WO2012133977A1

WO2012133977A1 - Aggregation wavelength division multiplexing node module

Info

Publication number: WO2012133977A1
Application number: PCT/KR2011/002862
Authority: WO
Inventors: 이태형; 이형재; 김태훈; 유병권
Original assignee: (주)포인테크
Priority date: 2011-03-28
Filing date: 2011-04-21
Publication date: 2012-10-04
Also published as: KR20120109870A

Abstract

The present invention relates to a configuration of and a method for manufacturing a wavelength division multiplexing node module having aggregated, as optical components used in a wavelength division multiplexing (WDM) node, a wavelength multiplexer (MUX), a wavelength demultiplexer (DMX), and a channel monitor. The aggregation wavelength division multiplexing node module is configured to: use two arrayed waveguide grating devices manufactured on one aggregation optical device chip, one as a wavelength MUX and the other as a wavelength DMX; couple, to an output portion of the arrayed waveguide grating device used as a wavelength DMX, a chip manufactured with an aggregation optical light tap coupler for diverging a part of an outputting light in array; and composing a photodetector array on the output to comprehend the signal status of each of communication channels. In addition, the arrayed waveguide grating devices used as a wavelength MUX and a wavelength DMX comprise a temperature-nondependent arrayed waveguide grating device so as to enable a stable operation unrelated to the change in the surrounding temperature.

Description

Integrated wavelength division multiplexing node module

In a Wavelength Division Multiplexing (WDM) communication system in which optical signals of several wavelengths are bundled and transmitted to one optical fiber and the optical signal of each wavelength is separated again at the receiving end, An arrayed waveguide grating (AWG) device using a planar waveguide technique is widely used as an element that is bundled with one optical fiber and separated into optical signals of respective wavelengths. In a wavelength division multiplexing communication, a node is a light source, a photodetector, a multiplexer (MUX), a demultiplexer (DMX), a channel monitor, And the like.

In a wavelength division multiplexing communication system in which optical signals of several different wavelengths are bundled and transmitted to one optical fiber and optical signals of respective wavelengths are separately received at the receiving end, a wavelength multiplexer for bundling several wavelengths into one optical fiber is transmitted A wavelength demultiplexer for separating optical signals of several wavelengths into respective wavelengths, and optical channel states such as the intensity, wavelength, and optical signal to noise ratio (OSNR) of the optical signals of the respective wavelengths transmitted It requires a channel monitor to identify. In such a WDM communication system, since there are dozens of communication channels, the same number of channel monitors are required to monitor the status of each channel. In addition, the wavelength characteristics of the optical waveguide thermal grating device, which is a wavelength multiplexing and wavelength demultiplexing device, vary greatly depending on the ambient temperature. In order to prevent this characteristic change, a method of controlling the temperature of the device is mainly used.

In order to perform wavelength division multiplexing in the wavelength division multiplexing communication system, core components such as a wavelength multiplexer, a wavelength demultiplexer, and a channel monitor are required except for a light source and a photodetector. In the past, a discrete device was used to form one optical waveguide lattice element used as a wavelength multiplexer and one optical waveguide lattice element used as a wavelength demultiplexer, a tap coupler as many as the number of wavelength channels used in the system, The optical fibers are connected to each other by using a photodetector as many as the number of channels, which is disadvantageous in that the modularization operation is cumbersome and bulky. In general, the optical waveguide thermal grating device used as a wavelength multiplexer and a demultiplexer has a characteristic in which the center wavelength of the filter moves according to the ambient temperature to be used, so that the temperature is controlled so that the characteristics do not change. Control is required.

Disclosure of Invention Problems to be Solved by the Invention The present invention has the disadvantages of increasing the volume and complexity of connection between optical fibers generated when one wavelength multiplexer, one wavelength demultiplexer, one tap coupler as many as the number of wavelength channels, The present invention is an invention constituted so as to constitute elements in an integrated form so as to simplify fabrication and reduce the volume dramatically. Also, the optical waveguide thermal grating device used as a wavelength multiplexer and a demultiplexer is configured to maintain constant characteristics even with temperature change, and to use the device without external temperature control.

When wavelength-division multiple nodes using individual devices are used, a large number of fusion splicing between optical fibers and connection between optical connectors are required, so that there is a disadvantage that the configuration is troublesome and occupies a large space. The present invention achieves integration and miniaturization in addition to easiness of fabrication by using such an integrated chip level device in the form of an array of connection points and implementing various connection points through the use of integrated chips or direct connection between chips. In addition, a wavelength demultiplexer and a wavelength demultiplexer that operate without temperature control using a temperature-independent optical waveguide thermal grating device are implemented to realize ease of use.

1 schematic diagram of an integrated wavelength division multiplexing node module

2 An example of the actual configuration of the integrated wavelength division multiplexing node module

FIG. 3 is a block diagram of an integrated optical tap combiner array chip

The present invention relates to a device used in one node in WDM communication. As shown in FIG. 1, in a package 101, a temperature independent wavelength multiplexer 102, a temperature independent demultiplexer 103, An array (tap coupler array) 104, a photo detector array 105, and a signal processing circuit 106 are integrated and configured.

