KR20070016888A - Optical add/drop multiplexer for Wavelength Division Multiplexing - Google Patents

Abstract

The optical insertion extraction apparatus according to the present invention includes first and second main optical lines connected to an optical communication system, and first and second extracting optical signals input through the first and second main optical lines into three different wavelengths. A first and second light insertion extracting groups connected to an optical signal in a wavelength region passing through the second light insertion extractor, the first and second light insertion extractors, and having a plurality of light insertion extractors, and from the first light insertion extractor. And a third optical insertion extractor for extracting an optical signal having a predetermined wavelength from the reflected optical signal, wherein the optical signal in the wavelength region inputted through the first main optical line but not extracted / synthesized by the optical insertion extractor is a first optical insertion. The light is sequentially reflected from each of the extractor and the second optical insertion extractor, and then output to the second main optical path.

Optical communication, optical insertion extractor, filter, insertion loss

Description

Optical add / drop multiplexer for Wavelength Division Multiplexing

1 is a schematic diagram showing a conventional optical communication technology,

Figure 2 is a schematic view showing a conventional light insertion extraction apparatus,

3 is a schematic view showing an optical insertion extracting apparatus of the present invention;

Figure 4 is a schematic view showing a first optical insertion extractor of the present invention.

Explanation of symbols on the main parts of the drawings

100: optical insertion extraction apparatus 1a, 1b: first and second main optical path

110: first optical insertion extractor 112a to 112d: first 1,2,3,4 optical path

114: first filter 115: second filter

130: third optical insertion extractor 134: third filter

140,150,160,170: 4 ~ 11 optical insertion extractor

144, 154, 164, 174: 4th to 11th filters

180: first optical insertion extraction group 190: second optical insertion extraction group

The present invention relates to an optical insertion extractor, and more particularly, to an optical insertion extractor for inserting / extracting an optical signal of multiple channels in an optical communication system of a wavelength division multiplexing method.

In general, optical communication using a wavelength division multiplex (WDM) scheme, as shown in FIG. 1, transmits an optical signal between an MUX / DeMUX, an optical cable connecting the same, and an MUX and DeMUX. Optical Add / Drop Multiplexer for receiving (Drop) is included. In this case, the optical insertion extractor transmits an optical signal corresponding to a predetermined wavelength region and reflects other optical signals, or an optical signal corresponding to a wavelength region greater than or smaller than a predetermined wavelength has a characteristic of reflecting other optical signals. The other optical signal that transmits and includes an edge filter having a characteristic of reflecting. Such filters are generally installed one by one in an optical insertion extractor, and a plurality of such optical insertion extractors are generally used according to their use environment.

FIG. 2 is a light insertion extraction apparatus including a plurality of optical insertion extractors as described above and extracting an input optical signal into optical signals of a total of five wavelength regions or transmitting optical signals of a total of five wavelength regions to an optical communication system. 10 is shown. Referring to this, the conventional optical insertion extractor 10 is composed of first to eleven optical insertion extractors 11 to 21, among which the first, second and eleven optical insertion extractors 11, 12, 21 Is for transmitting and receiving the optical signal of the first wavelength region, and the remaining third to tenth optical insertion extractors 13 to 20 are for transmitting and receiving the optical signal of the second wavelength region. The third to sixth optical insertion extractors 13 to 16 are provided to transmit and receive optical signals of third to sixth wavelength regions different from each other in the second wavelength region. The same applies to the extractors 17-20. In addition, each of the light insertion extractors (11 to 21) is provided with one filter. For reference, as described above, the first, second, and eleventh optical insertion extractors 11, 12, and 21 are installed in consideration of the wavelength region of the optical signal transmitted and received by each of the optical insertion extractors 11 to 21. The first filter is composed of a filter capable of transmitting the optical signal of the first wavelength region, and the filters used for the remaining light insertion extractors 13-20 are composed of a filter capable of transmitting the optical signal of the third to sixth wavelength regions. .

