Multichannel optical input/output multiplexer with dynamic functionality

FIELD: information technologies.

SUBSTANCE: device for fiber-optic communication system with wavelength-division multiplexing 2N channels where N is integer and N≥2 with spectral interval between adjacent channels Δv0 for performing input/output of 2M channels where M is integer and 1≤M<N, has one entering port, one exiting port, 2M output ports, 2M input ports and contains: controlled optical input/output multiplexer, optical demultiplexer of "1×2M" configuration, optical multiplexer of "2M×1" configuration and controller. This device can be used as multichannel controlled or multichannel reconfigurable optical input/output multiplexer.

EFFECT: performing input and output of multiple channels from optical signal with channel wavelength-division multiplexing using controlled dynamic filtering elements capacity restructuring.

13 cl, 16 dwg, 3 tbl

 

The invention relates to fiber-optic communication systems with wavelength division multiplexing channels, in particular to multi-configurable and controllable optical multiplexers I/o channels (hereinafter t-OADM and ROADM) and can be used in systems dense spectral multiplexing (DWDM), and moderate spectral multiplexing (CWDM).

New technology in fiber optic communication systems using spectral seal, become dominant in modern communication systems. Dense wavelength seal, DWDM, used in long-haul communication lines, moderate spectral seal, CWDM, is used in urban and local communication systems.

The DWDM technology is characterized by extremely high bandwidth, but are very expensive. Standard on-grid wavelengths, entered the International Telecommunication Committee (hereinafter ITU-Standard)provides the spectral interval between channels 200, 100, 50 or 25 GHz. Recommended by ITU-Standard spectral interval between channels CWDM systems is 20 nm. Technique CWDM easier to use and cheaper than DWDM.

At the nodal points VOSS for I/o channels are used for optical multiplexers I / o (hereinafter OADM). They allow the line one or more channel is in and at the same time to enter the signal on the same wavelength with the new information and the efficiency of communication systems increases. The number of channels of input/output is usually substantially less than the total number of channels in the line.

Multi-channel OADM, as a rule, fixed frequency channels input/output. Systematically increasing bandwidth requirements of communications systems require greater flexibility, in particular, the use of reconfigurable and managed multi-channel OADM. These devices, except for use in optical communication networks, may have other applications, for example, in multi-channel systems, sensors, optical filtering in analog systems for various purposes.

Known to the present time reconfigurable OADM (hereinafter ROADM) have a number of disadvantages, the main of which is that these devices are rather complicated and expensive, and managed OADM (hereinafter t-OADM) allow you to enter/display only one channel. Note that the authors of the present invention, mention multi-channel ROADM and t-OADM, mean device, in which for each output and the newly input channel has an individual port.

Well-known specialists in the field of optical communication systems approach to the task of creating a ROADM is to use pair - demultiplexer configuration "1×" and the multiplexer configuration "×1", the output and the input which are connected and form To the pistes ( the total number of channels in the system). In each of the tracks has optical Electromechanical switch (hereinafter MEMS). The specified optical demultiplexer splits the optical signal To channels and sends each channel to one of the tracks To. MEMS miss some of the channels to the optical multiplexer, and the other part of the channels is directed into the output ports. The specified optical multiplexer combines all channels, including the newly introduced using the same MEMS, and returns them in the optical line. Obviously, being implemented using this approach, the device would have a high cost, the greater, the greater would be the number of channels To and less than the spectral interval between adjacent channels.

Another approach (US, 6602000, B2) is to use two pairs of the demultiplexer and the multiplexer, but simpler configurations 1×L and L×1, where L=K/R, K is the total number of channels and P is an integer. The inputs and outputs of the demultiplexer and multiplexer are again connected and form the L tracks, each track has multiple, number R, multiplexers I / o OADM, each made on the basis of the asymmetric interferometer of Mach-Zehnder interferometers (the EMC) with built-in arms of the interferometer Brekhovskikh diffraction gratings. When the control temperature the influence of the period of the diffraction grating m is may to some extent be changed to be equal to or not equal to the wavelength of one of the channels, and, consequently, with such OADM can be done or not to be I/o channel with the corresponding wavelength.

Upon receipt of the input of the device in question signal, including To the channel spacing between adjacent channels Δν, the channels are separated by the optical demultiplexer for L subsets, each subset - R channel spacing between channels L·Δν. With the passage of the signal on one of lines with chain OADM can be withdrawn any specified channels. All the other channels with the newly introduced channels at frequencies derived channels are combined by an optical multiplexer and transmitted to the optical line.

It is clear that in the case of a large number of channels in the optical system, this device would also be very difficult to manufacture and expensive. With this structure, containing a large number of MTS, each of which has its breggovskie individual diffraction gratings in the two shoulders and thermal control system, would be cumbersome and unreliable.

Thus, at the present time there is no multi-channel reconfigurable and managed OADM, which really would be suitable for use in optical communication lines and would be easy to manufacture, reliable in operation and would be acceptable with aImost.

The aim of the present invention is to provide a multi-channel OADM with dynamic behavior, which in various embodiments can be used as multi-channel ROADM or as a multi-t-OADM. The device should be more simple in design than the known approaches to meet the existing requirements for isolation channels and make dispersion and be suitable for integrated optical implementation. If possible, the device should be as dynamic and flexible for use in different WDM systems.

While the invention has been set the task of developing devices for input/output channels of the optical signal with wavelength division multiplexing channels using a managed dynamic adjustment of the bandwidth of the filter elements.

The task was solved by the creation of a multi-managed optical multiplexer input/output with dynamic functionality for fiber-optic communication systems with wavelength division multiplexing 2Nchannels when N is an integer and N≥2 for the spectral interval between adjacent channels Δν0for I/o 2Mchannels when M is an integer with 1≤M<N, having one input port, one output port, 2Moutput ports, 2M ports input and including:

- managed optical multiplexer input/output providing the output of the 2Mchannels into a single output port and the input of new 2Mchannels on carrier frequencies derived channels into a single output port;

- optical demultiplexer configuration 1×2M"connected to its input port with the output port of the specified managed optical multiplexer input/output

optical multiplexer configuration "2M×1", connected to its output port with the input port of the specified managed optical multiplexer input/output

- controller.

Thus, according to the invention, it is expedient that the specified managed optical multiplexer input/output was:

- (N-M)-stage structure, containing in each stage one optical filter having one input and two outputs, made with the possibility of a managed realignment transmission ratios, characterized in n1tier-n1=1,2,...,(N-M) frequency interval between adjacent extrema in the dependency ratios of the transmission frequency Δνn1=2n1-1Δν1;

- optical adder having N-M+1 inputs and one output connected to the output port.

In addition, according to the invention, it is advisable that specified in (N-M)-stage structure:

op is practical filter of each stage, except for the last stage, one of the outputs was connected to the input of the optical filter in the subsequent stage, and the output was connected to one of inputs of the optical adder;

- optical filter of the first stage of their input was connected to the input port;

- optical filter of the last stage one output was connected to another one of the input optical adder, and the output was connected to the output port;

- optical adder other input was connected to the input port.

the optical output of the adder was connected to the output port.

Thus, according to the invention, it is expedient to provide multi-channel multiplexer has been adapted to control the I/o channels in a reconfigurable manner, in the optical demultiplexer and the multiplexer had fixed spectral characteristics and the controller is electrically connected with the specified controllable optical multiplexer input/output.

