CN102243413A - Composite type double-channel continuous adjustable light delay - Google Patents

Abstract

The invention relates to a continuous adjustable light delay, in particular to a composite type double-channel continuous adjustable light delay, and solves the problem that the conventional light delay cannot have delay quantity and adjustable continuity simultaneously and can realize the ten-micro-second adjustable delay of a double-channel signal. A slowdown (to-be-delayed) signal, namely signal 1, in the double-channel signal enters a Brillouin optical fiber ring which consists of a first switch, an optical isolator, a polarization controller, a first optical fiber, a circulator and an attenuator and is subjected to Brillouin slowdown light delay and linear light transmission delay in the Brillouin optical fiber ring; the signal in the other channel, namely signal 2, enters a second optical fiber ring which consists of a second switch and a second optical fiber and is subjected to the linear light transmission delay in the second optical fiber ring; a delay quantity difference between the signal 1 and the signal 2 is relative delay of the two signals; and adjustment of the light delay is realized by controlling a time sequence of the first control switch and the second control switch and using the power of a pump light. The composite type double-channel continuous adjustable light delay is applicable to light cache, light storage, data synchronization and light signal processing.

Description

The continuous tunable optical chronotron of compound binary channels

Technical field

The present invention relates to a kind of continuous tunable optical chronotron.

Background technology

The controllable light chronotron has important application prospects at aspects such as light buffer memory, optical storage, data sync and light signal processing, is one of vitals of realizing full ray laser communication.Continuously whether adjustable and reference time delay is big or small is two important parameters weighing the optical time delay unit performance.Present optical time delay unit can't be taken into account this two aspects: the general adjustable delay scope of chronotron that promptly possesses the time-delay adjustable function is little, and the chronotron that the adjustable delay scope is big generally can not be realized continuously adjustable.

Summary of the invention

The present invention can't take into account amount of delay and adjustable successional problem in order to solve existing optical time delay unit, thereby provides a kind of compound binary channels continuous tunable optical chronotron.

The continuous tunable optical chronotron of compound binary channels, it comprises the Brillouin fiber optic ring and second fiber optic loop, described Brillouin fiber optic ring is made up of gauge tap, optoisolator, Polarization Controller, optical fiber, circulator and an attenuator; Second fiber optic loop is made up of No. two gauge tap and No. two optical fiber; The length of an optical fiber is 2 times of No. two optical fiber;

Treat that inhibit signal inputs to optoisolator through an output terminal of a gauge tap, after handling, optoisolator inputs to Polarization Controller, after handling, injects Polarization Controller an optical fiber, pump light injects an optical fiber by circulator, described pump light interacts with treating inhibit signal in an optical fiber, generation is based on the slower rays time-delay of Brillouin scattering effect, signal after the time-delay inputs to attenuator through circulator, after attenuator is handled, input to an input end of a gauge tap, finish once going in ring in the Brillouin fiber optic ring; Carry out repeatedly going in ring for N1 time after the inhibit signal output terminal for the treatment of of a gauge tap is exported;

The second road signal injects No. two optical fiber through an output terminal of No. two gauge tap, inputs to an input end of No. two gauge tap after these No. two Optical Fiber Transmission, finishes once going in ring in second fiber optic loop; Carry out repeatedly going in ring for N2 time after the second road signal output part output of No. two gauge tap;

N1 and N2 are positive integer.

In the Brillouin fiber optic ring, treat that inhibit signal carries out going in ring for N1 time repeatedly after, total light time-delay is Δ t, the maximum of T max of light time-delay is by the circulation number of turns and the common decision of each circle gain, wherein each circle gains and is regulated by pump power.

Treat that inhibit signal with respect to the time-delay of the second road signal is:

${\mathrm{\&Delta;T}}_d=(N_1-{\mathrm{<figure-callout\; id="2"\; label="N"\; filenames="HDA0000074645670000011.png,HDA0000074645670000012.png"\; state="\{\{state\}\}">N</figure-callout>}}_2\frac{1}{2})\mathrm{\&Delta;T}+\mathrm{\&Delta;t}$

Δ T is the individual pen transit time that is caused by transmission in the Brillouin fiber optic ring in the formula, and the individual pen transit time in second fiber optic loop is Δ T/2.