According to the conventional optical insertion extracting apparatus 10 having such a configuration, it is possible to extract optical signals of a total of five wavelength regions as described above. For example, the extraction of the optical signal in the sixth wavelength region is performed after the optical signal inputted to the first optical insertion extractor 11 is sequentially reflected by the first to fifth optical insertion extractors 11 to 15. The extraction is possible by being input to the optical insertion extractor 16. Meanwhile, the optical signals in the seventh wavelength region other than the first and second wavelength regions are sequentially reflected from the first to eleventh optical insertion extractors 11 to 21 and then transmitted to the optical communication system.

The conventional optical insertion extractor as described above enables the transmission and reception of optical signals for each of a plurality of wavelength regions through the optical insertion extractors 11 to 21. However, in the case of an optical signal that is not extracted by each of the optical insertion extractors 11 to 21 and is transmitted back to the optical communication system, the optical signal is transmitted to the optical communication system after several reflections are made by each of the optical insertion extractors 11 to 21. Therefore, there is a problem in that an optical signal is poor due to Express insertion loss. For example, when a reflection is made by each of the first to eleventh optical insertion extractors 11 to 21, a loss of 0.3 dB is typically generated in one reflection, so that the optical signal in the seventh wavelength region is returned to the optical communication system. In case of transmission, an insertion loss of 11 times 0.3dB, that is, 3.3dB is generated.

In order to solve such a conventional problem, conventionally, a method of grouping a plurality of optical insert extractors is used to minimize the above-described insertion loss, but in this case, structural limitations of each optical insert extractor using a single filter are used. There was a problem that can not obtain a satisfactory effect.

The present invention was devised to solve the above-mentioned problems, and can extract / synthesize optical signals in a plurality of wavelength regions while minimizing insertion loss for optical signals in wavelength regions other than the extraction / synthesis targets. Its purpose is to provide an insertion extraction device.

Optical insertion extraction apparatus according to the present invention for achieving the above object, the first and second main optical path connected to the optical communication system; A first filter for reflecting the optical signal in the first wavelength region and transmitting the optical signal in the second wavelength region among the optical signals inputted through the first and second main optical lines; and the second filter passing through the first filter. First and second optical insertion extractors having a second filter for reflecting the optical signal in the third wavelength region and transmitting the optical signal in the fourth wavelength region among the optical signals in the wavelength region; First and second optical insertion extractors connected to the first and second optical insert extractors to transmit and receive optical signals with the first and second optical insert extractors through an optical signal of the fourth wavelength region through which the second filter is permeable; A second light insertion extraction group; A third optical insert extractor having a third filter for transmitting the optical signal in the first wavelength region and connected to the first optical insert extractor, wherein the third optical insert extractor is connected to the first optical extractor. The optical signal may be sequentially reflected from each of the first optical insert extractor and the second optical insert extractor, and then output to the second main optical path.

According to a preferred embodiment of the present invention, each of the first and second optical insertion extractor, the first optical path connected to each of the first and second main optical path; A second optical path connecting the first and second light insertion extractors to each other; A third optical path connected to the third optical insert extractor; And a fourth optical path connected to each of the first and second light insertion extraction groups.

Here, each of the first and second light insertion extraction groups preferably includes a plurality of light insertion extractors capable of extracting the optical signal of the fourth wavelength region according to the size of the wavelength region.

Each of the first and second light insertion extraction groups may include fourth to seventh light insertion extractors connected in series so as to extract the optical signal of the fourth wavelength region into an optical signal of four wavelength regions. The seventh optical insertion extractor is more preferably connected to the fourth optical path via the sixth, fifth and fourth optical insertion extractors sequentially.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 shows a light insertion extraction apparatus 100 according to the present invention. Referring to this, the light insertion extractor 100 according to the embodiment of the present invention is the first and second light insertion extractors 110 and 120, the third light insertion extractor 130, the first and second The light insertion extraction groups 180 and 190 are included. For reference, reference numeral C denotes a melting point for connecting optical paths connecting optical insertion extractors 110 to 170 to transmit and receive optical signals.

