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- A transmission medium (plural transmission media) is a material substance which can propagate energy waves. For example, the transmission medium for sound received by the ears is usually air, but solids and liquids may also act as transmission media for sound. The absence of a material medium (the vacuum of empty space) can also be thought of as a transmission medium for electromagnetic waves such as light and radio waves. While material substance is not required for electromagnetic waves to propagate, such waves are usually affected by the transmission media through which they pass, for instance by absorption or by reflection or refraction at the interfaces between media. The term transmission medium can also refer to the technical device which employs the material substance to transmit or guide the waves. Thus an optical fiber or a copper cable can be referred to as a transmission medium. A transmission medium can be classified as a: Linear medium, if different waves at any particular point in the medium can be superposed; Bounded medium, if it is finite in extent, otherwise unbounded medium; Uniform medium or homogeneous medium, if its physical properties are unchanged at different points; Isotropic medium, if its physical properties are the same in different directions. Electromagnetic radiation can be transmitted through an optical media, such as optical fiber, or through twisted pair wires, coaxial cable, or dielectric-slab waveguides. It may also pass through any physical material which is transparent to the specific wavelength, such as water, air, glass, or concrete. Sound is, by definition, the vibration of matter, so it requires a physical medium for transmission, as does other kinds of mechanical waves and heat energy. Historically, various aether theories were used in science and thought to be necessary to explain the transmission medium. However, it is now known that electromagnetic waves do not require a physical transmission medium, and so can travel through the "vacuum" of free space. Regions of the insulative vacuum can become conductive for electrical conduction through the presence of free electrons, holes, or ions.
- Als Übertragungsmedium bezeichnet man eine Technologie zur Übermittlung optischer oder akustischer Signale über Distanzen; ein Material oder einen Stoff, der zur Übertragung von Signalen genutzt werden kann. Bei Schallwellen dient meistens Luft als Übertragungsmedium.
- El medio de transmisión constituye el canal que permite la transmisión de información entre dos terminales en un sistema de transmisión. Las transmisiones se realizan habitualmente empleando ondas electromagnéticas que se propagan a través del canal. A veces el canal es un medio físico y otras veces no, ya que las ondas electromagnéticas son susceptibles de ser transmitidas por el vacio.
- Quindi si può dare la seguente definizione: i canali entro i quali viaggiano i segnali rappresentativi dell'informazione sono detti mezzi trasmissivi; ne consegue anche l'equivalenza tra i termini "mezzo trasmissivo" e "canale trasmissivo". Un canale di trasmissione ideale dovrebbe possedere una banda sufficientemente larga ed uniforme per contenere lo spettro del segnale di informazione senza distorcerlo e dovrebbe poterlo trasferire a qualsivoglia distanza senza introdurre degradamenti nella qualità elettrica di origine; la realtà risulta diversa in quanto sono presenti fattori di degradazione tipici quali: - Attenuazione - Rumore di natura elettrica o segnali spuri - Distorsione
- Medium transmisyjne jest nośnikiem używanym do transmisji sygnałów w telekomunikacji i jest podstawowym elementem systemów telekomunikacyjnych. Możliwości transmisji zależą od parametrów użytego medium. Wyróżnia się media przewodowe i bezprzewodowe.
- Transmissionsmedium är ett materia genom vilken energi kan fortplanta sig i någon form. Mekaniska vågor, till exempel ljud, sprids genom alla typer av materia i någon mån. Elektrisk ström sprids genom elektriska ledare. Elektromagnetisk strålning sprids genom vissa typer av materia, men kan även spridas genom vakuum. Förr trodde man att eter var den elektromagnetiska strålningens transmissionsmedium. Värme sprids genom elektromagnetisk strålning, genom konvektion eller värmeledning.
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- A transmission medium (plural transmission media) is a material substance which can propagate energy waves. For example, the transmission medium for sound received by the ears is usually air, but solids and liquids may also act as transmission media for sound. The absence of a material medium (the vacuum of empty space) can also be thought of as a transmission medium for electromagnetic waves such as light and radio waves.
- Als Übertragungsmedium bezeichnet man eine Technologie zur Übermittlung optischer oder akustischer Signale über Distanzen; ein Material oder einen Stoff, der zur Übertragung von Signalen genutzt werden kann. Bei Schallwellen dient meistens Luft als Übertragungsmedium.
- El medio de transmisión constituye el canal que permite la transmisión de información entre dos terminales en un sistema de transmisión. Las transmisiones se realizan habitualmente empleando ondas electromagnéticas que se propagan a través del canal. A veces el canal es un medio físico y otras veces no, ya que las ondas electromagnéticas son susceptibles de ser transmitidas por el vacio.
- Quindi si può dare la seguente definizione: i canali entro i quali viaggiano i segnali rappresentativi dell'informazione sono detti mezzi trasmissivi; ne consegue anche l'equivalenza tra i termini "mezzo trasmissivo" e "canale trasmissivo".
- Medium transmisyjne jest nośnikiem używanym do transmisji sygnałów w telekomunikacji i jest podstawowym elementem systemów telekomunikacyjnych. Możliwości transmisji zależą od parametrów użytego medium. Wyróżnia się media przewodowe i bezprzewodowe.
- Transmissionsmedium är ett materia genom vilken energi kan fortplanta sig i någon form. Mekaniska vågor, till exempel ljud, sprids genom alla typer av materia i någon mån. Elektrisk ström sprids genom elektriska ledare. Elektromagnetisk strålning sprids genom vissa typer av materia, men kan även spridas genom vakuum. Förr trodde man att eter var den elektromagnetiska strålningens transmissionsmedium. Värme sprids genom elektromagnetisk strålning, genom konvektion eller värmeledning.
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