200831872 九、發明說明： 【發明所屬之技術領域】 纖斷 點查=難細繼的繊 查找方法’制是有種透過對光 【先前技術】 在以光纖傳縣學«的线巾，為能確録錢接的品質，減少 故障因素’或者在故障日賴出光_故障點，—網需要對先纖進行檢 測。檢測方法很多，主要分為人工簡易測量和精密儀器測量。人工簡易 測量-般麟快速檢測光_通斷和敎咖來分趣選光纖束中的 特疋光纖，其原理係個-光源從光纖的—端發射可見光，再自光纖的 另-‘觀察光纖之發光與否來進行判斷。這種方法雖然冑便胃行，但無 法對於光纖内光信號的衰減做定量測量，同時也無法判斷光纖中斷點的 位置。至於精松儀器測篁’通常是使用光功率計或光時域反射儀(〇ptical Time Domain Reflectometer，0TDR)對光纖進行定量測量，可測出光纖内 的信號衰減量和接頭處的衰減量，亦可用以測量出光纖中斷點位置。這 種測量可用來定量分析光纖網路出現故障的原因和對光纖網路產品進 行評估。 另一種已知的量測方法則為背向散射法，其是一種沿光纖長度上測 量衰減的方法。當光束沿光纖傳播時，由於光纖本身折射率的細微不均 勻之故，光纖會不斷地產生瑞利散射，部分散射光會反向傳播回到輸入 端。換言之，雖然在正常使用的光纖中，光功率絕大部分是前向傳播， 自輸入端傳播至輸出端，但亦有少部分的光功率會朝向輸入端做背向散 射傳播。因此，將雷射光射入至光纖内，並監測光纖内所產生的背向散 射光的強度變化，即可以得到沿光纖長度分佈的衰減曲線。這項技術可 以用來探測光纖中的散射係數、損耗及連接點、耦合點、中斷點等的情 200831872 光纖中可以測量到的背向散射光有兩種，一種是瑞利散射光，另一 種是光纖斷面或光纖連接處產生的菲涅爾反射。光時域反射儀的量測原 理是基於光的背向散射與菲涅耳反射原理，利用光在光纖中傳播時產生 的背向散射光來獲取衰減的資訊。因此藉由在光入射處利用分光器監測 背向散射的時間曲線，其不僅可以測量接入光纖的長度和衰減，亦能偵 測出局部的不規則性、中斷點及在接頭和連接器引起的光功率損耗。、 就光纖斷點的查找而言，由於光纖斷點處對於沿著光纖傳播的光信 號所產生的反射信號是遠大於斷點之正常光纖内壁所反射者，因此利用 光時域反射儀來監測此較大之反射信號被接收到的時間，再配合光速之 # 固定數值，即可推算出光纖的斷點位置。附圖中的第一圖示意地顯示出 此種光纖斷點查找的實施方式，而第二圖中則顯示出此已知方法查找光 纖斷點時所可能得到的光反射量分佈圖的典型範例。 但是使用光時域反射儀來债測光纖斷點位置時，會產生一些困擾。 例如’如第二圖中所示，由於光信號在光纖中會距離增加而加大損耗， 因此光纖中的光反射量會隨著距光入射處之距離的增加而遞減，故在此 種應用下，近距離處的反射量會較大，而遠處的反射量則減小，所以近 距離處的光纖内壁的正常反射量極有可能會大於自遠端斷點處反射回 來的光信號，致使所接收到的最大反射信號不一定是來自光纖的斷點， 因之會使得對於光纖斷點位置的推算及判斷產生錯誤。 因此有必要提供一種準確性更高的光纖斷點查找方法，以解決習知 技術所存在的缺陷。 【發明内容】 本發明之目的在於提供一種光纖斷點查找方法，可以更精確地判定 光纖斷點的位置。 本發明之另一目的在於提供一種補償光纖斷點反射信號之方法，以 供更精確地判定光纖斷點的位置。 6 200831872 根據本發明之一實施例，其提供一種補償光纖斷點反射信號的方 法，其包含有發射多輪的脈衝信號，每一輪中發射固定或不定數量的脈 衝信號至一欲查找斷點的光纖内，並接收自光纖反射回來的信號，再利 用多個不同電壓的高壓調製信驗賴從光纖反射回來的反射信號重 覆進行多次調制、放大及採樣，以降低當斷點位置較遠時反射信號強度 減弱而造成對斷點位置誤判斷的情形。 根據本發明的另一觀點，其根據對於光信號在光纖中傳輸所產生之 損耗里的實測數據，提供一損耗量補償計算式，並利用該計算式計算出 母一實測反射信號的相對應補償反射信號。藉由如此補償過的反射信 號，其可以放大反射信號，並根據強度較強之異常反射信號來判斷及推 算光纖斷點的位置。 以下將配合圖式，針對本發明的實施例來說明本發明的原理及應 用。 【實施方式】 參閱弟二圖，其中顯示出可應用在本發明中來實施本發明光纖斷點 查找方法的光纖斷點定位儀，其在此說明中係以編號u加以標示。根 據本發明，此光纖斷點定位儀11可以是一種已知的雷射測距儀，其中 包含有信號發射電路20，具有一雷射二極體（LD) 22，可發射出一雷 射脈衝信號24。在實施本發明之方法時，係將此雷射脈衝信號22射入 欲查找斷點的光纖12 (見第四圖）内。此光纖斷點定位儀u另外包含 有一信號接收電路26，其具有一光電二極體（APD) 28，可用以接收 由該光纖12内目標物（在此案中即為光纖的斷點）反射回來的反射信 號30。信號接收電路26接收並處理反射信號30後，傳送一相對應^ 電4號32至一採樣電路34中進行採樣，並進一步透過資料處理f元 36進行資料的處理，以取得反射信號30取得之時間與脈衝信號22之 發射時間的差值，並藉此及光速的固定值來計算出該光纖内之標物 距離。 、 本發明係將傳統的雷射測距儀應用到光纖斷點的查找作業中，以判 200831872 定光纖斷點的位置。第四圖中示意地顯示出本發明之光纖斷定查找方法 的操作原理。如前所述，用以實施本發明之光纖斷查找方法的光纖斷點 定位儀11包含有光信號的發射電路20及接收電路26、採樣電路34、 以及資料處理單元36等，其可透過信號發射電路2〇的雷射二極體22 發射一雷射脈衝信號至欲查找斷點的光纖12内。當光信號在光纖12内 傳輸時，傳輸過程中光會發生反射，而當遇到斷點時，斷點處更會發生 異常反射，即反射量突然增大，隨即又迅速回落，如第二圖中標號4〇 處所示。當反射光由光纖斷點定位儀η的信號接收電路26透過光電二 極體28純接收並轉換為魏錢後，透過對魏氣錢進行處理， 可以得知錢發射及接收_時縣，_可以縛出光纖斷點距離光 纖斷點定位儀之距離，即可得到光纖斷點的位置。 惟如則所述’除了光纖斷點處以外，正常的光纖内壁亦會對於光信 號產生反射的侧，且此反射號會隨著距_衰減，因此在判定光纖^ 點上常會受到影響，造成誤判。根據本發明，其提供一種補償方法，用 以針對自光纖内反射回來的光信號加錢行補償，以修正因距離所致之 誤判。根據本發明之-實施例，利用數個不同電位的高壓信號依序對從 光纖反翻來的反射錢紐進行多次·、放大及採樣，崎低當斷 點位置距離定位儀較糾反射錢強度減弱賴齡置觸的影響。 以下針對本發明之此觀點的方法，以一實例來說明本發明斷點反 信號之補償方法。 首先，第-輪連續發射複數個（第一數量）發射脈衝信號，在 明中該第-數量是以二十（2〇)為例，但亦可為其他適合的數量。該二 十個發射脈衝健可以採肋同或不同_率及振幅（或位 接收先後被光纖反射回來的二十個（第一數量）反射信號。針對此^ 個反射信號之每-者具有第—電壓之第—調製信號進行^ 製’進而放大-預定的第—倍率如果該第—電壓踊高的話，則此時 來自光纖近處反射_㈣會麵飽和織，而來自相 對較弱的信號被放大-収例，但不會達職和。另—方面，光 200831872 ===:=:_:的放大狀態。對該二十 將各採樣點上點採到高電壓位準 電壓位準而）及低電壓位準，分別以高及低邏輯位準（即“i，，斑‘‘〇>，，考 代表之，並將此種數位資料儲存於資料庫中。 、 在前述的第-輪發射脈衝信號後，每_採樣點均會具有第一 (在此為二十個）的高低邏輯位準數據。 接收it第==歸複數個（第二數量）發射脈衝信號’同時並 =該^^1敝射錢。鱗二數討辦目_ ===量是採取與第-數量娜 ，射信號，採用-具有第二電壓之第二調製信號來對‘匕 间壓，製’進而將該等反射信號別放大一預定的第二倍率。在此^第 二電壓係低於於前述的第_電壓，故第二放大倍率會小於第一放= 率。在此情形下，來自比近處_處的反射信號在帛二倍=大後已^ 飽:僅;相同的’遠處的信號仍然會被 大小而疋，光纖斷點處的反射信號有可能仍 ^ 信號儲存於該資料庫中。 ™專第-輪的南低邏軏 不斷重復上述魏、接收、調製、放大、採樣、記錄等作 或多輪，即依序下來為第三輪、第四輪、...等）。Ί :輪，用的調製信號的電壓是依次低於前_輪所使用者 電 壓、第四電壓、...妓依序降低其鱗，而其降低之量並不―定要第j 電壓與第二電壓間的差值並不一定要等於第二第二電 非均勻遞減 >但亦可具有峡的綠（均勻 母一輪發射的脈衝信號數量（即第三數量、第四數量、…等）並不一卜定 200831872 要^可選擇在每一輪中均發射相同數量的脈衝信號（如前述的 -固脈衝信號）。