標準號：BS EN 4533-002-2006
中文標準名稱：航空航天系列.纖維光學系統.手冊.試驗和測量
英文標準名稱：Aerospace series - Fibre optic systems - Handbook - Test and measurement
標準類型：V25
發布日期：2006/11/30 12:00:00
實施日期：2006/11/30 12:00:00
中國標準分類號：V25
國際標準分類號：49.060
引用標準：EN 4533-004;ARP5061
適用范圍：Insertion loss is the most frequent measurement performed on a fibre optic link. The avionic system designerwill want to know or predict the insertion loss of a link to determine its performance. Aircraft manufacturers willwant to measure the insertion loss of harness components during assembly and before it is delivered to thecustomer to highlight faults and to provide a record of the performance of the harness at the beginning of itslifetime (footprinting). The insertion loss will be measured at intervals during the lifetime of the aircraft todiscover or identify faults and any gradual degradation in performance of the harness.There is, however, one problem. It is difficult to collect reliable and consistent measurements of the insertionloss on any multi-mode fibre optic harness where the distance between components is relatively small (lessthan 100 metres). The reason is that the insertion loss of a component or a harness depends on the powerdistribution of the light injected into it. This leads to very large differences in the measured value of theinsertion loss [1] depending on the power distribution of the source used to make the measurement.This Part of EN 4533 will explain the measurement problem and the techniques used to overcome them ingreater detail.