The present invention has taken into account the reference time delay of continuous tunable optical amount of delay, and the adjustable delay scope has realized continuous adjustable in the time of big; Can realize the continuous controllable light time-delay of nanosecond to the microsecond level.

Description of drawings

Fig. 1 is a structural representation of the present invention, mark 11 be a gauge tap treat the inhibit signal input end; Mark 71 is the second road signal input part of No. two gauge tap; Fig. 2 is the synoptic diagram of amount of delay described in the embodiment.

Embodiment

Embodiment one, present embodiment is described in conjunction with Fig. 1, the continuous tunable optical chronotron of compound binary channels, it comprises the Brillouin fiber optic ring and second fiber optic loop, and described Brillouin fiber optic ring is made up of gauge tap 1, optoisolator 2, Polarization Controller 3, optical fiber 4, circulator 5 and an attenuator 6; Second fiber optic loop is made up of No. two gauge tap 7 and No. two optical fiber 8; The length of an optical fiber 4 is 2 times of No. two optical fiber 8;

Treat that inhibit signal (signal 1) inputs to optoisolator 2 through an output terminal 13 of a gauge tap 1, after handling, optoisolator 2 inputs to Polarization Controller 3, after handling, Polarization Controller 3 injects an optical fiber 4, pump light injects an optical fiber 4 by circulator, described pump light interacts with treating inhibit signal in an optical fiber 4, generation is based on the slower rays time-delay of Brillouin scattering effect, signal after the time-delay inputs to attenuator 6 through circulator, after attenuator 6 is handled, input to an input end 14 of a gauge tap 1, finish once going in ring in the Brillouin fiber optic ring; Carry out repeatedly going in ring for N1 time after the inhibit signal output terminal 12 for the treatment of of a gauge tap 1 is exported;

The second road signal (signal 2) injects No. two optical fiber 8 through an output terminal 73 of No. two gauge tap 7, inputs to an input end 74 of No. two gauge tap 7 after these No. two optical fiber 8 transmission, finishes once going in ring in second fiber optic loop; Carry out repeatedly going in ring for N2 time after the second road signal output part, 72 outputs of No. two gauge tap 2;

Described N1 and N2 are positive integer.

The difference of embodiment two, this embodiment and the continuous tunable optical chronotron of embodiment one described compound binary channels is, in the Brillouin fiber optic ring, after treating that inhibit signal carries out going in ring for N1 time repeatedly, total light time-delay is Δ t, the maximum of T max of light time-delay is determined jointly by the circulation number of turns and each circle brillouin gain, wherein respectively encloses brillouin gain and regulated by pump power.

The difference of embodiment three, this embodiment and the continuous tunable optical chronotron of embodiment one described compound binary channels is, treats that inhibit signal with respect to the time-delay of the second road signal is:

${\mathrm{\&Delta;T}}_d=(N_1-{\mathrm{<figure-callout\; id="2"\; label="N"\; filenames="HDA0000074645670000011.png,HDA0000074645670000012.png"\; state="\{\{state\}\}">N</figure-callout>}}_2\frac{1}{2})\mathrm{\&Delta;T}+\mathrm{\&Delta;t}$

Δ T is the individual pen transit time that is caused by transmission in the Brillouin fiber optic ring in the formula, and the individual pen transit time in second fiber optic loop is Δ T/2.

Principle of work: Brillouin's enlarge-effect possesses the light speed reduction effect, and the group velocity of the flashlight that promptly has been exaggerated can descend, and its slower rays amount of delay can be regulated by the pumping light power of brillouin effect and realize.By regulating pumping light power, can the conditioning signal gain of light, thus the light modulation amount of delay.Because it is Continuous Mappings that the mapping light from pumping light power to the slower rays amount of delay prolongs, and pumping light power can be regulated continuously, so Brillouin's slower rays amount of delay also can be regulated continuously.