The first optical insertion extractor 110 is connected to a first main optical line 1a connected to the optical communication system 1, and receives an optical signal input through the first main optical line 1a for the first, third and fourth wavelengths. It is separated into three optical signals of the area. To this end, the first light insertion extractor 110, as shown in Figure 4, the first and second light concentrator 111, 116, and the first and second filters 114, 115 It is comprised by installing along the longitudinal direction of the housing 119. Here, the first light focusing device 111 is input through the first light focusing unit 112 including the first to third light paths 112a, 112b and 112c and the first light focusing unit 112. And a first lens 113 for focusing the received optical signal into linear light. Here, the first optical path 112a is connected to the first main optical path 1a by fusion welding. The second optical focusing apparatus 116 is configured to focus the second optical focusing unit 117 including the fourth optical path 112d and the optical signal transmitted and received through the second optical focusing unit 117 with linear light. Two lenses 118. The first filter 114 reflects the optical signal of the first wavelength region among the optical signals input through the first optical focusing apparatus 111 to the second optical path 112b, and reflects the optical signal of the second wavelength region. It is provided to transmit. The second filter 115 is to separate the optical signal of the second wavelength region transmitted through the first filter 114 into an optical signal of the third wavelength region and the fourth wavelength region. Here, the optical signal of the third wavelength region is reflected by the second filter 115 and output through the third optical path 112c, and the optical signal of the fourth wavelength region 112d is the second optical concentrator 117. And the fourth optical path 112d. On the other hand, except that the second light insert extractor 120 is connected to the first light insert extractor 110 through the third optical path 112c and the configuration of the first light insert extractor 110 as described above and Since the same, detailed description thereof will be omitted here.

The third optical insert extractor 130 is connected to the first optical insert extractor 110 through the second optical path 112b, and includes a third filter 134 to extract the optical signal of the first wavelength region. The optical signal of the first wavelength region is different from the optical signal of the fourth wavelength region, and in this embodiment, the first wavelength region uses a wavelength region of about 1300 nm, and the second wavelength region has a wavelength of about 1500 nm. Use area.

The first light insertion extraction group 180 is connected to the first light insertion extractor 110 through the fourth optical path 112d to separate the optical signal of the fourth wavelength region into a plurality of optical signals for each wavelength region. To this end, in the present embodiment, the first light insertion extracting group 180 includes fourth to seventh light insertion extractors 140, 150, 160, and 170, and each of the light insertion extractors 140, 150, 160, and 170 is a fourth to seventh filter 144, 154, 164, 174. ), Extraction of a total of four optical signals, which are the fifth to eighth wavelength regions, is sequentially performed. On the other hand, except that the second light insertion extractor group 190 is the same as the first light insertion extractor 180 except that the eighth light insertion extractor 140 is connected to the second light insertion extractor 120 is the same The detailed description thereof will be omitted.

The operation of the light insertion extraction apparatus 100 according to the present invention described above will be described.

First, an optical signal output from the optical communication system 1 through the first main optical path 1a is input to the first optical insertion extractor 110 through the first optical path 112a. The optical signals of the first wavelength region among the optical signals input to the first optical insert extractor 110 are input to the third optical insert extractor 130 through the second optical path 112b and extracted, and the second wavelength is extracted. After the optical signal of the region is separated into the optical signals of the third wavelength region and the fourth wavelength region, the optical signal of the fourth wavelength region is input to the first optical insertion extraction group 180 through the fourth optical path 112d. The optical signal of the third wavelength region is input to the second optical insertion extractor 120 through the third optical path 112c. Here, the optical signal input to the first optical insertion extraction group 180 is separated into optical signals of the fifth to eighth wavelength regions by the fourth to seventh optical insertion extractors 140, 150, 160, and 170. Meanwhile, the second light insertion extractor 120 is connected to the second light insertion extraction group 190. The second light insertion extraction group 190 has the same structure as the above-described first light insertion extraction group 180. In this embodiment, since the optical signal is input through the first main optical line 1a, the fourth to seventh optical insertion extractors 140, 150, 160, and 170 of the second optical insertion extraction group 190 are externally provided. An optical signal in the fifth to eighth wavelength ranges is input. The optical signals of the fourth to seventh wavelength regions thus input are sequentially passed through the seventh, sixth, fifthth and fourthth optical insertion extractors 170, 160, 150, and 140 of the second optical insertion extractor 190. And then synthesized, and then input to the optical communication system 1 via the second main optical line 1b. If the optical signal is input through the second main optical line 1b, the first and second optical insertion extractors 110 and 120 operate in the opposite manner as described above, and the first and second optical insertion group 180) 190 are also operated opposite to each other.

