M398295 五、新型說明： 【新型所屬之技術領域】 尤指一種光通訊系 本創作係關於一種通訊系統， 統0 【先前技術】 * 树電__應用在現代已經越來越為普及，而 為了因應使用者的需求，電視節目也跟著越來越多，隨 著訊號的傳輸量增加以及雙向互動的服務出現，有線電 視網路已經朝向光纖到府或光纖到點的方向發展。 請參閱第m係為f知技術的光通信系統 架構。於光通“系統1〇〇中，發送端具有光發射機n 與12，並分別用以傳輸光信號L1與l2至同調光通信 (Wavelength Division Multiplexing ; WDM)模組 13，接 著，同調光通信模組13會將光信號L1與L2調制成為 _ 混合光信號L3傳輸至接收端主機14，以供接收端主機 14自混合光信號L3解調出光信號L4與L5，並供接收 端子機15與16接收。 然而，當光發射機11與12所發射出之光信號L1 與L2之波長差dl小於某個程度時，就會使光通信系統 100 發生光拍差干擾(Optical Beat Interference ; OBI)現 象’並使接收端主機14所解調出之光信號L4與L5存 在雜訊與底噪，導致系統的訊號雜訊比(Signal-to-noise ratio ; SNR)降低，嚴重時更可能導致光通信系統100 3 M398295 通訊中斷。 【新型内容】 本創作所欲解決之技術問題與目的： 緣此，本創作之主要目的係提供一種光通訊系 統，該光通訊系統係可利用接收端主機發送調制深度 控制訊號，藉以調整第一光發射機與第二光發射機所 發出之光訊號之調制深度，以改善系統的訊號雜訊比。 本創作解決問題之技術手段： 一種光通信系統係包含接收端主機、同調光通信 模組、第一光發射機與第二光發射機；接收端主機係 用以發送調制深度控制訊號；同調光通信模組係用以 接收並發送調制深度控制訊號至第一光發射機與第二 光發射機；第一光發射機，係具有第一調制深度控制 模組，用以調整第一光發射機所發射之第一光訊號之 第一調制深度；第二光發射機係具有第二調制深度控 制模組，用以調整第二光發射機所發射之第二光訊號 之第二調制深度；其中，同調光通信模組更用以將第 一光訊號與第二光訊號調制成混合光訊號傳送至接收 端主機，供其解析出第一光訊號與第二光訊號。 於本創作之一較佳實施例中，第一調制深度控制 模組可以包含數位可調式衰減器（Digital Variable Attenuator ; DVA)，且第二調制深度控制模組亦可包含 4 M398295 數位可調式衰減器。 β於本創作之另一較佳實施例中，接收端主機可以 是根據所解析出之第一光訊號之第一訊號雜訊比與第 二光訊號之第二訊號雜訊比而發送調制深度控制訊號。 本創作對照先前技術之功效： 相較於習知之光通訊系統，本創作於第一光發射 畚频第二料射機分別設置第—調制深度控制模^與 第二調制深度控制模組，並依據接收端主機所發送之 調制深度控制訊號改變第一光訊號之第一調制深度與 第二光訊號之第二調制深度，因此能夠於遠端即時的 改善光通訊系統的訊號雜訊比，並避免〇ΒΙ現象的發 生。 本創作所採用的具體實施例，將藉由以下之實施 例及圖式作進一步之說明。 【實施方式】 本創作係關於一種通訊系統’尤指一種光通訊系 統。以下茲列舉一較佳實施例以說明本創作，然熟習 此項技藝者皆知此僅為一舉例，而並非用以限定創作 本身。有關此較佳實施例之内容詳述如下。 請參考第二圖與第三圖，第二圖係為接收端主機傳 送調制深度控制訊號至第一光發射機與第二光發射機 之示意圖’第三圖係為第一光訊號、第二光訊號與混 5 M398295 合光訊號之傳送示意圖。光通信系統200係包含接收 端主機21、同調光通信模組22、第一光發射機23與 第二光發射機24。 接收端主機2〗係用以發送調制深度控制訊號S ; 同調光通信模組22係用以接收並發送調制深度控制 訊號S至第一光發射機23與第二光發射機24。 第一光發射機23係具有第一調制深度控制模組 231，用以根據調制深度控制訊號S調整第一光發射機 23所發射之第一光訊號L1之第一調制深度；其中， 於本創作之一較佳實施例中，第一調制深度控制模組 可以包含數位可調式衰減器（Digital Variable Attenuator ; DVA)，藉以調整第一光訊號L1之第一調 制深度。 第二光發射機24係具有第二調制深度控制模組 241，用以根據調制深度控制訊號S調整第二光發射機 24所發射之第二光訊號L2之第二調制深度；其中， 於本創作之一較佳實施例中，第二調制深度控制模組 可以包含數位可調式衰減器，藉以調整第二光訊號L2 之第二調制深度。 其中，同調光通信模組22更用以接收第一光訊號 L1與第二光訊號L2，並據以調制並發送混合光訊號L3 至接收端主機21，接收端主機21並據以自混合光訊號 L3有效解析出第一光訊號L1與第二光訊號L2,供接收 端子機25與26接收使用。 6 M398295 此外，於本創作之一較佳實施例中，接收端主機21 可以根據所解析出之第一光訊號L1之第一訊號雜訊比 (Signal-to-noise ratio ; SNR)與第二光訊號 L2 之第二訊 號雜訊比以發送調制深度控制訊號S，由於本創作之主 要精神係在於利用改變光訊號之調制深度以改善光訊 號之訊號雜訊比，因此光通訊系統200僅需要針對所 解析出之光訊號中，訊號雜訊比低於預設之訊號雜訊比 臨界值之光訊號做調制深度的調整即可。 舉例而言’當接收端主機21所解析出之第一光訊 號L1之第一訊號雜訊比低於廠商或使用者預設的訊號 雜訊比臨界值時，接收端主機21即判斷可能有0BI現 象發生的可能，因此即可藉由發送調制深度控制訊號S 來控制第一光發射機23，以增加第一光訊號之第一 調制深度，換以言之即是增加第一光訊說L1之光調製 指數(Optical Modulation Index ; 0MI)，如此一來即可增 加接收端主機21所解析出之第一光訊號乙〗之第一訊號 雜訊比，進而避免0BI現象的發生。 綜合以上所述’相較於習知之光通訊系統1 〇〇，本 創作於第一光發射機23與第二光發射機24分別設置 第一調制深度控制模組231與第二調制深度控制模組 241，並依據接收端主機21所發送之調制深度控制訊 號S改變第一光訊號L1之第一調制深度與第二光訊 號L2之弟一 §周制殊度’因此能夠於遠端即時的改善 訊號雜訊比，並避免0BI現象的發生。 7 M398295 藉由上述之本創作實施例可知，本創作確具產業上 之利用價值。惟以上之實施例說明，僅為本創作之較佳 實施例說明，舉凡所屬技術領域中具有通常知識者當可 依據本創作之上述實施例說明而作其它種種之改良及 變化。然而這些依據本創作實施例所作的種種改良及變 化，當仍屬於本創作之創作精神及界定之專利範圍内。 【圖式簡單說明】 第一圖係為習知技術的光通信系統架構； 第二圖係為接收端主機傳送調制深度控制訊號至第 一光發射機與第二光發射機之示意圖；以及 第三圖係為第一光訊號、第二光訊號與混合光訊號 之傳送示意圖。 