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).
U.S. investment income means income from investments in the United States in stocks, bonds, or other domestic securities, financial instruments held in the execution of governmental financial or monetary policy, and interest on money deposited by a foreign government in banks in the United States.