Who uses high frequency radars?

High-frequency radar (HFR) is a unique technology mapping ocean surface currents and wave fields (along with other variables) over wide areas with high spatial and temporal resolution. HFR is cost-effective, requiring only small manpower and technical costs.

The choice of frequency depends on the application requirements . The minimum antenna size is proportional to wavelength and inversely proportional to frequency. Airborne applications often are limited in the size of antenna that can be used. A smaller antenna dictates a higher frequency and lower wavelength choice.

Measuring ranges Low frequency signals have a longer wave length and will travel farther than higher frequencies . Radar transmitters with high frequency emitters are capable of measuring ranges of approximately 100 feet, which is okay for most applications.

Radar is an “active” sensing device in that it has its own source of illumination (a transmitter) for locating targets. It typically operates in the microwave region of the electromagnetic spectrum—measured in hertz (cycles per second), at frequencies extending from about 400 megahertz (MHz) to 40 gigahertz (GHz) .

The best frequency to use for a radar depends upon its application. Like most other radio design decisions, the choice of frequency usually involves tradeoffs among several factors such as physical size, transmitted power, antenna beamwidth, and atmospheric attenuation .