Assertion: antenna's radiation resistance | /r/HasProperty | low
Facets:
value: very
type: DEGREE
value: usually
type: DEGREE
Source sentences:
text: It can be seen that, since the radiation resistance is usually very low, the major design problem is to keep the other resistances in the antenna-ground system low to obtain the highest efficiency.
text: The radiation resistance of antennas (the resistance that represents power radiated as radio waves) drops as their length becomes small compared to a wavelength, so the radiation resistance of antennas on the LF and VLF bands is very low, often as low as one ohm or less.
text: These antennas have low radiation resistance and high reactance, so that their impedance is difficult to match to a transmitter.
text: The radiation resistance of short antennas can be very low, as low a few ohms in the LF or VLF bands, where antennas are commonly short and inductive loading is most needed.
text: It can be seen that, since the radiation resistance is usually very low, the major design problem is to keep the other resistances in the antenna-ground system low to obtain the highest efficiency.
text: At medium and low frequencies, the high antenna capacitance and the high inductance of the loading coil, compared to the short antenna’s low radiation resistance, makes the loaded antenna behave like a high Q tuned circuit, with a narrow bandwidth over which it will remain well matched to the transmission line, when compared to a 1/4 λ monopole.
text: At medium and low frequencies, the high antenna capacitance and the high inductance of the loading coil, compared to the short antenna’s low radiation resistance, makes the loaded antenna behave like a high Q tuned circuit, with a narrow bandwidth over which it will remain well matched to the transmission line, when compared to a 1/4 λ monopole.
text: So at low frequencies even a T-antenna can have very low radiation resistance, often less than 1 ohm, so the efficiency is limited by other resistances in the antenna and the ground system.
text: So at low frequencies even a T-antenna can have very low radiation resistance, often less than 1 ohm, so the efficiency is limited by other resistances in the antenna and the ground system.