In addition, according to the invention, it is expedient to provide multi-channel multiplexer has been adapted to control the I/o channel in the VFO mode, the optical demultiplexer and the multiplexer was tunable spectral characteristics and the controller is electrically connected to the specified managed optical is Kim multiplexer I/o, the optical demultiplexer and the multiplexer.

Thus, according to the invention, in a multi-channel multiplexer, adapted to control the I/o channel in the VFO mode, the specified optical demultiplexer included M-stage structure of type "tree"containing each n2tier-n2=1,2,...,M2n2-1optical filters having at least one input and two outputs, made with the possibility of a managed realignment transmission ratios, characterized in n2tier-frequency interval between adjacent extrema in the dependency ratios of the transmission frequency equal to

Δνn2=2n2+N-M-1Δν1.

Thus, according to the invention, it is expedient that the optical demultiplexer in the specified M-step the structure of one of the inputs of the optical filter of the first stage was connected with the input port, each of the two outputs of the optical filter of the last stage was connected with one of the output ports and the optical filters in each stage, except the last, were connected to each of two outputs to the input of one of the optical filters next level.

In addition, according to the invention, it is expedient that the specified optical multiplexer included M-stage structure of type "tree", with the each containing a series of n 3tier-n3=1,2,...,M is not less than 2M-n3optical filters having two inputs and at least one output made with the possibility of a managed realignment transmission ratios, characterized in n3tier-frequency interval between adjacent extrema in the dependency ratios of the transmission frequency Δνn3=2N-n3·Δν1.

Thus, according to the invention, it is expedient that the optical multiplexer in the specified M-step the structure of the two input optical filters of the first stage were connected with the input ports, one output of the optical filter of the last stage was connected with the output port and the optical filters in each stage, except the first and last, were connected to each of the two inputs with the output of one of the optical filters of the previous stage, and one output to one of the inputs of one of the optical filters next level.

Thus, according to the invention, it is advisable that the quality of these optical filters were used for single-stage and/or two-stage and/or multi-stage unbalanced interferometers, Mach-Zehnder interferometers.

In addition, according to the invention, it is expedient, in order to control the setting of the transfer coefficients of the specified optical filters contained electro-optical or imootence device phase shift.

Thus, according to the invention, it is expedient to provide multi-channel multiplexer was performed on the integrated optical technologies on a single chip.

Thus, according to the invention, it is expedient that in a multi-channel multiplexer input port, an output port, M outlet ports and M introductory ports were performed using optical fibers.

The invention is further explained in the description of examples of implementation of the multi-managed optical multiplexer input/output with dynamic functionality according to the invention and the accompanying drawings on which is shown:

Figa diagram of one stage of the EMC;

Figb - conventional single-stage image of the EMC shown in Figa;

Figa diagram of two stage of the EMC;

Figb - conditional two-stage image of the EMC shown in Figa;

Figa diagram of the modules of the EMC used to separate channels on odd and even;

Figb - cosmetic multistage MTS, shown in Figa;

Figa diagram of the modules of the EMC to combine odd and even channels;

Figb - cosmetic multistage MTS, shown in Figa; Figa scheme managed optical multiplexer I/o t-OADM;

Figb - cosmetic-managed optical multiplexer I/you the ode t-OADM, shown in Figa;

Figa scheme managed optical demultiplexer t-Demux;

Figb - cosmetic-managed optical demultiplexer t-Demux shown in Figa;

Figa scheme managed optical multiplexer t-Mux;

Figb - cosmetic-managed optical multiplexer t-Mux shown in Figa;

Fig diagram of multi-channel OADM with dynamic functionality according to the invention, used in the mode reconfigurable I/o, which uses t-OADM optical demultiplexer and multiplexer with fixed spectral characteristics;

Figure 9 - diagram of the multi-channel OADM with dynamic functionality according to the invention, used in managed mode I/o, which uses t-OADM, t-Demux and t-Mux.

While the accompanying drawings and described embodiments of the invention do not limit the application of the invention without going beyond the scope of this invention.

According to the invention, a key element for the functional units included in a multi-channel OADM with dynamic functionality according to the present invention is unbalanced interferometer Mach-Zehnder or as agreed to call him, one stage of the EMC.

Single stage of the EMC can be done is n by using various components and technologies, including, using fiber-optic splitters, beam splitters, mirrors, prisms, polarizers, and other items. The best option for multi-channel OADM with dynamic functionality according to the present invention is a single stage of the EMC in the planar version.

On Figa shows a schematic depiction of the waveguide single-stage variant of the EMC 10, its conventional image shown in Figb. The device 10 is placed on the same substrate 11, where is the cascade of the EMC 12 is formed located between the first 13 and second 14 splitters the two arms 12-1 and 12-2 formed by waveguides of unequal length l1and l2, respectively. The coupling coefficients k1and k2splitters 13 and 14 are equal and divide the optical power 50/50. The single-stage EMC 10 has conclusions a and b on one side and conclusions C and d on the other side.

This single stage of the EMC 10 shoulder 12-2 contains the device 15 phase shift, which introduces additional phase shift φ in the phase of the passing waves and is a managed element that is used to adjust the spectral characteristics.

The magnitude of the phase shift φ is controlled by thermo-optical or electro-optical effect using an electric current or voltage. Accordingly, the device 15, a phase shift which can be manufactured using thermo-optical material, for example, silicone, or electro-optic material such as lithium niobate (LiNbO3) or gallium arsenide. Such phase shift device known in the art spectral multiplexing as a tool to adjust the spectral characteristics of optical filters based on the EMC, and are also used in other devices, modulators and switches.

When the input port and the radiation unit capacity of the intensity of light at the two output ports c and d can be expressed by using the transfer factors ToAC(ν,φ) and Kad(ν,φ):

where D=2πnΔLν/c is the phase delay due to different optical length

shoulders 12-1 and 22-2; ΔL=l1-l2; n is the refractive index of the material, ν is the optical frequency and C is the speed of light in vacuum.

When excited through port b of the light intensity in the same output ports C and d can be represented using the transfer factors Tob(ν,φ) and Kbd(ν,φ):

Consider any interval of frequencies v (wavelengths A,), the coefficients of transmission (1)÷(4) be the spectral characteristics of single-stage of the EMC. As you can see, the spectral characteristics (1)÷(4) are periodic functions of the light frequency ν (idline wave λ), the difference of the lengths of the shoulder ΔL, the refractive index n and the phase shift φ.

For the health of a single stage of the EMC significant following properties:

- the distance between adjacent extrema in the spectral characteristics (1)÷(4) in units of optical frequency Δν and in units of wavelengths Δλ equal to:

and

- transfer coefficients of the (1)÷(4)corresponding to the optical transition radiation from a single input port (port a or b) two output ports (ports C or d), differ in phase by π;

the transmission ratios when replacing the two indices do not change, that is,

Kad(ν,φ)=Kb(ν,φ) and KAC(ν,φ)=Kbd(ν,φ);

- changing the value of the phase shift φ, it is possible to modify the spectral characteristics (1)÷(4)by sliding them along the axis of the frequencies (wavelengths); this leads, in particular, when the change of the phase shift δφ=±π inversion of the signals at the outputs;

the transmission ratios are not changed when the permutation of the indices, i.e. single stage of the EMC is a reversible device.

