antenna coupling的意思|示意

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Antenna coupling, in the context of antenna engineering, is a measure of how well two antennas transfer energy to each other when they are placed close together. It is used to measure the energy efficiency of an antenna system, and also helps in the design and characterization of antenna elements.

The coupling between two antennas is typically expressed in a measure known as the antenna coupling factor (ACF). The ACF is a measure of the energy lost between two antennas due to their near proximity, and can be expressed as a percentage. A higher ACF indicates a higher level of energy efficiency.

One way to measure the ACF is with a Smith chart, which is a graphical tool used by antenna engineers to measure the parameters of an antenna system. The Smith chart shows the antenna coupling factor as well as other parameters such as antenna efficiency and antenna radiation patterns.

The ACF can also be determined experimentally, by measuring the transmitted power at a given frequency between two antennas that are positioned close together. This is done by measuring the power spectral density (PSD) of the system, which is the total power (in watts) divided by the bandwidth (in Hz) of the signal. The PSD is then compared to the noise floor of the system, which is the minimum power (in dBm) required for the signal to be detectable.

The ACF can also be used to determine the strength of the electromagnetic field from an antenna, which is a measure of the distance between two antennas. An antenna with a higher ACF will produce a stronger electromagnetic field, allowing it to transmit its signal further than an antenna with a lower ACF.

In summary, antenna coupling is a measure of how well two antennas transfer energy to each other when they are placed close together. It is expressed as a percentage and is used to measure the energy efficiency of an antenna system. It can be calculated with a Smith chart or experimentally by measuring the transmitted power between two antennas that are placed close together.