CN203084362U - Delay adjustable device based on active fiber grating coupler - Google Patents

Abstract

The utility model discloses a delay adjustable device based on an active fiber grating coupler. The delay adjustable device comprises an adjustable light source, an optical circulator, a pump light source, a wave length division multiplexer, the fiber grating coupler mixed with a single fiber core, a first receiver and a second receiver. Signals output by the adjustable light source enter from a first port of the optical circulator through connection of optical fiber and are output from a second port of the optical circulator. Output signal light and the pump light source are coupled into one piece of optical fiber through the wave length division multiplexer and connected to a first port of the fiber grating coupler mixed with the single fiber core, and generate reflected light at the first port and a second port of the fiber grating coupler mixed with the single fiber core. The reflected light generated at the first port is output through the first port, enters from the second port of the optical circulator after de-multiplexing through the wave length division multiplexer, is output through a third port of the optical circulator, and enters the first receiver. The reflected light generated at the second port of the fiber grating coupler mixed with the single fiber core can be directly input into the second receiver.

Description

Based on the adjustable device of the time delay of Active Optical Fiber grating coupler

Technical field

The utility model belongs to the optical information technical field, is specifically related to the adjustable device of a kind of time delay based on the Active Optical Fiber grating coupler, perhaps is referred to as the adjustable slower rays delayer based on the Active Optical Fiber grating coupler.

Background technology

In modern optical fiber telecommunications system, the increase of network information transfer capacity is had higher requirement to the processing power of communication network intermediate node, and existing the problem that photoelectricity light is changed in the middle of traditional optical-fiber network, this has limited the further increase of network transmission capacity.The complete photochemical solution for this problem of network provides scheme, and the complete photochemical basis of network is full optical routing, because the processing power of intermediate node has directly influenced the transmission speed of whole network.Traditional route be circuit by, but,, can not finish Signal Processing even intermediate node can satisfy the opto-electronic conversion of the signal of arbitrary velocity for the light signal of high-speed transfer.In full optical routing, paired pulses optionally postpones, and can avoid collisions of pulses.Therefore, the time delay of light is adjustable has important use and is worth.

The time delay adjustability of light has important use in optical communication network, as light buffer memory, packet synchronization and shake control, light signal processing etc.The speed of pulse even may reduce to zero under the specified conditions, the information of carrying in pulse this moment can be transferred in the medium, forms optical storage.The group velocity of light pulse depends on the dispersion characteristics of media, therefore can come the group velocity of gating pulse by the dispersion parameters of regulating grating, produces slower rays and time delay.In the ordinary passive fiber grating, different off resonance amounts can produce different time delays, but the flashlight frequency of transmitting in the optical fiber is certain, and the difficulty of carrying out wavelength Conversion is bigger, and infeasible.And the time delay of paired pulses is limited in the ordinary passive grating, can not satisfy the demand of signal Processing sometimes.In one or two fibre core of fibre optic grating coupler, just obtain the Active Optical Fiber grating coupler behind the doped with rare-earth elements.In this device, by the variation of pumping light power being realized control, and then reach the adjustable purpose of time delay to group delay.

Fibre optic grating coupler combines the characteristics of good wavelength selective power of fiber grating and fiber coupler multiport, be convenient to add drop multiplex, the time delay of its generation has important use in light signal processing, optical storage, full optical routing, add after the gain can also abatement device Power Limitation.

Based on the adjustable slower rays delayer of Active Optical Fiber grating coupler, can reach the purpose that time delay is controlled by change, and the adjustable delay time bigger than passive optical fiber grating can be provided gain coefficient.And the problem that existing adjustable slower rays delayer technology exists is: the time delay that fiber grating produces is little, adjustability is low.

The utility model content

Shortcomings such as the time delay that produces at the existing fiber grating is little, adjustability is low the utility model proposes the adjustable device of a kind of time delay based on the Active Optical Fiber grating coupler.

