frequency telegraphy

См. также в других словарях:

• voice-frequency telegraphy — toninė telegrafija statusas T sritis radioelektronika atitikmenys: angl. voice frequency telegraphy vok. Wechselstromtelegraphie, f rus. тональная телеграфия, f pranc. télégraphie par fréquences vocales, f …   Radioelektronikos terminų žodynas

• Telegraphy — (from the Greek words (τηλε) = far and (γραφειν) = write) is the long distance transmission of written messages without physical transport of letters. Radiotelegraphy or wireless telegraphy transmits messages using radio. Telegraphy includes… …   Wikipedia

• Frequency-division multiplexing — (FDM) is a form of signal multiplexing where multiple baseband signals are modulated on different frequency carrier waves and added together to create a composite signal. Non telephoneFDM can also be used to combine multiple signals before final… …   Wikipedia

• Frequency-hopping spread spectrum — (FHSS) is a method of transmitting radio signals by rapidly switching a carrier among many frequency channels, using a pseudorandom sequence known to both transmitter and receiver. A spread spectrum transmission offers three main advantages over… …   Wikipedia

• Frequency shift — In the physical sciences and in telecommunication, the term frequency shift has the following meanings: * Any change in frequency * A Doppler shift * Any change in the frequency of a radio transmitter or oscillator. (Note: In the radio regime,… …   Wikipedia

• frequency-shift telegraphy — dažnio manipuliacijos telegrafija statusas T sritis radioelektronika atitikmenys: angl. frequency shift telegraphy vok. Frequenzumtasttelegrapfie, f rus. телеграфия с частотной манипуляцией, f pranc. télégraphie à déplacement de fréquence, f …   Radioelektronikos terminų žodynas

• Multiple frequency-shift keying — Passband modulation v · d · e Analog modulation AM · …   Wikipedia

• Dual-tone multi-frequency signaling — One of the few production telephone DTMF keypads with all 16 keys, from an Autovon Telephone. The column of red keys produces the A, B, C, and D DTMF events. Dual tone multi frequency signaling (DTMF) is used for telecommunication signaling over… …   Wikipedia

• GSM frequency bands — or frequency ranges are the cellular frequencies designated by the ITU for the operation of GSM mobile phones. Contents 1 GSM frequency bands 1.1 GSM 900, GSM 1800 and EGSM/EGSM 900 1.1.1 GSM 1800 …   Wikipedia

• Wireless telegraphy — Wireless Wire less, a. Having no wire; specif. (Elec.), designating, or pertaining to, a method of telegraphy, telephony, or other information transmisssion, in which the messages, data, etc., are transmitted through space by electric waves; as,… …   The Collaborative International Dictionary of English

• Acoustic telegraphy — was also known as harmonic telegraphy. During the 1800s inventors tried to find ways of sending multiple telegraph messages simultaneously over a single telegraph wire by using different audio frequencies for each message. These inventors… …   Wikipedia