The present invention is based on the compound slower rays chronotron that annular Brillouin amplifies time-delay structure, it can obtain nanosecond to the time-delay of the continuously adjustable slower rays of microsecond level, and the present invention makes and treats that the inhibit signal experience amplified the slower rays time-delay that causes and getted over time-delay by what transmission caused by Brillouin.The second road signal only experiences by transmit the time-delay of getting over that causes in No. two optical fiber 8.Treat that the inhibit signal and the second road signal round-robin number of times in ring separately controlled respectively by the switch from each, the individual pen transit time that is caused by transmission in the Brillouin fiber optic ring is Δ T, and then the individual pen transit time in second fiber optic loop is Δ T/2.Be located in the Brillouin fiber optic ring, the total slower rays time-delay introduced behind the N1 circle that circulated that is caused by Brillouin's enlarge-effect is Δ t, and its maximal value is Tmax, and Tmax is by the circulation number of turns and each circle gain decision jointly, and wherein each circle gain can be regulated by pump power.After this system, signal 1 with respect to the time-delay of signal 2 is:

${\mathrm{\&Delta;T}}_d=(N_1-{\mathrm{<figure-callout\; id="2"\; label="N"\; filenames="HDA0000074645670000011.png,HDA0000074645670000012.png"\; state="\{\{state\}\}">N</figure-callout>}}_2\frac{1}{2})\mathrm{\&Delta;T}+\mathrm{\&Delta;t}$

Wherein:

N ₂＝0，1，2…2N1

Δt＝[0，T _max]

Treat inhibit signal at middle round-robin number of times except that being subjected to the control of gauge tap, also be decided by brillouin gain and ring internal loss that it bore.In real work, for the guarantor levies the SBS that does not produce self-excitation in the ring, brillouin gain is less than the ring internal loss.This makes treats state ring in the circulation of inhibit signal with decay.By regulating the pumping light power in the Brillouin fiber optic ring, corresponding change loop loss, the difference of the two remained unchanged by regulating variable attenuator, can the situation that the global cycle number of times is constant in keeping loop under, realization is regulated between [0, Tmax] continuously to Δ t.For given Δ t, amount of delay Δ T _dCan obtain following value, as shown in Figure 2, that is: 0+ Δ t, Δ T/2+ Δ t, Δ T+ Δ t...N ₁Δ T+ Δ t

As seen, if T _Max〉=Δ T/2 is because Δ t is adjustable continuously.By regulating gauge tap control control N No. two ₂Value, just can make Δ T _dValue can be 0 to N ₁Change continuously between the Δ T+ Δ t.

Embodiment four, present embodiment adopt the structure of embodiment three, flashlight 31 circles that in the Brillouin fiber optic ring, gone in ring, wherein:

No pumping transit time Δ T is:

ΔT＝572ns

Slower rays time-delay based on stimulated Brillouin scattering is:

Δt＝468ns

Realized Δ t 〉=Δ T/2, so T _Max〉=Δ T/2.

Total amount of delay is:

N ₁ΔT+Δt＝31×572+468≈18μs

Obtained the continuous adjustable delay of 0 to 18 microsecond.Resolution is regulated in its time-delay can reach nanosecond.

For any given delay time Δ T _d, its amount of delay is made up of two parts, and a part is linear amount of delay, and another part is the amount of delay Δ t that is introduced by the stimulated Brillouin scattering slow light effect.For given Δ T _d, the combination of a variety of N1 and N2 is arranged.Choose try one's best few N1 and N2, help obtaining high signal to noise ratio (S/N ratio), and system has less inherent delay.Choosing method is:

${\mathrm{<figure-callout\; id="1"\; label="N"\; filenames="HDA0000074645670000011.png"\; state="\{\{state\}\}">N</figure-callout>}}_1=\max (\mathrm{ceil}\left(\frac{1}{2}\right[\frac{{2\mathrm{\&Delta;T}}_d}{\mathrm{\&Delta;T}}\left]\right),M)$

${\mathrm{<figure-callout\; id="2"\; label="N"\; filenames="HDA0000074645670000011.png,HDA0000074645670000012.png"\; state="\{\{state\}\}">N</figure-callout>}}_2={2N}_1-\left[\frac{{2\mathrm{\&Delta;T}}_d}{\mathrm{\&Delta;T}}\right]$