In turn, from these properties it follows that when input single stage of the EMC optical signal containing multiple channels, frequencies (wavelengths) which coincide with the position of the extrema in the dependency ratios of the transmission frequencies (wavelengths), the signal is s divided into two groups, shown on different outputs. One group contains an odd channels, the other group - even channels, in both groups the spectral interval between channels becomes two times greater than the input one stage of the EMC. Upon receipt of the same optical signal to another input of the odd and even channels at the outputs are swapped.

As one stage of the EMC is a reversible device, in another situation, when one input serves odd channels, and the other input serves the even channels, both channels are combined into one optical flow with a dense arrangement of channels.

Devices that perform the function of the separation channels on odd and even reverse function, combining odd and even channels into one stream, in foreign literature called interlibrary; in the literature there is no term for devices of similar purpose and in this text they are referred to as optical filters.

The distance between adjacent extrema Δν (or Δλ,) in the spectral characteristics for the real single stage of the EMC should be formed at the stage of its manufacture by selecting the corresponding difference of the lengths of the shoulder L and refractive index n. Managed the reorganization provisions of the extreme values of the coefficients of transmission relative to the set of frequencies {v } (or wavelengths {λ1}) must be made using the appropriate adjustment of the phase shift φ when using the optical filter as part of any specific device.

The lack of spectral characteristics of single-stage of the EMC are non-planar vertices and slowly falling edges of the spectral bands in a small spectral interval between channels may cause crosstalk between adjacent channels.

Another well-known disadvantage is that when a large difference of the lengths of the shoulder ΔL make the variance can be very high. These shortcomings limit the possibility of using single stage of the EMC in the devices used in communication systems with wavelength division multiplexing channels.

A significant improvement in spectral characteristics of optical filter devices and systems for spectral multiplexing provide, as you know (US, 6782158, In), two of the EMC, which can be done using fiber optic splitters, beam splitters, mirrors, prisms, polarizers, and in planar form, and contain this device phase shift.

On Figa shows a schematic depiction of the waveguide two-stage variant of the EMC 20, its conventional image shown in Figb. It uses three of the coupler 21, 22 and 23 with the step is eciently communication k 1, k2and k3accordingly, forming two single stage of the EMC 24 and 25. The device 20 is placed on a single substrate 26.

The first single stage of the EMC 24 is formed by two waveguides 24-1 and 24-2 of unequal length l24-1and l24-2, respectively. The second single stage of the EMC 25 is formed by two waveguides 25-1 and 25-2 of unequal length l25-1and l25-2, respectively. Phase delay D1=2πn(l24-1-l24-2)/λ and D2=2πn(l25-1-l25-2)/λ, linked by the relation: D2=2·D1.

In the EMC 24 and 25 are used, the phase shift device 27 and 28 made their phase shifts φ and ϕ, respectively. The two-stage EMC has conclusions a and b on one side and conclusions e and f on the other side.

The spectral characteristics of two of the EMC 20 it is easy to obtain analytically. For three splitters 21-1, 21-2 and 21-3, you must enter the matrix T(ki)(i=1,2,3), which relate the amplitude of light at the input and output parameters splitters:

and for the two single stage of the EMC 23 and 24 of the matrix T(D1) and T(D2):

and

Then the transmission matrix M(ν,φ,ϕ) are two of the EMC is determined by the product of the five matrices:

Since the transmittance of the two-stage of the EMC associated optical the e intensity output from the optical intensity at the entrance, for their definition, you should use expressions like:

From expressions (6)÷(9) can be obtained all the basic properties of two of the EMC. It is easy to check that two of the EMC at the input radiation through the ports ofandand b remains a device for splitting and merging odd and even channels. So, when applying the optical signal to the portanda two-stage IMTS channels will be divided into two groups containing one group of odd-numbered channels, and the other band - even channels. We note an important property, the remaining two of the EMC: when applying the optical signal to another input port (Figa), groups with odd and even channels are reversed on the output ports e and f.

The distance between adjacent extrema Δν and Δλ, in the spectral characteristics are also determined by the expressions (5), where ΔL is the path difference in the first cascade: ΔL=l24-1-l24-2. Still managed shift of spectral characteristics, now using two phase shifts φ and ϕ. To shift the spectral characteristics ToAE(ν,φ,ϕ) and Kaf(ν,φ,ϕ) along the frequency axis by the amount δv, you must use the appropriate devices phase shift change of the phase φ and ϕ:

and

WMS is about to see the (6)÷(9), when the input signal through the ports e and f lost the ability to split channels on odd and even and, accordingly, combining odd and even channels. This is a consequence of the fact that the matrix (6), (7) non-switched. Thus, two of the EMC are not reversible devices - two portandand b on the one hand can only be used as input ports,andtwo other ports e and f on the opposite side - just as the weekend.

The spectral characteristics of the two-stage EMC have a much better shape close to a rectangle with flat top and steep decline at the edges of the spectral bands. Therefore, two of the EMC used as the optical filter provides the best suppression of crosstalk and high isolation channels. However, insertion two-stage dispersion of the EMC remains large, and therefore use it as a filter in communication systems with high data rate is limited.

It is known (US, 6782158, B2)that the situation can be changed for the better when using filters obtained by cascading two of the EMC. In one embodiment, such devices can be used complementary to two of the EMC has the same transmittance, but opposite in sign to the dispersion. The complementarity of the two is Oschadny the EMC provides a certain ratio of the coupling coefficients k 1, k2, k3used two of the EMC.

On Figa shows one variant of the multi-stage EMC 30, which can be used to separate the odd and even channels; conventional multistage image of the EMC is shown in Figb.

The device 30 in a planar implementation hosted on the same substrate (chip) 31 and includes three complementary two-recognized: in the first stage used a two-stage EMC 32 type I, and in the second stage of the two stage of the EMC 33 and 34, both type I', respectively, with a different sign of the dispersion.

When the input signal in portandtwo of the EMC 32 channels, as usual, divided into two groups: in one group - odd channels, and the other even. In the second stage of the EMC 33 skips the odd channels at its output e and the EMC 34 transmits the even-numbered channels on its output f, thus, the odd and even channels are in foreign ports p and k, respectively. As the dispersion stage of the EMC 32 and each of the two-stage EMC 33 and 34 have opposite signs, then the variance of the multi-stage EMC 50 is offset is zero or almost zero.

On Figa shows one variant of the multi-stage EMC 40, which can be used to combine odd and even channels; cosmetic multistage IMTS given n is Figb. All device 40 in the planar executing placed on a single substrate (chip) 41 and includes three two-recognized: in the first stage uses two dual-stage of the EMC 42 and 43, both type I and second cascade - two of the EMC 44 type I', respectively, with the opposite sign of dispersion.

When the input odd and even channels, respectively, through the external port z and w, the EMC 42 and 43 just miss one odd and the other even-numbered channels on its output ports f. Combine the channels with the help of the EMC 44, and in the odd and even channels are output to the external port v. As the dispersion stage of the EMC 42 and 43 and each of the two-stage EMC 44 have opposite signs, then this provides a zero or near-zero dispersion of the entire device 40.

Let us now consider three functional units on the basis of the described optical filter, which in turn will be the basis for generating the multi-controlled multiplexer input/output according to the present invention. Each of the three functional units consider the example of one of the possible implementations.