另外，重覆的輪數可視具體情況而定，例如說十次。 經過則述的操作後，每一採樣點均會具有相等於“輪數，，乘以“ ^脈，域數K (在“發概衝健數量”献值的情形，即前述第 务數里第一數里、第二數量、…等相同的情形〕的高低邏輯位準數據， 若以發射十輪的脈衝信號，每—輪發射二十個脈衝錢，則每_採樣點 均會^ 200 (=1〇χ20)個“〇，，或丫的邏輯數據。在每一輪之“發射 ft衝信號㈣”不较__巾，每_雜闕邏概躺數量^ 母一輪之“發射脈衝信號數量，，的加總。 根據本發明，每一採樣點的邏輯數據均加以加總起來，而其加總的 最大值即為所有“發射脈衝信號數量，，的總和，因為可以想見的， 每一採樣點在每一次脈衝信號發射時所反射之信號中所可得到的邏輯 非二即1，而若每一次均為丨，則總和最大值即為脈衝信號發射之次數。 在前述之發射十輪，每一輪二十個脈衝信號的例子中，任一採樣點所可 得到的最大數值為200。 ‘ 另外，可以瞭解的，該等邏輯數據的加總可以在每一次採樣後即加 以加總，也可以在最後再一次加總，惟後者會需要佔用較多的記憶體來 儲存相關的數據。 由於遠處的反射信號相對較弱，因此即使採用較低電壓來進行高壓 調製仍有可能被放大，所以斷點處的採樣邏輯數據的總和會相對變大， 使其判斷較不易產生錯誤。因此，在前述的基礎下，本發明的補償方法 可以讓一般判斷斷點位置的方法更加精準。換言之，可以設定一參考 值，例如說120 (針對前述最大數值2〇〇的例子），當遠處採樣點的總 和邏輯數據大於此參考值則可判定為一光纖斷點。 雖然反射信號的採樣是以預定頻率進行的，因此每一採樣點代表一 時間點。又，由於光速係定值，因此時間點與光纖距離脈衝發射處（即 第四圖中的光纖斷點定位儀11)具有正比例關係，可以自光纖斷點的 相對應採樣點推算出該斷點在光纖上的實際位置。 200831872 藉由前述的操作，可以使得近處的強信號在較高電壓調製的時候因 為飽和而不能被放大，而遠處的弱信號則因尚未達到飽和而每一輪都被 ，從而可以補償遠處反射信號（以及位在遠處之光纖斷點處的反射 信號）因為距離長而產生衰減的赫，進而可使簡點關斷更為正 確。換言之，依t述方法所得到的反射信號或其相對應的總和邏輯數據 即可配合於習用之光纖查找方法中來判斷光纖斷點位置。亦即透過較強 的反射或是較大的總和邏輯數據來判定光纖斷點。 由於近距離處的反射信號會較強，因此即使近距離處沒有斷點，口 是正常的先_壁所造颜反射，在放域亦有可能成為飽和。因此ς 故，必須藉由逐步降低高_製_電壓位準，使縣_輪的放大倍率 ，步降低’簡鱗-次放大均使得近距_反射舰成為飽和，導致 一根據本發明的另一觀點，其提供$ 一種的補償方法，其中先針對光 信號在光纖巾傳輸時的損耗量財測方法取得。例如將波長為155〇腿 =光束在單模賴巾進行賴，並繼其單錄度賴耗量。在此例 中’所測得的損耗量為〇.2db/km。 旦^^測得的損耗量，透過一補償計算式進行與距離有關的光損粍 里的補正’魏消輯對於光信麵度所造成的損耗。該計算式如200831872 IX. Description of the invention: [Technical field to which the invention belongs] Fiber-cutting point check=Difficult to follow the 繊 方法 方法 ' ' ' ' ' ' 【 【 【 【 【 【 【 【 【 【 【 【 【 【 【 【 【 【 【 【 【 【 【 【 【 【 It is true that the quality of the money is recorded, and the failure factor is reduced' or the fault occurs on the fault day. The network needs to detect the fiber. There are many detection methods, which are mainly divided into manual simple measurement and precision instrument measurement. Manual and simple measurement - the basic detection of light by _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Whether it is illuminated or not. Although this method is easy to measure the attenuation of the optical signal in the fiber, it is impossible to determine the position of the fiber break point. As for the precision instrumentation, the optical fiber is usually quantitatively measured using an optical power meter or a 时ptical Time Domain Reflectometer (0TDR) to measure the amount of signal attenuation in the fiber and the amount of attenuation at the joint. It can also be used to measure the position of the fiber break point. This measurement can be used to quantify the cause of fiber network failures and to evaluate fiber-optic network products. Another known measurement method is the backscatter method, which is a method of measuring attenuation along the length of the fiber. When the beam propagates along the fiber, the fiber will continuously produce Rayleigh scattering due to the slight unevenness of the refractive index of the fiber itself, and some of the scattered light will propagate back to the input end. In other words, although in the normally used fiber, most of the optical power is forward propagating, from the input end to the output end, there is also a small amount of optical power that is transmitted toward the input end to the backscatter. Therefore, by injecting laser light into the fiber and monitoring the intensity variation of the backscattered light generated in the fiber, an attenuation curve along the length of the fiber can be obtained. This technology can be used to detect the scattering coefficient, loss and connection points, coupling points, breakpoints, etc. in the fiber. There are two kinds of backscattered light that can be