Doped fiber amplifier (The typical representative: EDFA) Erbium-doped fiber amplifier (EDFA) is the most widely used fiber-optic amplifiers, mainly made of Erbium-doped fiber (EDF), pump light source, optical couplers, optical isolators, optical filters and other components.
Noun. 1. national income-the total value of all income in a nation (wages and profits and interest and rents and pension payments) during a given period (usually 1 yr).
A variety of measures of national income and output are used in economics to estimate total economic activity in a country or region, including gross domestic product (GDP), gross national product (GNP), net national income (NNI), and adjusted national income (NNI* adjusted for natural resource depletion).n order to count a good or service, it is necessary to assign value to it. The value that the measures of national income and output assign to a good or service is its market value â the price it fetches when bought or sold.