【主要元件符號說明】 光通信系統100 光發射機11、12 同調光通信模組13 接收端主機14 接收端子機15、16 光信號 U、L2、L4、L5 混合光信號L3 波長差d 1 光通信系統200 8 M398295 接收端主機21 同調光通信模組22 第一光發射機23 第一調制深度控制模組231 第二光發射機24 第二調制深度控制模組241 接收端子機25、26 調制深度控制訊號S 第一光訊號L1 第二光訊號L2M398295 V. New description: [New technology field] Especially an optical communication system This is a communication system, system 0 [previous technology] * Tree power __ application has become more and more popular in modern times, but In response to the needs of users, TV programs have also become more and more. With the increase in signal transmission and the emergence of two-way interactive services, cable TV networks have evolved toward fiber-to-the-country or fiber-to-the-point. Please refer to the optical communication system architecture of the m-th system. In the "system 1", the transmitting end has optical transmitters n and 12, and respectively for transmitting optical signals L1 and l2 to the Wavelength Division Multiplexing (WDM) module 13, and then, the same dimming communication The module 13 modulates the optical signals L1 and L2 into _mixed optical signals L3 and transmits them to the receiving end host 14 for the receiving end host 14 to demodulate the optical signals L4 and L5 from the mixed optical signal L3, and for receiving the terminal 15 and 16. Receiving. However, when the wavelength difference dl between the optical signals L1 and L2 emitted by the optical transmitters 11 and 12 is less than a certain degree, the optical communication system 100 is caused to have an optical beat interference (OBI). The phenomenon 'has the noise and noise of the optical signals L4 and L5 demodulated by the receiving host 14 , resulting in a lower signal-to-noise ratio (SNR) of the system, which is more likely to cause light in severe cases. Communication system 100 3 M398295 Communication interruption. [New content] The technical problems and objectives to be solved by this creative: Therefore, the main purpose of this creation is to provide an optical communication system that can be transmitted by the receiving host. The depth control signal is used to adjust the modulation depth of the optical signals emitted by the first optical transmitter and the second optical transmitter to improve the signal to noise ratio of the system. The technical means for solving the problem: an optical communication system includes a receiving end host, a same dimming communication module, a first optical transmitter and a second optical transmitter; a receiving end host is configured to transmit a modulation depth control signal; and a same dimming communication module is configured to receive and transmit a modulation depth control signal to a first optical transmitter and a second optical transmitter; the first optical transmitter has a first modulation depth control module, configured to adjust a first modulation depth of the first optical signal emitted by the first optical transmitter; The second optical transmitter has a second modulation depth control module for adjusting a second modulation depth of the second optical signal emitted by the second optical transmitter; wherein the same optical communication module is used for the first optical signal And the second optical signal is modulated into a mixed optical signal and transmitted to the receiving end host for parsing the first optical signal and the second optical signal. In a preferred embodiment of the present invention, the first The depth control module can include a Digital Variable Attenuator (DVA), and the second modulation depth control module can also include a 4 M398295 digitally adjustable attenuator. β is another preferred embodiment of the present invention. The receiving end host may send the modulation depth control signal according to the first signal noise ratio of the first optical signal and the second signal noise ratio of the second optical signal. The creation compares the effects of the prior art: