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).
The most important national account is the gross domestic product. Gross domestic product (GDP) is the total market value of all final goods and services produced in a given year within the United States, whether produced by citizens, companies, or by foreigners in the United States.he most important national account is the gross domestic product. Gross domestic product (GDP) is the total market value of all final goods and services produced in a given year within the United States, whether produced by citizens, companies, or by foreigners in the United States.