measured in the 200831872 fiber. One is Rayleigh scattered light, the other is Rayleigh scattered light. It is the Fresnel reflection produced by the fiber section or fiber connection. The measurement principle of the optical time domain reflectometer is based on the backscattering of light and the Fresnel reflection principle, and the backscattered light generated by the propagation of light in the optical fiber is used to obtain the attenuation information. Therefore, by using the spectroscope to monitor the time curve of backscattering at the incident of light, it can not only measure the length and attenuation of the access fiber, but also detect local irregularities, breakpoints and joints and connectors. Optical power loss. In the search for the fiber breakpoint, since the reflected signal generated by the optical signal transmitted along the optical fiber at the breakpoint of the fiber is reflected by the inner wall of the normal fiber far beyond the breakpoint, the optical time domain reflectometer is used for monitoring. The time at which this larger reflected signal is received, combined with the fixed value of the speed of light, can be used to derive the breakpoint position of the fiber. The first figure in the drawing schematically shows an embodiment of such a fiber breakpoint search, and the second figure shows a typical example of a light reflection amount distribution map that can be obtained by the known method for finding a fiber breakpoint. . However, there are some problems when using an optical time domain reflectometer to measure the fiber breakpoint position. For example, as shown in the second figure, since the optical signal increases the distance in the optical fiber and increases the loss, the amount of light reflection in the optical fiber decreases as the distance from the incident of the light increases, so in this application Underneath, the amount of reflection at a close distance will be larger, and the amount of reflection at a distance will be reduced, so the normal reflection amount of the inner wall of the fiber at a close distance is likely to be larger than the light signal reflected from the distal break point. The maximum reflected signal received is not necessarily the breakpoint from the fiber, which may cause errors in the calculation and judgment of the breakpoint position of the fiber. Therefore, it is necessary to provide a more accurate fiber breakpoint finding method to solve the defects of the prior art. SUMMARY OF THE INVENTION It is an object of the present invention to provide a fiber breakpoint finding method that can more accurately determine the position of a fiber breakpoint. Another object of the present invention is to provide a method of compensating for a fiber breakpoint reflection signal for more accurately determining the position of a fiber breakpoint. 6 200831872 According to an embodiment of the present invention, there is provided a method for compensating a fiber breakpoint reflection signal, comprising: transmitting a plurality of rounds of pulse signals, each of which transmits a fixed or indefinite number of pulse signals to a breakpoint to be found Inside the fiber, and receiving the signal reflected from the fiber, and then using a plurality of high voltage modulation signals of different voltages to repeatedly reflect, amplify and sample the reflected signal reflected from the fiber to reduce the position of the breakpoint When the intensity of the reflected signal is weakened, the position of the breakpoint is misjudged. According to another aspect of the present