparatus 800 includes N laser diode drive circuits 802a, 802b,..., 802n that generate optical signals modulated by the Fabry-Perot laser diodes 801a, 801b,. , 801b,..., 801n, N laser diode temperature controllers 803a, 803b,..., 803n, and a multiplexer / demultiplexer temperature controller 806 for controlling the temperature of the 2Nx1 multiplexer / demultiplexer 805.

FIG. 9 is a diagram showing a third embodiment of a wavelength division multiplexing optical transmission apparatus using a light source according to the present invention. N fifth group optical signals (λ) wavelength division multiplexed through one optical fiber are shown. ₁ , λ ₂ ,..., Λ _N ), and wavelength division multiplexed N sixth group optical signals (λ _{N + 1} , λ _{N + 2} ,..., Λ _2N ) input through the optical fiber. Receive.

  Referring to FIG. 9, the wavelength division multiplexing optical transmission apparatus according to the present invention is modulated by N Fabry-Perot laser diodes 901a, 901b,..., 901n, and each Fabry-Perot laser diode 901a, 901b,. N laser diode drive circuits 902a, 902b,..., 902n for generating optical signals, N laser diode temperature controllers 903a, 903b for controlling the temperature of each Fabry-Perot laser diode 901a, 901b,. ..., 903n, N optical receivers 904a, 904b, ..., 904n, one Nx1 multiplexer / demultiplexer 905, multiplexer / demultiplexer temperature controller 906 for controlling the temperature of Nx1 multiplexer / demultiplexer 905 One wavelength division multiplexer 907, one second wavelength division multiplexer 908, N third wavelength division multiplexers 909a,. 909b, comprised of 909N, one optical circulator 910 and one non-coherent light source 911.

  The Nx1 multiplexer / demultiplexer 905 divides the wavelength division multiplexed optical signal input to the common terminal into each wavelength and outputs it to each of the N input / output terminals, or to the N input / output terminals. Each wavelength is wavelength-division multiplexed to another optical signal and output to a common terminal. Signal transmission between the common terminal and each input / output terminal has a characteristic of being repeated with a wavelength interval that is an integral multiple of the independent spectral region.

The wavelengths of the fifth group optical signals (λ ₁ , λ ₂ ,..., Λ _N ) and the sixth group optical signals (λ _{N + 1} , λ _{N + 2} ,..., Λ _2N ) are set to different wavelength bands. Nx1 multiplexer / demultiplexer 905 is transmitted between the common terminal and the 1st to Nth terminals, respectively, but the fifth group optical signal (λ ₁ , λ ₂ ,..., Λ _N ) and the sixth group optical signal (λ _{N +1} , λ _{N + 2} ,..., Λ _2N ) each have a wavelength spacing that is an integral multiple of the independent spectral region of the _{N × 1} multiplexer / demultiplexer 905.

  The incoherent light source 911 outputs broadband incoherent light. The optical circulator 911 outputs the optical signal input to the first terminal to the second terminal, and outputs the optical signal input to the second terminal to the third terminal.

A fifth group optical signal (λ ₁ , λ ₂ ,..., Λ _N ) is sent between the first and second terminals of the first, second and third wavelength division multiplexers 907, 908, 909 a, 909 b,. transmitted to the sixth group optical signal _{(λ N + 1, λ N} + 2, ..., λ 2N) blocked, between the No. 1 terminal and third terminal sixth group optical signal (λ _{N + 1,} λ _{N +2} ,..., Λ _2N ) are transmitted to block the fifth group optical signals (λ ₁ , λ ₂ ,..., Λ _N ).

  The optical transmission device 900 having the above-described configuration is connected as follows. N terminals of the Nx1 multiplexer / demultiplexer 905 are connected to the third wavelength division multiplexers 909a, 909b,..., 909n, respectively, and the second terminals of the third wavelength division multiplexers 909a, ..., 909b, 909n are Fabry-Perot lasers. , 901n are connected to the diodes 901a, 901b,..., 901n, and the third terminal is connected to the optical receivers 904a, 904b,.

  The common terminal of the Nx1 multiplexer / demultiplexer 905 is connected to the first terminal of the first wavelength division multiplexer 907. The second terminal of the first wavelength division multiplexer 907 is connected to the second terminal of the optical circulator 910. The first terminal is connected to the incoherent light source 911, and the third terminal is connected to the second terminal of the second wavelength division multiplexer 908. The third terminal of the first wavelength division multiplexer 907 and the third terminal of the second wavelength division multiplexer 908 are connected, and the first terminal of the second wavelength division multiplexer 908 becomes the output terminal of the optical transmission apparatus 900.