Diagram of one embodiment of used controlled optical multiplexer 50 I/o is shown in Figa, its conventional image - Figb. The device 50 (hereinafter - t-OADM 50) is a Tr the stage setting structure and has an input port "In" output port "Out"port "Drop" output port "Add" input and includes three optical filter 51-1,51-2 and 51-3. The multiplexer further comprises an optical adder 52 with 4 inputs "1"÷"4" and one output 2. All three filters 51-1, 51-2 and 51-3 and the adder 52 is integrated on a single substrate 53. Connection filters are waveguides 54.

Dynamic management of controlled multiplexer 50 I/o is carried out by adjustment of the spectral characteristics of the three filters 51-1, 51-2 and 51-3 when applying to the device a phase shift of all three filters corresponding stresses. Management is done via an external controller (not shown)that is associated with optical filters electric bus 55.

Optical filters 51-1, 51-2 and 51-3 are connected in series with each other so that the output of one is connected to the input of another, the second output of each filter is connected to one of the optical inputs of the adder, the input of the first filter 51-1 is connected to the input port "In", the output of the last filter 51-3 connected to the output port "Drop", optical adder 52 another input is connected to the input port "Add", and the output from the output port "Out".

To explain the design and operation of these units, let us assume that the input port "In" controlled multiplexer I/o postopia the 8-channel optical signal, the center frequencies of the channels which {vi}=ν12,...,ν8and the frequency spacing between the channels at the input Δ=50 GHz. Since the spectral interval between channels is very small, the optical filters use multi-stages EMC shown in Figa. The distance between adjacent extrema in the spectral characteristics of the three optical filters should be as follows: Δν51-1=50 GHz, Δν51-2=100 GHz and Δν51-3=200 GHz. Accordingly, the difference of the lengths of the arms of the interferometers in the early stages of multi-stage of the EMC should be equal to: ΔL51-1=1000 μm, L51-2=500 μm, and ΔL51-3=250 μm (assuming n=1.5).

Without loss of generality assume that for one of the waves, let the waves ν3at some fixed values of the phases {φ∗n}=φ∗51-1that φ∗51-2that φ∗55-3and {ϕ∗n}=ϕ∗51-1,

ϕ∗51-2ϕ∗51-3(phase, respectively, in the first and second stages of the two-stage EMC) conditions, providing mileage wave V3 on the route from the input port "in" output port "Drop".

Work t-OADM 50 when these phases {φ∗n} and {ϕ∗n} as follows. Optical filter 51-1 first stage separates the channels received at the input port "In"into two groups - group odd waves ν1the 3, ν5and ν7that are directed to the optical filter 51-2 second stage, and the group of even-numbered waves ν2, ν4, ν6and ν8that are directed to the optical adder 52.

The process is repeated: first optical filter 51-2 again divides waves and sends waves ν3and ν7to the optical filter 51-3 third stage, and the waves ν1and ν5the adder 52; a third optical filter 51-3 divides coming to him two waves ν3and ν7. The result is the wave of the ν3held in the output port "Drop", and all other 7 waves arrive at the three inputs of the adder 52 and with it are in the output port "Out". Wave ν'3entered via port "Add", is supplied to the fourth input of the adder and also appears in the output port 52.

To any other channel was subjected to input/output, it is necessary in accordance with expressions (10) change the values of the phases {φn} and {ϕn}. For example, to switch input/output neighboring waves V4, it is necessary to change the phase shifts: δφ51-1=π δφ51-2=π/2, δφ51-3=π/4 and δφ51-1=2π δφ51-2=π δφ51-3=π/2.

If the input of the multiplexer begin to receive signals, the new channel frequencies which {ν'i} all shifted by the value of δν<Δν1=50 GHz, i.e. ν'ii+δν, tods, to enter/display the channels with the new optical carrier, again in accordance with the expression (10) to make corresponding corrections in the phase shifts {φ∗n} and {ϕ∗n}. For example, when the frequency shift channels on the value of δν=12,5 GHz to produce the input/output wave ν'3necessary changes phases should be: δφ51-1=-π/8, δφ51-2=-π/16, δφ51-3=-l/32 and δφ51-1=-π/4, δφ51-2=-π/8, δφ51-3=-π/8.

In the General case, the functional unit used in the present invention as t-OADM may differ from the t-OADM 50 number of stages N1in a multi-stage structure, the spectral interval between adjacent channels at the input Δνand the type of optical filters. For optical filters n1tier-n1=1,2,...N1the distance between adjacent extrema in the spectral characteristics must be installed as follows:

The functional characteristics of the device used as t-OADM is the area free of dispersion, which plays an important role in the present invention. Recall that the spectral characteristics of the optical devices can be cyclically repeated in a wide spectral interval. In this case, the repetition period, or the spectral the th range of F, within which there are no cyclic repetition of characteristics is called the free dispersion.

The concept of region-free dispersion with respect to t-OADM means that if the input signal contains multiple channels, the spectral range which does not exceed the value of the field-free dispersion F, the outlet port of this device will be only one channel. If the spectral range of channels at the input of the wider region free dispersion, into an output port "Drop" will be more than one channel; the spectral interval between the channels will then be equal to the value of F, that is, Δν=F. Similarly, through the port "Add" can be entered several new channel frequencies which coincide with the frequency of the output channels and the spectral spacing between the channels is equal to Δν=F.

For t-OADM 50 intended for selection of one channel of the multiple channels with spectral interval between the channels at the input Δνand having a multistage structure with the number of stages N1region free dispersion of F is:

The scheme used a managed optical demultiplexer 60 (hereinafter - t-Demux 60) according to the present invention is shown in Figa, conditional image shown in Figb.

Port ΣDemuxis used as input, eight ports C1÷C8 - individual output channels. Connect the optical filters of all three levels is the waveguides 65 formed on the substrate. Dynamic management managed demultiplexer 60 is accomplished by adjustment of the spectral characteristics of the optical filter feeding device phase shift contained in all the filters, the respective voltages. Management is done via an external controller (not shown)that is associated with optical filters electric bus 66.

To explain the operation of t-Demux 60, suppose that on input ΣDemuxcomes in 8-channel signal with the spectral interval between adjacent channels Δν=400 GHz.

As you pass the optical signal in t-Demux 60 from one step to the next level spectral spacing between channels is twice the Ira. For the filter 61 of the first stage of the spectral interval between channels minimum, for filters 63-1 to 63-4 third stage - on the contrary, the maximum and filters 62-1 and 62-2 of the second stage of the spectral interval - intermediate. Therefore, the requirements to the characteristics of various filters. As optical filters in this example can be used: in the first stage - multi-stage of the EMC (Figa), in the second stage of two stage of the EMC (Figa) and the third one stage of the EMC (Figa).

The distance between adjacent extrema in the spectral characteristics of the optical filters in the three stages of the device in question is selected as follows: for the multi-stage EMC 61 ∆ F61=400 GHz, for two of the EMC 62-1 and 62-2 Δν62-1=Δν62-2=800 GHz for the single-stage EMC 63-1 to 63-4 Δν63-1=Δν63-2=

Δν63-3=Δν63-4=1600 GHz. Accordingly, the path difference of the interferometer according to the expression (5) in the first cascade stage of the EMC, the components of the multi-stage EMC 61 equal to ΔL61=250 μm, in the first cascade stage of the EMC 62-1 and 62-2 the path difference ΔL is62-1=ΔL62-2=125 μm for the single-stage EMC 63-1 to 63-4 the path difference ΔL is64-1=ΔL64-2=ΔL64-3=

ΔL64-4=62.5 μm.