invention, a loss calculation formula is provided based on the measured data in the loss generated by the optical signal transmitted in the optical fiber, and the corresponding compensation of the mother-measurement reflected signal is calculated by using the calculation formula. Reflected signal. With the thus compensated reflected signal, it is possible to amplify the reflected signal and determine and estimate the position of the fiber breakpoint based on the intensity of the abnormally reflected signal. The principles and applications of the present invention are described with respect to the embodiments of the present invention in conjunction with the drawings. [Embodiment] Referring to the second drawing, there is shown a fiber breakpoint locator which can be applied to the present invention to implement the fiber breakpoint finding method of the present invention, which is indicated by the number u in the description. According to the present invention, the fiber breakpoint locator 11 can be a known laser range finder including a signal transmitting circuit 20 having a laser diode (LD) 22 for emitting a laser pulse. Signal 24. In carrying out the method of the present invention, this laser pulse signal 22 is injected into the fiber 12 (see Figure 4) where the breakpoint is to be sought. The fiber breakpoint locator u additionally includes a signal receiving circuit 26 having a photodiode (APD) 28 that is operable to receive a reflection from a target within the fiber 12 (in this case, a breakpoint of the fiber) The reflected signal 30 is coming back. After receiving and processing the reflected signal 30, the signal receiving circuit 26 transmits a corresponding signal No. 4 to a sampling circuit 34 for sampling, and further processes the data through the data processing f element 36 to obtain the reflected signal 30. The difference between the time and the emission time of the pulse signal 22, and thereby the fixed value of the speed of light, is used to calculate the target distance within the fiber. In the present invention, the conventional laser range finder is applied to the search operation of the fiber breakpoint to determine the position of the fiber breakpoint of 200831872. The operation of the fiber break determination method of the present invention is schematically shown in the fourth figure. As described above, the optical fiber breakpoint locator 11 for implementing the optical fiber break finding method of the present invention includes a transmitting circuit 20 and a receiving circuit 26, a sampling circuit 34, a data processing unit 36, and the like having optical signals, which are permeable to signals. The laser diode 22 of the transmitting circuit 2 emits a laser pulse signal into the optical fiber 12 where the breakpoint is to be found. When the optical signal is transmitted in the optical fiber 12, the light will be reflected during the transmission, and when the breakpoint is encountered, the abnormal reflection occurs at the breakpoint, that is, the amount of reflection suddenly increases, and then quickly falls back, such as the second. The figure is shown at 4〇. When the reflected light is purely received by the signal receiving circuit 26 of the fiber breakpoint locator η through the photodiode 28 and converted into Wei Qian, after processing the Wei Qi Qian, it is possible to know the money transmission and reception _ Shi County, _ The position of the fiber breakpoint can be obtained by binding the distance between the fiber breakpoint and the fiber breakpoint locator. However, if the 'in addition to