  The optical transmission apparatus 900 operates as follows. First, the light is input from the incoherent light source 911 to the first terminal of the optical circulator 910 and then to the second terminal of the first wavelength division multiplexer 907 via the second terminal. The first wavelength division multiplexer 907 outputs a part of the output of the input incoherent light source 911 to the first terminal. After being inputted from the first wavelength division multiplexer 907 to the common terminal of the Nx1 multiplexer / demultiplexer 905, it is outputted to the N terminals of the Nx1 multiplexer / demultiplexer 905, respectively.

, 909n is input from the Nx1 multiplexer / demultiplexer 905 to the first terminal and output to the second terminal, and then input to the Fabry-Perot laser diodes 901a, 901b,. Each of the Fabry-Perot laser diodes 901a, 901b,..., 901n outputs a fifth group optical signal (λ ₁ , λ ₂ ,..., Λ _N ) that matches the wavelength of the input incoherent light. The optical signals (λ ₁ , λ ₂ ,..., Λ _N ) are wavelength-division multiplexed again by the Nx1 multiplexer / demultiplexer 905 via the wavelength division multiplexers 909a, 909b,. It is input to the 1st terminal of 907. The fifth group optical signals (λ ₁ , λ ₂ ,..., Λ _N ) input to the first wavelength division multiplexer 907 are output to the second terminal, and then connected to the second and third terminals of the optical circulator 910. Then, the signal is input to the second terminal of the second wavelength division multiplexer 908 and output to the first terminal of the second wavelength division multiplexer 908.

The sixth group optical signals (λ _{N + 1} , λ _{N + 2} ,..., Λ _2N ) input to the first terminal of the second wavelength division multiplexer 908 are output to the third terminal and again output to the first wavelength division multiplexer. The signal is input to the third terminal 907, output to the first terminal, and then input to the common terminal of the Nx1 multiplexer / demultiplexer 905. The sixth group optical signals (λ _{N + 1} , λ _{N + 2} ,..., Λ _2N ) input to the common terminal are output to the N terminals of the Nx1 multiplexer / demultiplexer 905, and then the third wavelength division. Input to the first terminal of the multiplexers 909a, 909b,.

The sixth group optical signals (λ _{N + 1} , λ _{N + 2} ,..., Λ _2N ) input to the third wavelength division multiplexers 909a, 909b,. After being output to the third terminal of 909n, it is received by the optical receivers 904a, 904b,.

  The optical transmission device 900 includes N laser diode driving circuits 902a, 902b,..., 902n that generate optical signals modulated by the Fabry-Perot laser diodes 901a, 901b,. , 901b,..., 901n, N laser diode temperature controllers 903a, 903b,..., 903n and Nx1 multiplexer / demultiplexer temperature controller 906 for controlling the temperature.

  FIG. 10 is a diagram showing a fourth embodiment of a wavelength division multiplexing optical transmission apparatus using a light source according to the present invention. Referring to FIG. 10, the wavelength division multiplexing optical transmission apparatus according to the present invention includes N Fabry-Perot laser diodes 1001a, 1001b,..., 1001n, and each Fabry-Perot laser diode 1001a, 1001b,. N laser diode temperature control devices 1002a, 1002b,..., 1002n to control, one Nx1 multiplexer / demultiplexer 1003, multiplexer / demultiplexer temperature control device 1004 to control the temperature of Nx1 multiplexer / demultiplexer 1003, one light A circulator 1005, one incoherent light source 1006, one external modulator 1007 and one external modulator driving circuit 1008 are included.

  The Nx1 multiplexer / demultiplexer 1003 separates the wavelength division multiplexed optical signal input to the common terminal into each wavelength and outputs it to the N input / output terminals, or to the N input / output terminals. Other optical signals are wavelength division multiplexed from the input wavelengths and output to the common terminal.

  The incoherent light source 1006 outputs broadband incoherent light. The optical circulator 1005 outputs the optical signal input to the first terminal to the second terminal, and outputs the optical signal input to the second terminal to the third terminal. The external modulator 1007 modulates an electrical signal into an optical signal.