The utility model is taked following technical scheme: based on the adjustable device of the time delay of Active Optical Fiber grating coupler, comprise tunable light source (1), optical circulator (2), pump light source (3), wavelength division multiplexer (4), the fibre optic grating coupler (5) that single core is mixed, first receiver (6-1) and second receiver (6-2), the connection of the signal of tunable light source (1) output by optical fiber enters from first port (2-1) of optical circulator (2), export from second port (2-2) of optical circulator (2) then, the flashlight and the pump light source (3) of output are coupled in the optical fiber by wavelength division multiplexer (4), and be connected to first port (5-1) of the fibre optic grating coupler (5) that single core mixes, first port (5-1) and second port (5-2) of the fibre optic grating coupler (5) that mixes in single core locate to produce reflected light, export by first port (5-1) at the reflected light that first port (5-1) produces, behind wavelength division multiplexer (4) demultiplexing, second port (2-2) by optical circulator (2) enters optical circulator again, export from the 3rd port (2-3) of optical circulator then, and enter first receiver (6-1); The reflected light that second port (5-2) of the fibre optic grating coupler (5) that mixes in single core produces directly inserts second receiver (6-2).The flashlight that obtains on receiver (6-1) and receiver (6-2) is compared the delay that has in various degree with the output light in the tunable light source (1), and can be along with the difference of pump light source (3) power input difference.

Preferably, the wavelengthtunable scope of tunable light source (1) is 1530nm to 1570nm.

Preferably, the operation wavelength of pump light source (3) is 980nm.

Preferably, the operation wavelength of wavelength division multiplexer (4) is 980nm/1550nm.

Preferably, the working range of fibre optic grating coupler (5) is 1530nm to 1570nm.

In the technical solutions of the utility model, adopt the reflected signal that optical circulator produces fiber grating and the Signal Spacing of forward transmitted to come, this mode can be close or identical to frequency preferably but light that the direction of propagation is different isolate.The active device that adopts is the rear-earth-doped fibre optic grating coupler of single fibre core, and the mode that adds pumping by the outside realizes.And utilize the fiber grating filtering characteristic that the flashlight of different frequency is optionally reflected.For the fixing fiber grating of Bragg frequency, select the signal of different frequency can produce different time delays, add the time delay that gain also can change signal.

The signal wave of input is from 1 port incident of optical circulator, after the output of 2 ports through a wavelength division multiplexer and the pump light laggard optical fiber grating coupler of going into that is coupled.The light that the process fibre optic grating coupler is handled is exported at 3 ports from 2 port incidents of optical circulator.

The utility model foundation theoretical as follows:

The first step: determine reflection coefficient.

The grating reflection coefficient is the ratio of grating port reflected light and incident light, comprises amplitude and phase place.Reflection coefficient has characterized the filtering characteristic of grating.

Second step: the phase place of determining reflection coefficient.

If r turns to reflection coefficient θ then _rPhase place for reflection coefficient.The time delay of grating is expressed as:

$\mathrm{\ι}=\frac{d{\mathrm{\θ}}_r}{\mathrm{d\ω}}=-\frac{{\mathrm{\λ}}^2}{2\mathrm{\πc}}\frac{d{\mathrm{\θ}}_r}{\mathrm{d\λ}}---\left(1\right)$

In the Active Optical Fiber grating coupler, the affiliation that adds of gain changes reflection coefficient r, and then changes θ _r, influence the time delay of device.

The utility model adopts the fibre optic grating coupler of single fibre core doping as gain media, and the grating in the fibre optic grating coupler is realized the feedback output of signal as wave filter.Compare existing fiber grating and fibre optic grating coupler, gain can change the distribution of time delay peak value, make and bigger time delay peak value away from stopband the time, also can occur, and the time delay at identical off resonance amount place is changed with the difference that gains, so can reach the adjustable purpose of time delay by control to gain.The time delay that this method obtains is tunable, and this makes bigger in the potentiality of photon microwave regime based on the adjustable slower rays delay device of Active Optical Fiber grating coupler, applicatory wider general.

The utility model is adjustable slower rays delay device simple in structure, cost is low, be easy to add drop multiplex, time delay is tunable, it is specially adapted to technical fields such as optical communication, light signal processing, light buffer memory.

Description of drawings

Fig. 1 is the structural representation of the utility model based on the adjustable device of time delay of Active Optical Fiber grating coupler.

Fig. 2 is that gain is that 0 o'clock time delay is with off resonance quantitative change curve.

Embodiment

Below in conjunction with accompanying drawing the utility model embodiment is elaborated.

As shown in Figure 1, embodiment comprises fibre optic grating coupler 5, the receiver 6 that tunable light source 1, optical circulator 2,980nm pump light source 3,980nm/1550nm wavelength division multiplexer 4, single core are mixed based on the adjustable device of the time delay of Active Optical Fiber grating coupler, receiver has two, i.e. the first receiver 6-1 and the second receiver 6-2.Present embodiment only illustrates the situation of flashlight from a port incident of fibre optic grating coupler.

