Before revision: An Active Design allows the construction of antennas of limited size and / or wide frequency range, and are primarily used in situations where a simpler and more receptive large antenna is either impractical (inside a portable radio) or impossible (suburban residential area that disallows use of large outdoor low-frequency antennas).
After revision: An active design allows the construction of antennas of limited size and / or wide frequency range, and are primarily used in situations where a simpler and more receptive large antenna is either impractical (inside a portable radio) or impossible (suburban residential area that disallows use of large outdoor low-frequency antennas).