  The optical transmission apparatus 1000 configured as described above is connected as follows. Fabry-Perot laser diodes 1001a, 1001b,..., 1001n are connected to the N terminals of the Nx1 multiplexer / demultiplexer 1003, respectively. The common terminal of the Nx1 multiplexer / demultiplexer 1003 is connected to the second terminal of the optical circulator 1005. The

  The first terminal of the optical circulator 1005 is connected to the incoherent light source 1006, and the third terminal of the optical circulator 1005 is connected to the external modulator 1007. The external modulator 1007 is connected to an external modulator driving circuit 1008 for driving the external modulator 1007, an electrical signal is input from the external modulator driving circuit 1008, and a modulated optical signal is output through the external modulator 1007. .

  The optical transmission apparatus 1000 operates as follows. First, the output of the incoherent light source 1006 is input to the first terminal of the optical circulator 1005, input to the common terminal of the Nx1 multiplexer / demultiplexer 1003 through the second terminal, and then N terminals of the Nx1 multiplexer / demultiplexer 1003. Are output respectively. Nx1 multiplexer / demultiplexer 1003 inputs to Fabry-Perot laser diodes 1001a, 1001b,..., 1001n, and each Fabry-Perot laser diode 1001a, 1001b,..., 1001n matches the wavelength of the input incoherent light Outputs an optical signal.

  Output from Fabry-Perot laser diodes 1001a, 1001b, ..., 1001n, multiplexed by Nx1 multiplexer / demultiplexer 1003, input to external modulator 1007 via optical circulator 1005, and external modulator 1007 input An electrical signal is modulated into an optical signal and output.

  The optical transmission device 1000 transmits an optical signal having one or more arbitrary wavelengths through an external modulator 1007 by controlling the current applied to each Fabry-Perot laser diode 1001a, 1001b,..., 1001n. Control to output.

The external modulator 1007 provided in the optical transmission apparatus 1000 according to the present invention uses either an electroabsorption modulator or a Mach-gender interferometer modulator using LiNbO ₃ .

  In addition, the temperature of N laser diode temperature control devices 1002a, 1002b,..., 1002n and Nx1 multiplexer / demultiplexer 1003 for controlling the temperature of each Fabry-Perot laser diode 1001a, 1001b,. A multiplexer / demultiplexer temperature controller 1004 for controlling is further provided.

  FIG. 11 is a diagram showing a fifth embodiment of a wavelength division multiplexing optical transmission apparatus using a light source according to the present invention. One polarization controller 1009 or N polarization controllers are included in the optical transmission apparatus 1000 of FIG. 1010a, 1010b,..., 1010n. The configuration of the other parts is the same as in FIG. 10, and the same reference numerals as those in FIG. When the characteristic of the external modulator 1007 used in the optical transmission device 1100 according to the present invention varies depending on the polarization, the input / output terminals of the Nx1 multiplexer / demultiplexer 1003 and the Fabry-Perot laser diodes 1001a, 1001b,. N polarization controllers 1010a, 1010b,..., 1010n are connected between them, or one polarization controller 1009 is connected between the external modulator 1007 and the third terminal of the optical circulator 1005.

  FIG. 12 is a diagram showing a sixth embodiment of a wavelength division multiplexing optical transmission apparatus using a light source according to the present invention, and is a configuration in which an optical receiver 1011 is further provided in the optical transmission apparatus 1000 of FIG. The configuration of the other parts is the same as in FIG. 10, and the same reference numerals as those in FIG.

  The optical receiver 1011 provided in the optical transmission apparatus 1200 according to the present invention having the above-described configuration converts an optical signal input from the outside into an electrical signal. By further including one optical receiver 1011, when an optical signal of a specific wavelength is input from the outside, the optical signal is converted into an electrical signal, and again, an optical signal of the same wavelength, one or two or more It can be reproduced or converted into an optical signal of another wavelength. At this time, the wavelength of the optical signal output through the external modulator 1007 can be varied by controlling the current applied to each Fabry-Perot laser diode 1001a, 1001b,..., 1001n.