Obviously, at some fixed phase shifts in the first and second stages used the MC {φ∗ n} and {ϕ∗n} it is possible to provide the mode of dividing the channels into groups containing odd and even channels. In this state, the t-Demux 60 functions as a conventional demultiplexer with fixed frequency channels.

Optical signal containing eight channels, the center frequencies of the channels which {ν1}=ν12,...,ν8goes to the entrance. The modules of the EMC 61 divides the channel (wavelength) for odd ν1, ν3, ν5and ν7and even ν2, ν4, ν6and ν8that are directed to the two-stage EMC 62-1 and 61-2. Two of the EMC 62-1 and 61-2 again divide the incoming wave to them, at this stage of the EMC 62-1 sends waves ν1and

ν5to the single-stage EMC 63-1 and waves ν3and ν7- single-stage the EMC 63-2, and two of the EMC 62-2 sends waves ν2and ν6to the single-stage EMC 63-3 and waves ν4and ν8- single-stage the EMC 63-4. At last the third stage all the waves are completely separated and displayed individually on separate ports in accordance with table 1.

Table 1
Distribution channels output ports
Output portC1C2C3 C4C5C6C7C8
The carrier frequency of the channelν1ν5ν3ν7ν2ν6ν4ν8

Now suppose that the input of the control t-Demux 60 receives signals, new Central frequency channels which {ν'i} all shifted by the value of δν<Δν2=400 GHz.

To amultiplicity channels with new optical carrier according to a separate output ports, it is necessary to make changes phases {φ∗n} and {ϕ∗n} in accordance with the expression (10). For example, to switch to demultiplication channels whose frequencies are shifted by the value of δν=50 GHz, it is necessary to change the phase shifts as follows: δφ61=-π/8, δφ62-1=δφ62-2=-π/16, δφ63-1÷δφ63-4=-π/32. The distribution channels to the output ports remains the same, and the channel with carrier frequency ν'1will be displayed in the port C1, channel ν'5in port C2.

In General constructive perform t-Demux parameters, then the "1×2 M" in the multistage tree structure of the optical filters may differ from device 60 by the number of steps M, the spectral interval between adjacent channels at the input Δνand the type of optical filters. For optical filters n2tier-n2=1,2,...M distance between adjacent extrema in the spectral characteristics should be set equal to

The third functional device 70 has a purpose, opposite in relation to the appointment of the functional device 60, and is used to combine the channels. Two functional units 60 and 70, discussed below intended for multi-channel OADM with dynamic behavior must be compatible. This means that the inputs of the functional device 70 must be made channels, carrier frequencies which coincide with the frequencies of the channels at the outputs of the functional device 60, and the spectral interval between channels should be like t-Demux 60.

The scheme used a managed optical multiplexer (hereinafter - t-Mux 70) according to the present invention is shown in Figa, cosmetic - Figb.

t-Mux 70 is a multi-stage structure of type "tree" on seven) the ski filters.

Four optical filter 71-1 to 71-4, which constitute the first stage of the multistage structure, its output ports connected to two optical filters 72-1 and 72-2, components of the second stage, which in turn are connected to its output ports with another optical filter EMC 73, which is the third stage. The entire device is fabricated on the same substrate 74.

Eight ports B1 to B8 are used to enter each of the eight channels, port ΣMicahserves as the General output port. Connect the optical filters of all three levels is the waveguides 75 formed on the substrate 74.

Dynamic management t-Mux 70 is accomplished by adjustment of the spectral characteristics of the seven optical filter feeding device phase shift contained in all of the optical filters corresponding stresses. Management is done via an external controller (not shown)that is associated with optical filters electric bus 76.

In the t-Mux 70 as the passage of the optical signal from one step to the next level spectral intervals between the channels become twice already. Optical filters 71-4÷71-4 in the first stage of the spectral interval between channels maximum, the optical filter 73, on the contrary, minimum. Poet of the requirements for the characteristics used in the respective steps of different optical filters. As optical filters in this example can be used: in the first stage is a single stage of the EMC (Figure 1 (A), in the second stage of two stage of the EMC (Figa) and third modules of the EMC (Figa).

In accordance with the fact that t-Mux 70 must be compatible with the controlled demultiplexer t-Demux 60, the distance between adjacent extrema in the spectral characteristics of the optical filters in the three stages of the device in question should be the following: for single stage of the EMC 71-1 to 71-4 Δν71-1=Δν71-2=Δν71-3=Δν71-4=1600 GHz, for two of the EMC 72-1 and 72-2 - Δν72-1=Δν72-2=800 GHz and for the multi-stage EMC 63 Aν73=400 GHz.

You can see that the design of the t-Mux 70 differs from the described t-Demux 60 only used the multi-stage EMC: in one case is the multi-stage EMC (Figa), and in the other case, the multi-stage EMC (Figa). The process of aggregation performed using the t-Mux 70 is opposite to υ separation of the channels discussed above in t-Demux 60.

In General, the design of the t-Mux configuration "2M×1" in the form of a multistage tree structure of the optical filters may be different from the t-Mux 70 number of steps M, the spectral interval between adjacent channels at the output Δνand type optical the filters. For optical filters

n3=tier when n3=1,2,...M distance between adjacent extrema in the spectral characteristics should be set equal to

The scheme is one of the options, multi-channel OADM with dynamic functionality according to the invention is shown in Fig. This device is intended for use in an optical system using wavelength division multiplexing as ROADM when the total number of channels in the optical system 64, the spectral interval between adjacent channels Δν0=50 GHz, with configurable input/output subject to 8 channels.

Multi-channel OADM 80 with dynamic functionality based on t-OADM described above (Figa). This device, designated as 81-1, has an area free of dispersion in 8 times less than the spectral range of the optical signal at the input.

This uses a pair of devices: optical demultiplexer 81-2 configuration "1×8" and the optical multiplexer 81-3 configuration "8×1". Features a pair of demultiplexer/multiplexer must ensure demultiplication, multiplizieren 8 channels with spectral range Δν=Gg. Both devices demultiplexer 81-2 and the multiplexer 81-3 have fixed spectral x is tion and can be selected from an existing item such devices or specially made.

Three of the multiplexor device 81-1, 81-2 and 81-3 connected by optical fibers 82, while the output port "Drop" and input port "Add" t-OADM is connected to the input

ΣDemuxthe optical demultiplexer and the output ΣMicahoptical multiplexer, respectively. The input port 83 and the output port 84 is made in the form of optical fibers and connected, respectively, to ports "In" and "Out" t-OADM. Eight output ports 85-1÷85-8 connected to the outputs C1 to C8 optical demultiplexer, and eight ports of entry 86-1÷86-8 connected to inputs B1 to B8 of the optical multiplexer. Ports o 85-1÷85-8 and input 86-1÷86-8 made in the form of fibers. The device 80 also includes a controller 87, from which the electric bus 88 to controls t-OADM served control voltage {Ut-OADM}.

The input optical signal containing 64 channels, frequencies which correspond to the ITU-Standard received at the input of t-OADM. Since the area is free of dispersion t-OADM less than the spectral range of the optical signal at the input 83, port "Drop" displays 8 channels in one of the 8 combinations are shown in table 2. The specific combination of channels set control voltages {Ut-OADM}. All other channels are in the output port 84.

