Free-space path loss

（重定向自Free space loss）

A 2D Cartesian plot showing the FSPL against distance for fixed frequencies of 2.4 GHz, 5.1 GHz and 5.7 GHz

A plot of the FSPL for a range of fixed frequencies. FSPL increases with increasing frequency.

In telecommunication, free-space path loss (FSPL) is the loss in signal strength of an electromagnetic wave that would result from a line-of-sight path through free space (usually air), with no obstacles nearby to cause reflection or diffraction. It is defined in "Standard Definitions of Terms for Antennas", IEEE Std 145-1983, as "The loss between two isotropic radiators in free space, expressed as a power ratio." Usually it is expressed in dB, although the IEEE standard does not say that. So it assumes that the antenna gain is a power ratio of 1.0, or 0 dB. It does not include any loss associated with hardware imperfections, or the effects of any antennas gain. A discussion of these losses may be found in the article on link budget. The FSPL is rarely used standalone, but rather as a part of the Friis transmission equation, which includes the gain of antennas.

单词	Free space loss
释义	Free space loss 英语百科 Free-space path loss （重定向自Free space loss） In telecommunication, free-space path loss (FSPL) is the loss in signal strength of an electromagnetic wave that would result from a line-of-sight path through free space (usually air), with no obstacles nearby to cause reflection or diffraction. It is defined in "Standard Definitions of Terms for Antennas", IEEE Std 145-1983, as "The loss between two isotropic radiators in free space, expressed as a power ratio." Usually it is expressed in dB, although the IEEE standard does not say that. So it assumes that the antenna gain is a power ratio of 1.0, or 0 dB. It does not include any loss associated with hardware imperfections, or the effects of any antennas gain. A discussion of these losses may be found in the article on link budget. The FSPL is rarely used standalone, but rather as a part of the Friis transmission equation, which includes the gain of antennas.
随便看	verminous crasis verminous dermatitis verminous pneumonia vermin proof verminproof verminulous verminum verminy Vermion vermiontic Vermio Oros Vermiosa vermiparous vermiphobia Vermipodium Vermirax vermis vermis cerebelli vermis cerebellis vermis cerebellum vermis inferior vermis of anterior lobe Vermis of cerebellum vermisol vermisols