  FIG. 13 is a diagram showing a seventh embodiment of a wavelength division multiplexing optical transmission apparatus using a light source according to the present invention. One polarization controller 1009 or N polarization controllers are included in the optical transmission apparatus 1000 of FIG. 1010a, 1010b,..., 1010n, and an optical receiver 1011. The configuration of the other parts is the same as in FIG. 10, and the same reference numerals as those in FIG. One polarization controller 1009 or N polarization controllers 1010a, 1010b,..., 1010n and the optical receiver 1011 provided in the optical transmission apparatus 1300 according to the present invention have the same reference numerals as those in FIGS. Therefore, the description of the configuration and operation is omitted.

It is a block diagram of the wavelength variable light source by this invention. It is a block diagram of the experimental apparatus for measuring the performance of the wavelength variable light source by this invention. It is a figure which shows the optical spectrum measured using the apparatus of FIG. It is a figure which shows the optical spectrum measured by another optical filter using the apparatus of FIG. It is a block diagram of the experimental apparatus for an eye diagram measurement. It is each eye diagram measured using the experimental apparatus of FIG. 1 is a diagram illustrating a first embodiment of a wavelength division multiplexing optical transmission apparatus using a light source according to the present invention. It is a figure which shows 2nd Example of the wavelength division multiplexing system optical transmission apparatus using the light source by this invention. It is a figure which shows 3rd Example of the wavelength division multiplexing system optical transmission apparatus using the light source by this invention. It is a figure which shows 4th Example of the wavelength division multiplexing system optical transmission apparatus using the light source by this invention. It is a figure which shows 5th Example of the wavelength division multiplexing system optical transmission apparatus using the light source by this invention. It is a figure which shows 6th Example of the wavelength division multiplexing system optical transmission apparatus using the light source by this invention. It is a figure which shows 7th Example of the wavelength division multiplexing system optical transmission apparatus using the light source by this invention.

Explanation of symbols

101,710,810,911,1006 Incoherent light source
102,202,502,506 Passband variable filter
103,203,507,709,809,910,1005 Optical circulator
104,204,508,701a-701n, 801a-801n, 901a-901n, 1010a-1010n Fabry-Perot laser diode
700,800,900,1000,1100 Optical transmission equipment
702a-702n, 802a-802n, 902a-902nLaser diode drive circuit
703a-703n, 803a-803n, 903a-903n, 1002a-1002n Laser diode temperature controller
704a-704n, 804a-804n, 904a-904n, 1011 Optical receiver
705,805 2Nx1 multiplexer / demultiplexer
706,806,906,1004 Multiplexer / demultiplexer temperature controller
707 1st wavelength alternating coupler
708 Second wavelength alternating coupler
807,907 First wavelength division multiplexer
808,908 Second wavelength division multiplexer
905,1003 Nx1 multiplexer / demultiplexer
909a-909n Third wavelength division multiplexer
1007 External modulator
1008 External modulator drive circuit
1009,1010a-1010n Polarization controller

Claims (22)