the fiber breakpoint, the normal fiber inner wall will also reflect the side of the optical signal, and the reflection number will be attenuated with the distance _, so it is often affected in determining the fiber point, resulting in Misjudgment. According to the present invention, there is provided a compensation method for adding compensation for light signals reflected from an optical fiber to correct misjudgment due to distance. According to the embodiment of the present invention, a plurality of high-voltage signals of different potentials are used to sequentially perform multiple times, amplification, and sampling on the reflected coins that are reversed from the optical fiber, and the position of the breakpoint is more reflexive. The intensity is weakened by the influence of the ageing. The method for compensating the breakpoint inverse signal of the present invention will be described below by way of an example for the method of the present invention. First, the first round continuously transmits a plurality of (first number) transmitted pulse signals. In the description, the first-number is twenty (2 〇), but may be other suitable quantities. The twenty transmit pulses can be ribbed with the same or different _ rate and amplitude (or the bit receives the twenty (first number) reflected signals that are reflected back by the fiber. For each of the ^ reflected signals has the first - the first of the voltage - the modulation signal is carried out 'and then amplified - the predetermined first - magnification. If the first - voltage is high, then the near reflection from the fiber _ (four) meets the surface of the saturated weave, and from the relatively weak signal Being magnified - received, but not up to the job. On the other hand, the light 200831872 ===:=:_: the amplification state. For the twenty points, the sampling points are taken to the high voltage level voltage level. And) and the low voltage level, respectively, with high and low logic levels (ie "i,, spot ''〇>, which is represented by the test, and stores such digital data in the database. After the first round transmits the pulse signal, each _ sampling point will have the first (here twenty) high and low logic level data. Receive it === return multiple (second number) transmit pulse signal' And = ^ ^ 1 敝 shot money. Scale two to discuss the _ = = = amount is taken with the number - number Na Transmitting a signal by using a second modulated signal having a second voltage to amplify the reflected signal by a predetermined second magnification. The second voltage is lower than the foregoing The _ voltage, so the second magnification will be less than the first release rate. In this case, the reflected signal from the near _ is twice as large as 大 = full; only; the same 'distance' The signal will still be sized and smashed, and the reflected signal at the fiber breakpoint may still be stored in the database. The south-low logic of the TM-rounder repeats the above-mentioned Wei, receive, modulation, amplification, sampling, Record the same or multiple rounds, that is, the third round, the fourth round, ..., etc.). Ί: The voltage of the modulated signal used is lower than the voltage of the user of the previous _ wheel, and the fourth The voltage, ... 