Wherein, ceil[x] for getting smallest positive integral, [x] integral part for getting x more than or equal to x.M records related data according to concrete Brillouin's slower rays time delay ring and determines.Specific as follows, pump light is adjusted to Brillouin's maximal value during no self-excitation SBS generation in encircling, the flashlight annular number of turns maximum that this moment, Brillouin encircled, during as 31 circles, the slower rays amount of delay that causes by stimulated Brillouin scattering of each circle of record, maximum slower rays amount of delay that the amount of delay of this moment obtains for each circle is accumulated since the slower rays amount of delay of the 1st circle, until minimum number of turns M, make from the 1st and enclose the accumulation slower rays amount of delay of M circle more than or equal to given Δ T _dIn Brillouin's amount of delay Δ t:

$\mathrm{\&Delta;t}={\mathrm{\&Delta;T}}_d-\left[\frac{{2\mathrm{\&Delta;T}}_d}{\mathrm{\&Delta;T}}\right]\frac{\mathrm{\&Delta;<figure-callout\; id="2"\; label="T"\; filenames="HDA0000074645670000011.png,HDA0000074645670000012.png"\; state="\{\{state\}\}">T</figure-callout>}}{2}$

The M value is desirable fixed.This value has characterized flashlight experience M circle just can reach corresponding Brillouin's amount of delay.

The N1 and the N2 that determine have just determined linear amount of delay.By falling pump light, Δ t can be adjusted to and treat regulated value, thereby realize whole Δ T _dAmount of delay.

Claims (3)

1. the continuous tunable optical chronotron of compound binary channels, it is characterized in that: it comprises the Brillouin fiber optic ring and second fiber optic loop, and described Brillouin fiber optic ring is made up of a gauge tap (1), optoisolator (2), Polarization Controller (3), an optical fiber (4), circulator (5) and attenuator (6); Second fiber optic loop is made up of No. two gauge tap (7) and No. two optical fiber (8); The length of an optical fiber (4) is 2 times of No. two optical fiber (8);

Treat that inhibit signal inputs to optoisolator (2) through an output terminal (13) of a gauge tap (1), after handling, optoisolator (2) inputs to Polarization Controller (3), after handling, injects Polarization Controller (3) optical fiber (4), pump light injects an optical fiber (4) by circulator (5), described pump light interacts with treating inhibit signal in an optical fiber (4), generation is based on the slower rays time-delay of Brillouin scattering effect, signal after the time-delay inputs to attenuator (6) through circulator (5), after attenuator (6) is handled, input to an input end (14) of a gauge tap (1), finish once going in ring in the Brillouin fiber optic ring; Carry out repeatedly going in ring for N1 time after the inhibit signal output terminal (12) for the treatment of of a gauge tap (1) is exported;

The second road signal injects No. two optical fiber (8) through an output terminal (73) of No. two gauge tap (7), inputs to an input end (74) of No. two gauge tap (7) after this No. two optical fiber (8) transmission, finishes once going in ring in second fiber optic loop; Carry out repeatedly going in ring for N2 time after the second road signal output part (72) output of No. two gauge tap (2);

Described N1 and N2 are positive integer.

2. the continuous tunable optical chronotron of compound binary channels according to claim 1, it is characterized in that in the Brillouin fiber optic ring, after treating that inhibit signal carries out going in ring for N1 time repeatedly, total light time-delay is Δ t, the maximum of T max of light time-delay is determined jointly by the circulation number of turns and each circle brillouin gain, wherein respectively encloses brillouin gain and regulated by pump power.

3. the continuous tunable optical chronotron of compound binary channels according to claim 1 is characterized in that treating that inhibit signal with respect to the time-delay of the second road signal is:

${\mathrm{\&Delta;T}}_d=(N_1-N_2\frac{1}{2})\mathrm{\&Delta;T}+\mathrm{\&Delta;t}$

Δ T is the individual pen transit time that is caused by transmission in the Brillouin fiber optic ring in the formula, and the individual pen transit time in second fiber optic loop is Δ T/2.

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