Kõrgsageduselisi

Kõrgsageduselisi is the partitive plural of the Estonian adjective kõrgsageduslik and is used to describe plural nouns that relate to high frequency. In Estonian, adjectives agree with the noun in case and number, so kõrgsageduselisi appears in phrases such as kõrgsageduselisi seadmeid (high‑frequency devices) or kõrgsageduselisi signaale (high‑frequency signals). The form itself denotes the characteristic of the referenced items rather than a standalone concept.

In technical usage, kõrgsagedus refers to electromagnetic phenomena or systems operating at relatively high frequencies compared with audio or low-frequency domains. Exact bounds vary by field, but high frequency generally spans from the kilohertz to the gigahertz range. In radio engineering, the HF band is commonly defined as about 3–30 MHz, while other applications may treat tens of kilohertz up to several gigahertz as high frequency or microwave.

Applications of high‑frequency phenomena and devices include telecommunications, radio and television transmission, radar, and microwave technology, as well as medical and scientific instrumentation. Devices operating at high frequency require design considerations such as impedance matching, shielding, and attention to electromagnetic compatibility and safety standards for exposure to electromagnetic fields.

In Estonian-language contexts, kõrgsageduselisi is primarily a grammatical form used to describe high‑frequency items, rather than a distinct technical category on its own.