Assertion: radar's antenna | /r/HasProperty | required
Facets:
value: often
type: DEGREE
Source sentences:
text: Since the signal going to the target and returning had a propagation loss proportional to the range raised to the fourth power, a powerful transmitter and large antennas were required.
text: Since Synthetic Aperture Radar (SAR) is much lower in frequency than optical systems, even moderate Synthetic Aperture Radar (SAR) resolutions require an antenna too large to be practically carried by an airborne platform: antenna lengths several hundred meters long are often required.
text: To produce a 1-degree beam at the most common frequencies, an antenna 1.5 kilometres (0.93 mi) wide is required.