Table 2
Combination of channels, displaying the x in the port "Drop" device 81-1
Combination of channelsChannel numbers
1st1, 9, 17, 25, 33, 41, 49 57
2nd2, 10, 18, 26, 34, 42, 50 and 58
......
8th8, 16, 24, 32, 40, 48, 56 64

Eight channels with port "Drop" device 81-1 fed to the input of the optical demultiplexer 81-2, with which the channels are displayed separately from each other in the output ports 85-1÷85-8. At the same time instead of derived channels using an optical multiplexer 81-3 may introduce new 8 channels. Thus, of the 64 channels can be entered/displayed any of the 8 combinations of channels.

Diagram of another embodiment of performing multi-channel OADM with dynamic functionality according to the invention is shown in Fig.9. This device is intended for use in an optical system using wavelength division multiplexing as t-OADM. The total number of channels in the optical system 64, channel frequencies {ν'i} can be reconstructed, but the spectral interval between channels Δν0=50 GHz remains constant, and managed input/output subject to 8 channels.

Multi-channel OADM 90 with dynamic is unctionality built on t-OADM (Figa) and the optical demultiplexer and the multiplexer with tunable spectral characteristics, as using the above t-Demux configuration "1×8" and t-Mux configuration "8×1" (Figa and Figa).

Three of the multiplexor devices in the integrated optical performance are hosted on the same substrate 91: t-OADM 92-1, t-Demux 92-2 configuration "1×8", and t-Mux 92-3 configuration "8×1". They are connected by waveguides 93 formed on the common substrate 91. This outlet port "Drop" and input port "Add" t-OADM is connected to the input ΣDemuxt-Demux 92-2 and output ΣMicaht-Mux 92-3, respectively.

Multi-channel OADM 90 with dynamic functionality has an input port 94, the output port 95 which are connected by waveguides with ports "In" and "Out" t-OADM 92-1. Eight output ports 96-1 to 96-8 connected to the outputs S1÷8t-Demux 92-2, and eight ports of entry 97-1÷97-8 with inputs B1÷B8 t-Mux 92-3.

All external leads, that is, the input port 94, the output port 95, ports 96-1 to 96-8 o ports 97-1÷97-8 entry is made in the form of fibers. The device 90 also includes a controller 98, from which the electric bus 99 to the controls of three functional subsystems are served control voltage {Ut-OADM}, {UDemux} and {UMicah}.

The input optical signal containing a 64 channel, is fed to the input t-OADM 92-1. On this same device serves a control voltage {Ut-OADM}corresponding to the output port "Drop" to 8 channels of 64 with frequencies {ν'i} in one of the combin who were table 2. All other channels are in the output port 95.

Eight channels are routed to the input of the optical demultiplexer 92-2, with which the channels are displayed separately from each other in the output ports 96-1 to 96-8. At the same time instead of derived channels using an optical multiplexer 92-3 may introduce new 8 channels. While these two devices need to apply control voltages {UDemux} and {UMicah}providing demultiplication, multiplizieren, respectively, 8 output/input channels whose frequencies are chosen from the set {ν'i}.

Thus, it can be entered/displayed any of the 8 combinations of channels present at the input multi-channel OADM with dynamic functionality 64 channels with a frequency channels {ν'i}.

The device 90 can also be used in mode reconfigurable I/o 8 channels when you want to display/enter 8 set of channels 64 channels with fixed frequency channels. In this mode the control voltage {UDemux} and {UMicah} should be once installed properly, ensuring that the fork/join channels with frequencies corresponding to ITU-Standard. Output control/input 8-set channels in this case should be done by corresponding changes in t is like control signals {U t-OADM}.

Multi-channel OADM with dynamic functionality, intended for use as a ROADM or as t-OADM in any particular optical communication system may differ from the described devices 80 and 90. In the General case, the parameters included in a multi-channel OADM with dynamic functionality of the functional units of three types (t-OADM, Demux and Mux) are determined by the total number of channels in the optical system 2Nwhen N≥2, the spectral interval between adjacent channels Δν0and the number of channels to be input/output 2M(M is an integer with 1≤M<N. the Main parameters of the three functional units, taking into account the compatibility of these devices are given in table 3.

The infinity symbol "∞" in two positions in table 3 correspond to the fact that through the appropriate ports of these devices is displayed or entered only one channel. The number of possible combinations of input/output channels - 2N-M.

The use of integrated optical technologies for manufacturing seems to be the decisive factor for multi-managed optical multiplexers I/o according to the present invention meet the requirements for devices of similar purpose: had the opportunity in the ode/o a large number of channels, were resistant to external influences, had a high speed. The use of a uniform standard elements of structure in single-stage and/or two-stage and/or multi-stage IMTS - allows the use of automated manufacturing operations, which will ensure high performance and relatively low cost of manufacture multiplexers.

Except for use in optical communication networks, multi-channel OADM with dynamic functionality according to the invention may have other uses, for example, in multi-channel systems, sensors, optical filtering in analog systems for various purposes.

The examples explain the principle of operation, characteristics and possible options for the design of the present invention. Specialists in the field of fiber-optic communication systems should be obvious that within the framework of the present invention there may be other modifications and alternatives design multi-channel OADM with dynamic functionality according to the invention, is not beyond the scope of the claims.

Multi-channel OADM with dynamic functionality according to the present invention can be used in fiber-optic lines and communication systems with spectral TP is of the channels, including trunk lines, using DWDM technology, and in regional, urban and local communication systems using CWDM technology.

Multi-channel OADM with dynamic functionality according to the present can be implemented using existing integrated optical technologies.

1. Multi-managed optical multiplexer input/output with dynamic functionality for fiber-optic communication systems with wavelength division multiplexing 2Nchannels when N is an integer and N≥2 for the spectral interval between adjacent channels Δν0for I/o 2Mchannels when M is an integer with 1≤M<N, having one input port, one output port, 2Moutput ports, 2Mports input and including:
managed optical multiplexer input/output providing the output of the 2Mchannels in one Drop port of the output and input of new 2Mchannels on carrier frequencies derived channels in one port Add entry;
the optical demultiplexer configuration 1×2M"connected to its input port ΣDemuxwith the Drop port of the conclusion of the specified managed optical multiplexer input/output,
the optical multiplexer configuration "2M×1", connected to its output port ΣMuxport Add entry specified UE is supplied optical multiplexer input/output,
a controller for supplying control voltages to the controls, electrically associated with the specified controllable optical multiplexer input/output.

2. Multi-channel multiplexer according to claim 1, characterized in that the specified managed optical multiplexer input/output is:
(N-M)-stage structure, containing in each stage one optical filter having one input and two outputs, made with the possibility of a managed realignment transmission ratios, characterized in n1tier-n1=1,2,...,(N-M) frequency interval between adjacent extrema in the dependency ratios of the transmission frequency Δνn1=2n1-1Δν1;
optical adder having N-M+1 inputs and one output connected to the output port Out.

3. Multi-channel multiplexer according to claim 2, characterized in that the specified (N-M)-stage structure:
the optical filter of each stage except the last stage, one of the outputs connected to the input of the optical filter respectively subsequent stage and the other output is connected to one of inputs of the optical adder;
the optical filter of the first stage to its input coupled to the input port In;
the optical filter of the last stage one output connected to another one of the input optical adder, and another output connected to the ORT Drop output;
optical adder another input is connected to the Add port of entry;
the optical output of the adder connected to the output port Out.