In a method of constructing a wavelength tunable light source that injects a narrowband incoherent light from the outside into a Fabry-Perot laser diode and matches the output wavelength of the Fabry-Perot laser diode with the narrowband incoherent light,
A method of varying the output wavelength of the Fabry-Perot laser diode by varying the wavelength of the narrowband incoherent light to be injected.   2. The method of constructing a wavelength tunable light source according to claim 1, wherein adjacent mode suppression rate, noise characteristics, and output power are controlled by controlling a temperature of the Fabry-Perot laser diode.   2. The method of configuring a wavelength tunable light source according to claim 1, wherein adjacent mode suppression rate, noise characteristics, and output power are controlled by controlling a current applied to the Fabry-Perot laser diode. An incoherent light source that outputs broadband incoherent light; and
A passband variable filter that allows the passband to be variable, and allows only non-coherent light in a narrow band within the passband to pass from incoherent light output from the incoherent light source,
A Fabry-Perot laser diode that outputs a wavelength that matches the wavelength of the incoherent light when the narrowband incoherent light is injected from the outside;
Connected between the passband variable filter and a Fabry-Perot laser diode, and transmits the narrowband incoherent light input through the passband variable filter to the Fabry-Perot laser diode, and the Fabry-Perot laser diode A wavelength tunable light source device comprising: an optical circulator that transmits light to the outside. An incoherent light source that outputs broadband incoherent light; and
An optical circulator that outputs an optical signal input to the first terminal to the second terminal and outputs an optical signal input to the second terminal to the third terminal;
One 2Nx1 multiplexer / demultiplexer having one common terminal and 2N input / output terminals and transmitting optical signals of different wavelengths between the common terminal and each of the 2N input / output terminals;
Between the first terminal and the second terminal, only the optical signal of a specific wavelength transmitted between the common terminal of the multiplexer / demultiplexer and the odd-numbered input / output terminal is transmitted, and the optical signals of other wavelengths are cut off. In addition, between the first terminal and the third terminal, only the optical signal of a specific wavelength transmitted between the common terminal of the multiplexer / demultiplexer and the input / output terminal of the even number is transmitted, and the optical signal of other wavelengths is transmitted. A first wavelength alternator and a second wavelength alternator,
N narrow Fabry-Perot laser diodes that output a wavelength that matches the wavelength of the incoherent light when narrowband incoherent light is injected from the outside;
And N optical receivers that convert an input optical signal into an electrical signal and output it,
The odd numbered terminals of the multiplexer / demultiplexer are respectively connected to the Fabry-Perot laser diode, the even numbered terminals of the multiplexer / demultiplexer are respectively connected to the optical receiver, and the multiplexer / demultiplexer common terminal Is connected to the first terminal of the first wavelength alternator, the second terminal of the first wavelength alternator is connected to the second terminal of the optical circulator, and the first terminal of the optical circulator is the non-interference The optical circulator, the third terminal of the optical circulator is connected to the second terminal of the second wavelength alternating coupler, and the third terminal of the second wavelength alternating coupler and the third terminal of the first wavelength alternating coupler. A wavelength division multiplexing optical transmission apparatus characterized by being connected to a terminal.   6. The wavelength division multiplexing optical transmission device according to claim 5, further comprising a multiplexer / demultiplexer temperature control device for controlling a temperature of the multiplexer / demultiplexer.   6. The wavelength division multiplexing optical transmission apparatus according to claim 5, further comprising a laser diode driving circuit that directly modulates the Fabry-Perot laser diode.   6. The wavelength division multiplexing optical transmission device according to claim 5, further comprising a laser diode temperature control device for controlling a temperature of the Fabry-Perot laser diode. An incoherent light source that outputs broadband incoherent light; and
An optical circulator that outputs an optical signal input to the first terminal to the second terminal and outputs an optical signal input to the second terminal to the third terminal;
One 2Nx1 multiplexer / demultiplexer having one common terminal and 2N input / output terminals, and transmitting optical signals of different wavelengths between the common terminal and each of the 2N input / output terminals; ,
Between the first terminal and the second terminal, an optical signal of a specific wavelength transmitted between the common terminal of the multiplexer / demultiplexer and the input / output terminals of Nos. 1 to N is transmitted to transmit optical signals of other wavelengths. Shut off and transmit optical signals of specific wavelengths transmitted between the common terminal of the multiplexer / demultiplexer and the N + 1 to 2N terminals between the 1st terminal and the 3rd terminal to cut off optical signals of other wavelengths A first wavelength division multiplexer and a second wavelength division multiplexer,
N Fabry-Perot laser diodes that output a wavelength that matches the wavelength of the incoherent light when narrowband incoherent light is injected from the outside;
N optical receivers for converting an input optical signal into an electrical signal and outputting the electrical signal,