Tunable light source 1 connects the port 2-1 of optical circulator 2 by optical fiber, the connection of the signal of tunable light source 1 output by optical fiber enters optical circulator 2 from the port 2-1 of optical circulator 2, (port 2-2 connects wavelength division multiplexer 4 by optical fiber from the port 2-2 of optical circulator 2 output then, wavelength division multiplexer 4 also links to each other with pump light source 3 by optical fiber), the flashlight and the 980nm pump light source 3 of port 2-2 output are coupled in the optical fiber by wavelength division multiplexer 4, this optical fiber is connected to the fibre optic grating coupler 5 that single core is mixed, and then produces reflected light at its port 5-1 and port 5-2 place.The reflected light that produces in port 5-1 is by port 5-1 output, enter optical circulator through the port 2-2 by optical circulator 2 behind wavelength division multiplexer 4 demultiplexings, from the port 2-3 output of optical circulator, enter receiver 6-1(port 2-3 and link to each other with receiver 6-1 then) by optical fiber.The direct input receiver 6-2(of the reflected light that produces in port 5-2 port 5-2 links to each other with receiver 6-2 by optical fiber).

Open tunable light source 1, regulate tunable light source 1 frequency, obtain in the ordinary optic fibre grating coupler different frequency place time delay with the variation relation of off resonance amount, as shown in Figure 2.Open pump light source 3, and the fixing output power of pump light source, regulate tunable light source 1 frequency, obtain in the Active Optical Fiber grating coupler different frequency place time delay with the variation relation of off resonance amount.The frequency of stationary adjustable light source 1 is regulated the power of pump light source 3, obtains in the Active Optical Fiber grating coupler fixedly off resonance amount place time delay with the variation relation of gain.

The utility model postpones the process of output based on the adjustable slower rays of Active Optical Fiber grating coupler:

1,, select suitable pumping wave, signal wave wavelength to satisfy the condition that produces required time delay according to required optical pulse frequency.

2, select operating wavelength range to cover optical circulator and fibre optic grating coupler that signal post needs the output wavelength scope of laser instrument.

3,, select the fibre optic grating coupler of suitable reflection wavelength according to the wavelength coverage of communication desired signal.

4, open tunable light source and pump light source, regulate tunable light source and pump light source output power, regulate the output wavelength of tunable light source, the adjustable delay time device is realized stable signal time delay.The time delay of signal changes thereupon behind the change pumping light power.

The utility model reaches the adjustable purpose of time delay by the control to gain.Continuous development along with various photoelectric devices will obtain more stable output, and its application will be more extensive also.

More than preferred embodiment of the present utility model and principle are had been described in detail; for those of ordinary skill in the art; according to the thought that the utility model provides, the part that on embodiment, can change, and these changes also should be considered as protection domain of the present utility model.

Claims (5)

1. based on the adjustable device of the time delay of Active Optical Fiber grating coupler, it is characterized in that: comprise tunable light source (1), optical circulator (2), pump light source (3), wavelength division multiplexer (4), the fibre optic grating coupler (5) that single core is mixed, first receiver (6-1) and second receiver (6-2), the connection of the signal of tunable light source (1) output by optical fiber enters from first port (2-1) of optical circulator (2), export from second port (2-2) of optical circulator (2) then, the flashlight and the pump light source (3) of output are coupled in the optical fiber by wavelength division multiplexer (4), and be connected to first port (5-1) of the fibre optic grating coupler (5) that single core mixes, first port (5-1) and second port (5-2) of the fibre optic grating coupler (5) that mixes in single core locate to produce reflected light, export by first port (5-1) at the reflected light that first port (5-1) produces, behind wavelength division multiplexer (4) demultiplexing, second port (2-2) by optical circulator (2) enters optical circulator again, export from the 3rd port (2-3) of optical circulator then, and enter first receiver (6-1); The reflected light that second port (5-2) of the fibre optic grating coupler (5) that mixes in single core produces is directly imported second receiver (6-2).

2. the adjustable device of the time delay based on the Active Optical Fiber grating coupler as claimed in claim 1 is characterized in that: the wavelengthtunable scope of described tunable light source (1) is 1530nm to 1570nm.

3. the adjustable device of the time delay based on the Active Optical Fiber grating coupler as claimed in claim 1 is characterized in that: the operation wavelength of described pump light source (3) is 980nm.

4. the adjustable device of the time delay based on the Active Optical Fiber grating coupler as claimed in claim 1 is characterized in that: the operation wavelength of described wavelength division multiplexer (4) is 980nm/1550nm.

5. as the adjustable device of each described time delay based on the Active Optical Fiber grating coupler of claim 1-4, it is characterized in that: the working range of described fibre optic grating coupler (5) is 1530nm to 1570nm.

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