妓 sequentially reduces its scale, and the amount of reduction does not mean that the difference between the jth voltage and the second voltage does not necessarily have to be equal to the second second electrically non-uniform decrease> Can have the green of the gorge (the number of pulse signals emitted by the uniform mother one round (ie the third quantity, the fourth quantity, ... It is not certain that 200831872 can choose to transmit the same number of pulse signals (such as the aforementioned - solid pulse signal) in each round. In addition, the number of repeated rounds can be determined according to the specific situation, for example, ten times. After the operation described above, each sampling point will have the same number of rounds, multiplied by the number of ^ pulses, and the number of domains K (in the case of the number of "generalized impulses", that is, in the aforementioned number of transactions The high and low logic level data of the first case, the second quantity, ..., etc., if the pulse signal of ten rounds is transmitted, and each pulse emits 20 pulse money, each _ sample point will be ^ 200 (=1〇χ20) "逻辑,, or 丫 logical data. In each round, "transmit ft rush signal (four)" is not more than __ towel, each _ 阙 阙 概 ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ The sum of the quantities, and. According to the present invention, the logical data of each sampling point is summed up, and the summed maximum value is the sum of all the "number of transmitted pulse signals," because it is conceivable that each sampling point is at each time. The logic obtained in the signal reflected by the pulse signal is not two, and if each time is 丨, the maximum value is the number of times the pulse signal is transmitted. In the above ten rounds, each round twenty In the example of a pulse signal, the maximum value that can be obtained at any sampling point is 200. ' In addition, it can be understood that the sum of the logical data can be added after each sampling, or at the end. Once added, the latter will need to use more memory to store the relevant data. Since the reflected signal in the far side is relatively weak, even if the lower voltage is used for high voltage modulation, it may be amplified, so the breakpoint is The sum of the sampling logic data will be relatively large, making it less likely to cause errors. Therefore, based on the foregoing, the compensation method of the present invention can make a general judgment. The method of point position is more precise. In other words, a reference value can be set, for example, 120 (for the above-mentioned maximum value 2〇〇 example), when the sum of the logical data of the distant sampling point is larger than the reference value, it can be determined as a fiber break. Although the sampling of the reflected signal is performed at a predetermined frequency, each sampling point represents a time point. Also, since the speed of light is fixed, the time point is separated from the fiber by the pulse emission (ie, the fiber in the fourth figure is broken). The point locator 11) has a proportional relationship, and can calculate the actual position of the breakpoint on the optical fiber from the corresponding sampling point of the fiber breakpoint. 200831872 By the foregoing operation, the strong signal in the vicinity can be modulated at a higher voltage. When it is saturated, it cannot be amplified, and the weak signal in the distance is not saturated yet and is rounded every turn, so that it can compensate for the distant reflected signal (and the reflected signal at the far-end fiber break point) because of the distance. Long and attenuated Hz, which in turn makes the simple point turn off more correct. In other words, the reflected signal obtained by the method described or its corresponding And the logical data can be used in the conventional fiber search method to determine the fiber