4. Multi-channel multiplexer according to claim 1, characterized in that is used to control the I/o channels in a reconfigurable manner, in the optical demultiplexer and the multiplexer are fixed spectral characteristics.

5. Multi-channel multiplexer according to claim 1, characterized in that is used to control the I/o channel in the VFO mode, the optical demultiplexer and the multiplexer are tunable spectral characteristics and the controller is electrically connected with the specified optical demultiplexer and multiplexer.

6. Multi-channel multiplexer according to claim 5, characterized in that the optical demultiplexer includes an M-stage structure of type "tree"containing each n2tier-n2=1,2,..., M2n2-1optical filters having at least one input and two outputs, made with the possibility of a managed realignment transmission ratios, characterized in n2tier-frequency interval between adjacent extrema in the dependency ratios of the transmission frequency equal to Δνn2=2n2+N-M-1Δν1.

7. Mnookin the local multiplexer according to claim 6, characterized in that the specified optical demultiplexer in the specified M-step the structure of one of the inputs of the optical filter of the first stage is connected to the input port ΣDemuxeach of the two outputs of the optical filter of the last stage is connected to one of the output ports and the optical filters in each stage, except the last, are connected to each of two outputs to the input of one of the optical filters next level.

8. Multi-channel multiplexer according to claim 5, characterized in that the optical multiplexer includes an M-stage structure of type "tree"containing each n3tier-n3=1,2,...,M is not less than 2M-n3optical filters having two inputs and at least one output made with the possibility of a managed realignment transmission ratios, characterized in n3tier-frequency interval between adjacent extrema in the dependency ratios of the transmission frequency Δνn3=2N-n3·Δν1.

9. Multichannel multiplexer of claim 8, characterized in that the specified optical multiplexer in the specified M-step the structure of the two input optical filters of the first stage are connected to input ports, one output of the optical filter of the last stage connected to the output port ΣMuxand optical filters which each degree, but the first and last, are connected to each of the two inputs with the output of one of the optical filters of the previous stage, and one output with one of the inputs of one of the optical filters next level.

10. Multi-channel multiplexer according to any one of claim 2, 6, 8, characterized in that the optical quality of these filters are single-stage and/or two-stage and/or multi-stage unbalanced interferometers, Mach-Zehnder interferometers.

11. Multi-channel multiplexer according to any one of claim 2, 6, 8, characterized in that to control the setting of the transfer coefficients of the specified optical filters contain electro-optical or thermo-optical device of the phase shift.

12. Multi-channel multiplexer according to claim 1, characterized in that it is executed on the integrated optical technologies on a single chip.

13. Multi-channel multiplexer according to claim 1, characterized in that the input port, output port, M output ports and input ports are made using fiber optic cable.



 

Same patents:

FIELD: physics.

SUBSTANCE: multichannel controlled input/output optical multiplexer for fibre-optic communication systems with wavelength-division multiplexing of 2N channels, where N is an integer and N≥2, optical frequencies of which can be adjusted at constant spectral interval Δν0 between neighbouring channels, for input/output of 2M channels, where M is an integer and 1≤M<N, has a controlled optical demultiplexer with 1×2M configuration, controlled optical multiplexer with configuration 2M×1, 2M controlled input/output optical multiplexers and a controller for controlling adjustment of spectral characteristics of the said demultiplexer, multiplexer and 2M input/output multiplexers.

EFFECT: provision for given transmission capacity of filtering devices in the multiplexer with possibility of input-output of channels with given frequencies through control of spectral characteristics of these filtering devices.

11 cl, 15 dwg, 3 tbl

FIELD: physics.

SUBSTANCE: controlled optical demultiplexer includes a multi-stage structure of optical filters, made with possibility of controlled adjustment of transmission coefficients, as well as a controller for controlling adjustment of transmission coefficients of optical filters. The optical filters used are single-stage asymmetrical Mach-Zehnder interferometres and/or two-stage asymmetrical Mach-Zehnder interferometres and/or multi-stage asymmetrical Mach-Zehnder interferometres. Electro- and thermo-optical phase shift devices serve for controlling adjustment of transmission coefficients of the optical filters. The multiplexer can made using integrated optical technology in form of a monolithic solid-state device.

EFFECT: demultiplexing channels in fibre-optic communication system with wavelength-division multiplexing of channels, optical frequencies of which can be adjusted at constant spectral interval between neighbouring channels Δv.

7 cl, 9 dwg, 2 tbl

FIELD: physics, communication.

SUBSTANCE: invention is related to optical communication equipment and may be used for emphasis of transmitted signals in channels of multiplexed signals on transmission route with points of inlet and/or outbranching, which considers relative reduction of signal/noise ratios between transmitted signals of different categories or groups of channels, i.e. express-channels and channels of outbranching or inbranching, or outbranching/inbranching. For this purpose average signal capacities of different channel groups are established relative to each other in order to achieve specified ratios of signal-noise in appropriate groups. Moreover, ratios of signal-noise are balanced inside group of channels in points of their completion. Control protocols are described for control of emphasis steps. Method is also applicable for point-to-point connections, and also for transparent optical networks.

EFFECT: higher noise immunity at lower ratios of signal/noise.

29 cl, 4 dwg

FIELD: information technologies.

SUBSTANCE: specified invention relates to the optical interconnection and is intended for traffic protection if completely optical net. Technology of compact submultiplexing along length of waves is applied in method and device. Submultiplexing segments number, on which system waves length are divided, is defined according current conditions of protected and unprotected traffic distribution in network. Specified device contains, at least, one wave composer from each point side and optical protection module and executed protection function of submultiplexing segments optical level, meets traffic requirements with multi-access, optimises usage of system recourses.

EFFECT: system capacity improvement with satisfying fractional traffic protection.

6 cl, 11 dwg

FIELD: optical communication systems.

SUBSTANCE: proposed demultiplexer that has waveguide layer, geodetic lens optically coupled with single-mode input optical fiber and with dispersion component in the form of ordered waveguide diffraction grating, and output geodetic lens optically coupled with dispersion component and with output waveguides, all formed on single substrate, is characterized in that all channel waveguides of dispersion component are equal in length and each channel waveguide has two sections of different thickness, length difference of respective sections for any pair of adjacent channel waveguides being constant value.

EFFECT: enhanced useful-signal optical power due to reduced precision of dispersion component manufacture; reduced crosstalk channel noise due to reduced regular and random phase errors.

1 cl, 2 dwg

FIELD: multichannel optical communications, possible use for transmitting and receiving signals.

SUBSTANCE: in device monochromator system is augmented with transmitting module and receiving module, which contain M protected channels for communication of transmitting side and receiving side, N working channels, switching device, which in accordance to switching request from monochromator system switches the signal from aforementioned working channel to aforementioned protecting channel, or switches signal on aforementioned protective channel back to aforementioned working channel, while M and N are natural numbers and M<N.

EFFECT: realization of independent protection mechanism for monochromator and decreased consumption of optical wave length resource.

2 cl, 6 dwg

FIELD: optics.