Compared with the conventional optical communication system, the first optical transmission and the second radiojector respectively set the first modulation depth control mode and the second modulation depth control module, and according to the modulation sent by the receiving end host. The depth control signal changes the first modulation depth of the first optical signal and the second modulation depth of the second optical signal, so that the signal noise ratio of the optical communication system can be improved instantaneously at the far end, and the occurrence of artifacts is avoided. The specific embodiments used in the present application will be further illustrated by the following embodiments and drawings. [Embodiment] This creation relates to a communication system, especially an optical communication system. A preferred embodiment is set forth below to illustrate the present teachings, and it is well known to those skilled in the art that this is merely an example and is not intended to limit the creation itself. The contents of this preferred embodiment are detailed below. Please refer to the second figure and the third figure. The second picture is a schematic diagram of the receiving end transmitting the modulation depth control signal to the first optical transmitter and the second optical transmitter. The third picture is the first optical signal and the second picture. Transmission diagram of optical signal and mixed 5 M398295 combined optical signal. The optical communication system 200 includes a receiving end host 21, a coherent optical communication module 22, a first optical transmitter 23, and a second optical transmitter 24. The receiving end host 2 is configured to transmit the modulation depth control signal S; the same optical communication module 22 is configured to receive and transmit the modulated depth control signal S to the first optical transmitter 23 and the second optical transmitter 24. The first optical transmitter 23 has a first modulation depth control module 231 for adjusting the first modulation depth of the first optical signal L1 emitted by the first optical transmitter 23 according to the modulation depth control signal S. In a preferred embodiment, the first modulation depth control module may include a Digital Variable Attenuator (DVA) to adjust the first modulation depth of the first optical signal L1. The second optical transmitter 24 has a second modulation depth control module 241 for adjusting the second modulation depth of the second optical signal L2 emitted by the second optical transmitter 24 according to the modulation depth control signal S. In a preferred embodiment, the second modulation depth control module may include a digitally adjustable attenuator for adjusting the second modulation depth of the second optical signal L2. The dimming communication module 22 is further configured to receive the first optical signal L1 and the second optical signal L2, and modulate and transmit the mixed optical signal L3 to the receiving end host 21, and receive the self-mixing light according to the host 21 The signal L3 effectively resolves the first optical signal L1 and the second optical signal L2 for use by the receiving terminal devices 25 and 26. 