breakpoint position, that is, the fiber breakpoint is determined by strong reflection or larger summed logic data. Strong, so even if there is no break point at a close distance, the mouth is normal. The wall reflection is likely to become saturated. Therefore, it is necessary to gradually lower the high _ voltage level. Magnification of the county_wheel, step reduction 'simplified scale-sub-amplification makes the close-range reflector become saturated, resulting in a compensation method according to another aspect of the invention, wherein the optical signal is first applied to the optical fiber The loss measurement method of the towel transmission is obtained. For example, the wavelength is 155 = leg = the beam is traversed in the single-mode sling, and the singularity is used. In this example, the measured loss is 〇.2db/km. The amount of loss measured by ^^^, through a compensation calculation formula, the distance-related optical loss 补 correction 'Wei Xiaoji's loss to the optical surface. The calculation formula is as
Yl=Yxl〇(Dx0·4) Y代表實際爾的反概，D融公里鱗㈣距離，γ1為 乘以G·4的理由在於’根據前述實測的數據， I母經過—公里的距離就會有G.2db的損耗量，而反射 。賴w二際2的距離的來回各—趟的二倍距離，因此就每一 先纖長度而s，反射信號的損耗量是二倍，即α2χ2=〇.4。 费因種方法，可以利用計算式輕易而迅速地補償反射信 &先纖長度所以成之損耗及衰減，因此在以補償後之反射信號進行光 200831872 纖斷點的觸時，會比技藝中麵行補償之 方式，更能得到精確的 《上所述，本發明確已符合發明專 ^惟，以上所述者奴本發明之較佳實施方式，舉2J；申 利it本㈣之精神所作之纽料或變化，料蓋於後社申 判斷結果 L··^ 【圖式簡單說明】 第一圖係光信號在具有斷點的光纖中傳輸的示意圖。 、第二圖是第一圖中光信號反射量分佈曲線示意圖，其中並顯示出光 纖斷點處的異常反射狀。 第三圖是本發明用來查找光纖斷點之光纖斷點定位儀的示意圖。 第四圖係本發明之一實施例的光纖斷點查找方法之原理圖 【主要元件符號說明】 11 光纖斷點定位儀 12 光纖 2〇 信號發射電路 22 雷射二極體 24 雷射脈衝信號 26 信號接收電路 28 τ ^ 光電二極體 30 反射信號 32 電信號 34 採樣電路 36 — 資料處理單元 40 異常反射信號 12Yl=Yxl〇(Dx0·4) Y represents the inverse of the actual er, D is the distance of the kilometer (four), and the reason why γ1 is multiplied by G·4 is that 'based on the above measured data, the distance of the mother-meter-mile will be There is a loss of G.2db, and reflection. The distance between the distances of the two distances is twice the distance between the two, so for each fiber length, the amount of loss of the reflected signal is twice, that is, α2χ2=〇.4. Due to the method of the fee, the calculation method can be used to easily and quickly compensate the loss and attenuation of the reflection signal & the length of the fiber, so that the light of the 200831872 fiber break point can be compared with the technique in the compensated signal. The method of face compensation can be more accurately obtained. As described above, the present invention has indeed met the invention, and the preferred embodiment of the invention described above is 2J; the spirit of Shenliit (4) The material or change, the material is covered in the post-Social judgment result L··^ [Simple description of the figure] The first picture is a schematic diagram of the optical signal transmitted in the optical fiber with breakpoint. The second figure is a schematic diagram of the light signal reflection amount distribution curve in the first figure, and shows an abnormal reflection shape at the fiber break point. The third figure is a schematic diagram of a fiber breakpoint locator used to find fiber breakpoints in accordance with the present invention. The fourth figure is a schematic diagram of a fiber breakpoint searching method according to an embodiment of the present invention. [Main component symbol description] 11 Fiber breakpoint locator 12 Fiber 2 〇 signal transmitting circuit 22 Laser diode 24 Laser pulse signal 26 Signal receiving circuit 28 τ ^ Photodiode 30 Reflected signal 32 Electrical signal 34 Sampling circuit 36 - Data processing unit 40 Abnormal reflected signal 12