SUBSTANCE: integral optical circuit has a group of optical amplifiers, formed in integral optical circuit, and ordered wave duct grid, formed in integral optical circuit and connected to group of optical amplifiers, group of wave duct elements connected to outputs of aforementioned group of optical amplifiers, while aforementioned ordered wave duct grid has star-shaped branch element, connected to group of wave duct elements. Group of optical amplifiers and ordered wave duct grid are made on basis of silicon oxide.

EFFECT: improved power of optical signal, simplified assemblage and lower costs.

2 cl, 7 dwg

FIELD: optics.

SUBSTANCE: integral optical circuit has a group of optical amplifiers, formed in integral optical circuit, and ordered wave duct grid, formed in integral optical circuit and connected to group of optical amplifiers, group of wave duct elements connected to outputs of aforementioned group of optical amplifiers, while aforementioned ordered wave duct grid has star-shaped branch element, connected to group of wave duct elements. Group of optical amplifiers and ordered wave duct grid are made on basis of silicon oxide.

EFFECT: improved power of optical signal, simplified assemblage and lower costs.

2 cl, 7 dwg

FIELD: multichannel optical communications, possible use for transmitting and receiving signals.

SUBSTANCE: in device monochromator system is augmented with transmitting module and receiving module, which contain M protected channels for communication of transmitting side and receiving side, N working channels, switching device, which in accordance to switching request from monochromator system switches the signal from aforementioned working channel to aforementioned protecting channel, or switches signal on aforementioned protective channel back to aforementioned working channel, while M and N are natural numbers and M<N.

EFFECT: realization of independent protection mechanism for monochromator and decreased consumption of optical wave length resource.

2 cl, 6 dwg

FIELD: optical communication systems.

SUBSTANCE: proposed demultiplexer that has waveguide layer, geodetic lens optically coupled with single-mode input optical fiber and with dispersion component in the form of ordered waveguide diffraction grating, and output geodetic lens optically coupled with dispersion component and with output waveguides, all formed on single substrate, is characterized in that all channel waveguides of dispersion component are equal in length and each channel waveguide has two sections of different thickness, length difference of respective sections for any pair of adjacent channel waveguides being constant value.

EFFECT: enhanced useful-signal optical power due to reduced precision of dispersion component manufacture; reduced crosstalk channel noise due to reduced regular and random phase errors.

1 cl, 2 dwg

FIELD: information technologies.

SUBSTANCE: specified invention relates to the optical interconnection and is intended for traffic protection if completely optical net. Technology of compact submultiplexing along length of waves is applied in method and device. Submultiplexing segments number, on which system waves length are divided, is defined according current conditions of protected and unprotected traffic distribution in network. Specified device contains, at least, one wave composer from each point side and optical protection module and executed protection function of submultiplexing segments optical level, meets traffic requirements with multi-access, optimises usage of system recourses.

EFFECT: system capacity improvement with satisfying fractional traffic protection.

6 cl, 11 dwg

FIELD: physics, communication.

SUBSTANCE: invention is related to optical communication equipment and may be used for emphasis of transmitted signals in channels of multiplexed signals on transmission route with points of inlet and/or outbranching, which considers relative reduction of signal/noise ratios between transmitted signals of different categories or groups of channels, i.e. express-channels and channels of outbranching or inbranching, or outbranching/inbranching. For this purpose average signal capacities of different channel groups are established relative to each other in order to achieve specified ratios of signal-noise in appropriate groups. Moreover, ratios of signal-noise are balanced inside group of channels in points of their completion. Control protocols are described for control of emphasis steps. Method is also applicable for point-to-point connections, and also for transparent optical networks.

EFFECT: higher noise immunity at lower ratios of signal/noise.

29 cl, 4 dwg

FIELD: physics.

SUBSTANCE: controlled optical demultiplexer includes a multi-stage structure of optical filters, made with possibility of controlled adjustment of transmission coefficients, as well as a controller for controlling adjustment of transmission coefficients of optical filters. The optical filters used are single-stage asymmetrical Mach-Zehnder interferometres and/or two-stage asymmetrical Mach-Zehnder interferometres and/or multi-stage asymmetrical Mach-Zehnder interferometres. Electro- and thermo-optical phase shift devices serve for controlling adjustment of transmission coefficients of the optical filters. The multiplexer can made using integrated optical technology in form of a monolithic solid-state device.

EFFECT: demultiplexing channels in fibre-optic communication system with wavelength-division multiplexing of channels, optical frequencies of which can be adjusted at constant spectral interval between neighbouring channels Δv.

7 cl, 9 dwg, 2 tbl

FIELD: physics.

SUBSTANCE: multichannel controlled input/output optical multiplexer for fibre-optic communication systems with wavelength-division multiplexing of 2N channels, where N is an integer and N≥2, optical frequencies of which can be adjusted at constant spectral interval Δν0 between neighbouring channels, for input/output of 2M channels, where M is an integer and 1≤M<N, has a controlled optical demultiplexer with 1×2M configuration, controlled optical multiplexer with configuration 2M×1, 2M controlled input/output optical multiplexers and a controller for controlling adjustment of spectral characteristics of the said demultiplexer, multiplexer and 2M input/output multiplexers.

EFFECT: provision for given transmission capacity of filtering devices in the multiplexer with possibility of input-output of channels with given frequencies through control of spectral characteristics of these filtering devices.

11 cl, 15 dwg, 3 tbl

FIELD: information technologies.

SUBSTANCE: device for fiber-optic communication system with wavelength-division multiplexing 2N channels where N is integer and N≥2 with spectral interval between adjacent channels Δv0 for performing input/output of 2M channels where M is integer and 1≤M<N, has one entering port, one exiting port, 2M output ports, 2M input ports and contains: controlled optical input/output multiplexer, optical demultiplexer of "1×2M" configuration, optical multiplexer of "2M×1" configuration and controller. This device can be used as multichannel controlled or multichannel reconfigurable optical input/output multiplexer.

EFFECT: performing input and output of multiple channels from optical signal with channel wavelength-division multiplexing using controlled dynamic filtering elements capacity restructuring.

13 cl, 16 dwg, 3 tbl

FIELD: physics.

SUBSTANCE: invention is designed for fibre optic lines of optical ATS (OATS) for broadband city and inter-city video-telephone, multimedia and telephone communication. The multiplexing device has an optical channel on several repeatedly used prisms which is common for all or for a large number of fibre optic lines of city and intercity OATS. In a subscriber access system with capacity of up to 80000 channels, one device will multiplex into a main line with average density of up to 500-1000 channels from terminal lines with low density Δλ=1 nm, and a terminal device will multiplex into a line with low density of up to 50 channels from subscriber terminals.

EFFECT: design of optical multiplexing devices which are easy to adjust to any range from visible to infrared waves and to any wavelength in that range.

3 cl, 4 dwg, 3 tbl

FIELD: physics.

SUBSTANCE: controlled optical multiplexer includes a multiple-step structure of filters having elements for controlled adjustment of transfer constants. The optical filters used are asymmetrical Mach-Zehnder interferometres: single-stage and/or two-stage, and/or multistage. Electro-optical or thermo-optical phase-shift devices serve for controlled adjustment of transfer constants of the optical filters. The multiplexer can be made on integrated-optical technology in form of a monolithic solid-state device.

EFFECT: controlled multiplexing of channels in the fibre optic communication system with wavelength-division multiplexing of channels, whose optical frequencies can be adjusted for constant spectral interval neighbouring channels Δν.

7 cl, 9 dwg, 2 tbl

Up!