On the other hand, the optical signal of the third wavelength region input to the second optical insert extractor 120 has the same configuration of the first optical insert extractor 110 and the second optical insert extractor 120, the second optical insert extractor ( Reflected by the first filter 114 of 120 is output to the optical communication system 1 via the second main optical line (1b). That is, when the optical insertion extraction apparatus 100 according to the present invention having the above-described configuration is used, the optical signal of the third wavelength region which is not necessary for separation / synthesis in the optical insertion extraction apparatus 100 is a first light path. It is transmitted after two reflections through the first and second light insertion extractors 110 and 120 from 112a to the second optical path 112b. For example, when the input loss due to the normal reflection is 0.3, the insertion loss is doubled by 0.3 to 0.6, and the insertion loss is reduced to 20% or less than the conventional case described above.

According to the optical insertion extraction apparatus according to the present invention described above, it is possible to extract / synthesize optical signals of a plurality of wavelength regions and to perform other wavelength regions simply by way of the optical insertion extraction apparatus without the above-mentioned extraction / synthesis. The insertion loss of the optical signal can be minimized.

While the invention has been shown and described with respect to preferred embodiments for illustrating the principles of the invention, the invention is not limited to the construction and operation as shown and described. Rather, those skilled in the art will appreciate that changes and modifications can be made to the present invention without departing from the spirit and scope of the appended claims. Accordingly, all such suitable changes and modifications and equivalents should be considered to be within the scope of the present invention.

Claims (4)

First and second chief optical lines connected to the optical communication system; A first filter for reflecting the optical signal in the first wavelength region and transmitting the optical signal in the second wavelength region among the optical signals inputted through the first and second main optical lines; and the second filter passing through the first filter. First and second optical insertion extractors having a second filter for reflecting the optical signal in the third wavelength region and transmitting the optical signal in the fourth wavelength region among the optical signals in the wavelength region; First and second optical insertion extractors connected to the first and second optical insert extractors to transmit and receive optical signals with the first and second optical insert extractors through an optical signal of the fourth wavelength region through which the second filter is permeable; A second light insertion extraction group; And a third optical insert extractor having a third filter for transmitting the optical signal in the first wavelength region and connected to the first optical insert extractor. The optical signal of the third wavelength region input through the first main optical line is sequentially reflected from each of the first and second optical insertion extractor and is output to the second main optical line Insertion extraction device. The method of claim 1, wherein each of the first and second light insertion extractor, A first optical path connected to each of the first and second main optical paths; A second optical path connecting the first and second light insertion extractors to each other; A third optical path connected to the third optical insert extractor; And And a fourth optical path connected to each of the first and second light insertion extraction groups. The method according to claim 1 or 2, Each of the first and second light insertion extraction groups includes a plurality of light insertion extractors capable of extracting the optical signal of the fourth wavelength region according to the size of the wavelength region. The method of claim 3, wherein Each of the first and second light insertion extracting groups includes fourth to seventh light insertion extractors connected in series with each other so as to extract an optical signal of the fourth wavelength region into an optical signal of four wavelength regions, And the seventh optical insertion extractor is connected to the fourth optical path via the sixth, fifth and fourth optical insertion extractors sequentially.

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