The multiplexer / demultiplexer 1 to N terminals are connected to the Fabry-Perot laser diode, respectively. The multiplexer / demultiplexer N + 1 to 2N terminals are connected to the optical receiver, respectively. The common terminal is connected to the first terminal of the first wavelength division multiplexer, the second terminal of the first wavelength division multiplexer is connected to the second terminal of the optical circulator, and the first terminal of the optical circulator is the non-interference An optical circulator, a third terminal of the optical circulator is connected to a second terminal of the second wavelength division multiplexer, a third terminal of the second wavelength division multiplexer, and a third terminal of the first wavelength division multiplexer. A wavelength division multiplexing optical transmission apparatus characterized by being connected.   The wavelength division multiplexing optical transmission device according to claim 9, further comprising a multiplexer / demultiplexer temperature control device for controlling a temperature of the multiplexer / demultiplexer.   10. The wavelength division multiplexing optical transmission apparatus according to claim 9, further comprising a laser diode driving circuit that directly modulates the Fabry-Perot laser diode.   The wavelength division multiplexing optical transmission device according to claim 9, further comprising a laser diode temperature control device for controlling a temperature of the Fabry-Perot laser diode. An incoherent light source that outputs broadband incoherent light; and
An optical circulator that outputs an optical signal input to the first terminal to the second terminal and outputs an optical signal input to the second terminal to the third terminal;
An Nx1 multiplexer / demultiplexer having one common terminal and N input / output terminals, and transmitting optical signals of different wavelengths between the common terminal and each of the N input / output terminals; ,
A specific wavelength transmitted between the common terminal of the multiplexer / demultiplexer and the N input / output terminals within the free spectral range of the multiplexer / demultiplexer between the first terminal and the second terminal An optical signal that is separated from the optical signal transmitted between the first and second terminals by an independent spectral region is transmitted between the first and third terminals. A first wavelength division multiplexer, a second wavelength division multiplexer, and N third wavelength division multiplexers that transmit optical signals and block optical signals of other wavelengths;
When a narrow-band incoherent light within a free spectral range of the multiplexer / demultiplexer is injected from the outside, N Fabrys that output wavelengths that match the wavelength of the incoherent light are output. Perot laser diode,
N optical receivers for converting an input optical signal into an electrical signal and outputting the electrical signal,
Each terminal of the multiplexer / demultiplexer is connected to the first terminal of the third wavelength division multiplexer, and the second terminal of the third wavelength division multiplexer is connected to the Fabry-Perot laser diode, respectively. The third terminal of the multiplexer is connected to the optical receiver, the common terminal of the multiplexer / demultiplexer is connected to the first terminal of the first wavelength division multiplexer, and the second terminal of the first wavelength division multiplexer is Connected to the second terminal of the optical circulator, the first terminal of the optical circulator is connected to the incoherent light source, the third terminal of the optical circulator is connected to the second terminal of the second wavelength division multiplexer, and The third terminal of the second wavelength division multiplexer and the first wavelength division multiplexer Wavelength division multiplexing optical transmission apparatus characterized by third and the terminal is connected.   The wavelength division multiplexing optical transmission device according to claim 13, further comprising a multiplexer / demultiplexer temperature control device for controlling a temperature of the multiplexer / demultiplexer.   14. The wavelength division multiplexing optical transmission apparatus according to claim 13, further comprising a laser diode driving circuit that directly modulates the Fabry-Perot laser diode.   The wavelength division multiplexing optical transmission device according to claim 13, further comprising a laser diode temperature control device for controlling a temperature of the Fabry-Perot laser diode. An incoherent light source that outputs broadband incoherent light; and
An optical circulator that outputs an optical signal input to the first terminal to the second terminal and outputs an optical signal input to the second terminal to the third terminal;
An Nx1 multiplexer / demultiplexer having one common terminal and N input / output terminals, and transmitting optical signals of different wavelengths between the common terminal and each of the N input / output terminals; ,
An external modulator that has one optical signal input terminal and one optical signal output terminal, modulates an optical signal input from the input terminal with an applied electrical signal, and outputs the modulated optical signal to the output terminal;
An external modulator driving device for driving the external modulator and receiving an electrical signal;
Each terminal of the multiplexer / demultiplexer is connected to a Fabry-Perot laser diode, a common terminal of the multiplexer / demultiplexer is connected to a second terminal of the optical circulator, and a first terminal of the optical circulator is the non-interference A wavelength-division-multiplexed optical system, wherein the optical circulator has a third terminal connected to an input terminal of the external modulator, and the external modulator is connected to the external modulator driver. Transmission equipment.   The optical receiver further includes an optical receiver connected to an input terminal of the external modulator driving device, and the optical receiver converts the input optical signal into an electrical signal, and then converts the optical signal into an optical signal and outputs the signal again. The wavelength division multiplexing optical transmission apparatus according to claim 17.   The wavelength division multiplexing optical transmission apparatus according to claim 17, further comprising a multiplexer / demultiplexer temperature control device for controlling a temperature of the multiplexer / demultiplexer.   The wavelength division multiplexing optical transmission apparatus according to claim 17, further comprising N polarization controllers connected between a terminal of the multiplexer / demultiplexer and the Fabry-Perot laser diode.   The wavelength division multiplexing optical transmission apparatus according to claim 17, further comprising a polarization controller connected between a third terminal of the optical circulator and the external modulator.   The wavelength division multiplexing optical transmission device according to claim 17, further comprising a laser diode temperature control device for controlling a temperature of the Fabry-Perot laser diode.

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