frecvență wikipedia - EAS
Frequency response - Wikipedia
https://en.wikipedia.org/wiki/Frequency_responseWebIn signal processing and electronics, the frequency response of a system is the quantitative measure of the magnitude and phase of the output as a function of input frequency. The frequency response is widely used in the design and analysis of systems, such as audio and control systems, where they simplify mathematical analysis by …
VHF omnidirectional range - Wikipedia
https://en.wikipedia.org/wiki/VHF_omnidirectional_rangeWebVery high frequency omni-directional range (VOR) is a type of short-range radio navigation system for aircraft, enabling aircraft with a receiving unit to determine its position and stay on course by receiving radio signals transmitted by a network of fixed ground radio beacons.It uses frequencies in the very high frequency (VHF) band from 108.00 to 117.95 MHz.
Parking sensor - Wikipedia
https://en.wikipedia.org/wiki/Parking_sensorWebThese systems feature ultrasonic proximity detectors to measure the distances to nearby objects via sensors located in the front and/or rear bumper fascias or visually minimized within adjacent grills or recesses.. The sensors emit acoustic pulses, with a control unit measuring the return interval of each reflected signal and calculating object distances.
Orthogonal frequency-division multiple access - Wikipedia
https://en.wikipedia.org/wiki/Orthogonal_frequency-division_multiple_accessWebOrthogonal frequency-division multiple access (OFDMA) is a multi-user version of the popular orthogonal frequency-division multiplexing (OFDM) digital modulation scheme. Multiple access is achieved in OFDMA by assigning subsets of subcarriers to individual users. This allows simultaneous low-data-rate transmission from several users.
Extremely high frequency - Wikipedia
https://en.wikipedia.org/wiki/Extremely_high_frequencyWebExtremely high frequency (EHF) is the International Telecommunication Union (ITU) designation for the band of radio frequencies in the electromagnetic spectrum from 30 to 300 gigahertz (GHz). It lies between the super high frequency band and the far infrared band, the lower part of which is the terahertz band. Radio waves in this band have wavelengths …
UMTS frequency bands - Wikipedia
https://en.wikipedia.org/wiki/UMTS_frequency_bandsWebThe UMTS frequency bands are radio frequencies used by third generation (3G) wireless Universal Mobile Telecommunications System networks. They were allocated by delegates to the World Administrative Radio Conference (WARC-92) held in Málaga-Torremolinos, Spain between 3 February 1992 and 3 March 1992. Resolution 212 (Rev.WRC-97), …
Frecvență - Wikipedia
https://ro.wikipedia.org/wiki/FrecvențăWebFrecvența este măsura numărului de repetări ale unui fenomen periodic în unitatea de timp. În Sistemul Internațional unitatea pentru frecvență este numită hertz și este simbolizată prin Hz, în cinstea fizicianului german Heinrich Hertz.O frecvență de 1 Hz corespunde unei perioade de repetare de o secundă.De exemplu, putem spune despre o ciocănitoare care …
Radio-frequency microelectromechanical system - Wikipedia
https://en.wikipedia.org/wiki/Radio-frequency_microelectromechanical_systemWebA radio-frequency microelectromechanical system (RF MEMS) is a microelectromechanical system with electronic components comprising moving sub-millimeter-sized parts that provide radio-frequency (RF) functionality. RF functionality can be implemented using a variety of RF technologies. Besides RF MEMS technology, III-V …
Frequency counter - Wikipedia
https://en.wikipedia.org/wiki/Frequency_counterWebOperating principle. Most frequency counters work by using a counter which accumulates the number of events occurring within a specific period of time. After a preset period known as the gate time (1 second, for example), the value in the counter is transferred to a display and the counter is reset to zero. If the event being measured repeats itself with sufficient …
Radio frequency - Wikipedia
https://en.wikipedia.org/wiki/Radio_frequencyWebRadio frequency (RF) is the oscillation rate of an alternating electric current or voltage or of a magnetic, electric or electromagnetic field or mechanical system in the frequency range from around 20 kHz to around 300 GHz.This is roughly between the upper limit of audio frequencies and the lower limit of infrared frequencies; these are the frequencies at which …