6 M398295 In addition, in a preferred embodiment of the present invention, the receiving end host 21 can perform a first signal-to-noise ratio (SNR) and a second according to the first optical signal L1 that is parsed. The second signal noise ratio of the optical signal L2 is to transmit the modulation depth control signal S. Since the main spirit of the present invention is to change the modulation depth of the optical signal to improve the signal noise ratio of the optical signal, the optical communication system 200 only needs to For the resolved optical signal, the signal noise is adjusted according to the optical signal of the preset signal noise ratio threshold. For example, when the first signal noise ratio of the first optical signal L1 parsed by the receiving host 21 is lower than the threshold of the signal noise ratio preset by the manufacturer or the user, the receiving host 21 may determine that there is a possibility. The possibility of the 0BI phenomenon occurs, so that the first optical transmitter 23 can be controlled by transmitting the modulation depth control signal S to increase the first modulation depth of the first optical signal, in other words, to increase the first optical signal. The optical modulation index (0MI) of L1 can increase the first signal noise ratio of the first optical signal B analyzed by the receiving host 21, thereby avoiding the occurrence of the 0BI phenomenon. In combination with the above-mentioned optical communication system 1 , the first modulation depth control module 231 and the second modulation depth control mode are respectively set in the first optical transmitter 23 and the second optical transmitter 24 . The group 241 changes the first modulation depth of the first optical signal L1 and the second optical signal L2 according to the modulation depth control signal S sent by the receiving end host 21, so that it can be instantaneously located at the far end. Improve signal-to-noise ratio and avoid the occurrence of 0BI. 7 M398295 It can be seen from the above-described embodiments of the present invention that the creation has an industrial use value. However, the above embodiments are merely illustrative of the preferred embodiments of the present invention, and those skilled in the art can make various other modifications and changes as may be described in the above embodiments. However, all of the improvements and variations made in accordance with the present embodiment are still within the scope of the creative spirit and definition of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS The first figure is an optical communication system architecture of the prior art; the second picture is a schematic diagram of the receiving end host transmitting a modulation depth control signal to the first optical transmitter and the second optical transmitter; The three pictures are schematic diagrams of the transmission of the first optical signal, the second optical signal and the mixed optical signal. [Main component symbol description] Optical communication system 100 Optical transmitters 11, 12 Same as dimming communication module 13 Receiving end host 14 Receiving terminal machine 15, 16 Optical signals U, L2, L4, L5 Mixed optical signal L3 Wavelength difference d 1 light Communication system 200 8 M398295 receiving end host 21 same dimming communication module 22 first optical transmitter 23 first modulation depth control module 231 second optical transmitter 24 second modulation depth control module 241 receiving terminal machine 25, 26 modulation Depth control signal S first optical signal L1 second optical signal L2