Aviation dictionary. 2014.
Guard band — has several meanings. NOTOC Radio and electronic signallingIn radio, a guard band is an unused part of the radio spectrum between radio bands, for the purpose of preventing interference.It is a narrow frequency range used to separate two wider… … Wikipedia
Guard — may refer to:Professional occupations* Bodyguard, who protects an individual from personal assault * Crossing guard, who stops traffic so pedestrians can cross the street * Prison guard, who supervises prisoners in a prison or jail * Security… … Wikipedia
Guard tone — is a feature of wireline modems.The guard tone is sent by the answering modem after it has sent the answer tone. It is a single continuous tone with a frequency of either 1800 Hz or 550 Hz, sent at a level of 6dB or 3dB, respectively, below the… … Wikipedia
Frequency Division Multiple Access — Multiplexverfahren (lat. multiplex „vielfach, vielfältig“) sind Methoden zur Signal und Nachrichtenübertragung, bei denen mehrere Signale zusammengefasst (gebündelt) und simultan über ein Medium (Leitung, Kabel oder Funkstrecke) übertragen werden … Deutsch Wikipedia
frequency-division multiplexing — Abbreviated FDM. A method of sharing a transmission channel by dividing the bandwidth into several parallel paths, defined and separated by guard bands of different frequencies designed to minimize interference. All signals are carried… … Dictionary of networking
guard band — A small frequency band used to separate multiple bands in a broadband transmission and prevent interference between the communications channels … Dictionary of networking
guard band — The portions of two adjacent frequency bands that remain unused and provide a mutual interference safety margin … IT glossary of terms, acronyms and abbreviations
Aircraft emergency frequency — The aircraft emergency frequency (also known as guard) is a frequency used on the aircraft radio band reserved for emergency communications for aircraft in distress. The frequencies are 121.5 MHz for civilian, also known as International Air… … Wikipedia
Orthogonal frequency-division multiplexing — Passband modulation v · d · e Analog modulation AM · … Wikipedia
Single-frequency network — For other uses, see SFN (disambiguation). A single frequency network or SFN is a broadcast network where several transmitters simultaneously send the same signal over the same frequency channel. Contents 1 Overview 2 OFDM and COFDM 3 DVB T SFN … Wikipedia