2, two optical waveguide lattice elements fabricated on one chip 201 are respectively connected to a wavelength demultiplexer 207-206-205-204-203 and a wavelength demultiplexer 214- 215-216-217-218), the integrated configuration is obtained as compared with the case of using two separate chips. Further, the optical waveguide thermal grating device is configured to perform a temperature independent operation so that no separate temperature control is required. In FIG. 2, the single channel

optical waveguide sections

203 and 214 are separated from the chip 201 for adhesion independent of temperature, the substrates for

recombination

209 and 222 are adhered and fixed to the rest of the chip, After the alignment of the channel optical waveguide part is performed using the

coupling pillars

211 and 224 coupled to the temperature compensating

metal rods

212 and 225, the single channel waveguide part and the spacers 210, Channel optical waveguide part can be moved along the cut surface. The thus formed optical waveguide thermal grating device shifts the position of the single-channel optical waveguide (203, 214) through the thermal expansion and the thermal contraction of the metal rod due to the increase and decrease of the temperature so as to compensate for the wavelength change so that the wavelength is maintained Temperature independent operation. Then, the tap combiner array chips 219 fabricated by using the same planar waveguide fabrication technique as the fabrication method of the optical waveguide thermal grating device are directly aligned and bonded to the output of the optical waveguide thermal grating device used as a wavelength demultiplexer, The ease of manufacture and volume are reduced as compared with the case of using it. 3 shows the configuration of a tap combiner array chip. The intervals of the input units 302 of the tap combiner array are set to be the same as the intervals of the output unit of the optical waveguide thermal grating device used as the wavelength demultiplexer and the intervals of the

output units

306 and 307 of the tap array Arrays 220 are formed. For this purpose, a fan-out unit 303, a straight line unit 204, a directional coupling unit for branching light to a specific value between 1% and 10%, a main output waveguide unit 306, And a tap output waveguide unit 307. The optical wavelength of the individual optical signal detected by the photodetector through the individual optical wavelength of the optical signal passing through the individual port of the wavelength demultiplexer output section and the output port of the individual tap combiner of the tap combiner array is the same wavelength. Also in the combination of the tap combiner array 219 and the photodetector 221, the photodetector is used in an array form instead of an individual device, thereby facilitating fabrication and reducing the volume of the device. The optical detector is fabricated in a form coupled with an optical fiber, and an optical fiber array block 220 in which optical fibers coupled to the main output optical fiber and the optical detector are alternately arranged is manufactured and attached to the output portion of the tap combiner array 220. A circuit board is built and embodied so that the circuit can be configured to monitor the intensity of light detected by the photodetector in the system so that it can communicate with the outside.

In the present invention, the optical waveguide thermal grating device used as the wavelength multiplexer and the wavelength demultiplexer may be constituted by independent optical waveguide thermal grating device chips sharing the same substrate as in the embodiment, or by using an independent device chip having the respective substrates can do. Also, the tap combiner array provided at the output of the wavelength demultiplexer can be fabricated on a separate substrate outside the wavelength demultiplexer or on the same substrate as the wavelength demultiplexer.

The present invention is an invention realized by integrating the function of performing wavelength multiplexing and demultiplexing functions and monitoring the status of each wavelength channel in a wavelength division multiplexing optical communication system.

Claims

Temperature independent optical waveguide thermal grating device used as a wavelength multiplexer,

Temperature independent optical waveguide thermal grating device used as a wavelength demultiplexer,

A tap combiner array provided in an output section of the wavelength demultiplexer and branching a part of the output,

A photodetector array for monitoring the intensity of the tap combiner output;

And a wavelength division multiplexing node module
Temperature independent optical waveguide thermal grating device used as a wavelength multiplexer,

Temperature independent optical waveguide thermal grating device used as a wavelength demultiplexer,

A tap combiner array provided in an output section of the wavelength demultiplexer and branching a part of the output,

A photodetector array for monitoring the intensity of the tap combiner output;

An electric circuit board for mounting the photodetector array to process the electric signal from the photodetector and deliver it to the outside

And a wavelength division multiplexing node module
3. The method according to any one of claims 1 to 2,

Wherein the wavelength multiplexer and the wavelength demultiplexer are constituted by independent optical waveguide thermal lattice element chips each having a substrate.
3. The method according to any one of claims 1 to 2,

Wherein the wavelength multiplexer and the wavelength demultiplexer are constituted by an independent optical waveguide thermal grating device chip sharing the same substrate.
3. The method according to any one of claims 1 to 2,

And the tap combiner array provided at the output of the wavelength demultiplexer is fabricated on a separate substrate independent of the wavelength demultiplexer.
3. The method according to any one of claims 1 to 2,

And the tap combiner array provided at the output of the wavelength demultiplexer is fabricated on the same substrate as the wavelength demultiplexer.
3. The method according to any one of claims 1 to 2,

Wherein each tap output of the tap combiner array has a range of 1% to 10% of the main output.
3. The method according to any one of claims 1 to 2,

Wherein the optical wavelength of the individual optical signal detected by the optical detector through the individual optical wavelength of the optical signal passing through the individual port of the wavelength demultiplexer output unit and the output port of the individual tap combiner of the tap combiner array is the same wavelength. module