Post by HighMountainRadio on Mar 17, 2018 4:17:50 GMT -6
Greeting From High Mountain Radio !
While doing research for an antenna project I have discovered an excellent online VSWR (SWR) calculator ! This website contains an outstanding explanation of the criteria that must be met in order to ensure proper antenna installation and impedance matching ! The information presented is written in a clear and concise manner at a technical level that is easy to comprehend, thus, the opportunity for even those individuals who may be a novice to gain a clear understanding of what is required to achieve the maximum potential of the antenna system. You may find it here: rf-tools.com/vswr/
For any antenna installation, regardless of the frequency spectrum, it is imperative to correctly match the impedance of the transmitter to that of the antenna being utilized in order to achieve maximum performance results ! Using this terrific online calculator will enable you to quickly and easily determine the following criteria with regard to the measured VSWR - Voltage Standing Wave Ratio (Often simply referred to as 'SWR') on any RF transmission path: Return Loss (db), Mismatch Loss (db), Reflected Power (%) and Voltage Reflection Coefficient.
VSWR (Voltage Standing Wave Ratio) – Defined as the ratio between the partial standing wave maximum and minimum amplitude along the transmission line. VSWR values range from 1 for a perfect impedance match to infinity for a total reflection.
Return Loss – The power of the reflected signal expressed in dB relative to the incident power. Return Loss values range from infinity for a perfect impedance match to 0 dB for a total reflection.
Mismatch Loss – The transmitted signal power loss expressed in dB relative to the incident power. Mismatch Loss values range from 0dB for a perfect impedance match to infinity for a total reflection.
Reflected Power - The power of the reflected signal expressed as a percentage relative to the incident power. Reflected Power values range from 0% for a perfect impedance match to 100% for a total reflection.
Voltage Reflection Coefficient – the amplitude ratio of the reflected signal to the incident signal. Voltage Reflection Coefficient values range from 0 for a perfect impedance match to 1 for a total reflection.
When an incident signal propagates along a transmission line into a load (antenna), some part of the its power will be reflected back down the line. The power transfer efficiency depends on the impedance match between the load (antenna) and the transmission line. When the impedances are equal, the whole signal power is delivered to the load (antenna). In real life there is always some degree of impedance mismatch and as a result, back reflections.
In high power applications like transmitter to antenna interface, reflections have significant power that may damage the previous source stage (transmitter output stage).
I trust that you will find this online calculator as useful as I have ! I highly encourage anyone that plans to install a new antenna or work with an antenna system to study this information as it will prove to be invaluable to ensure that your transmitter, transmission line and antenna are operating at peak efficiency ! When broadcasting at relatively low RF power levels, it is imperative to ensure that every available milliwatt is transferred efficiently to the antenna to ensure maximum broadcast potential !
Keep On Rockin' In The Free World !
73... Spooky...
"Knowledge Is Always Made More Valuable By Sharing It With Others !" Always Remember To Be Kind ! True Greatness Often Has Very Humble Beginnings ! Help A Kid Out Today ! *** High Mountain Radio *** "Broadcasting From Somewhere High In The Remote Appalachian Mountains"
Post by HighMountainRadio on Mar 21, 2018 17:35:57 GMT -6
Hey Tester !
Glad you found it to be useful ! Thanks for your comment !
73... Spooky...
"Knowledge Is Always Made More Valuable By Sharing It With Others !" Always Remember To Be Kind ! True Greatness Often Has Very Humble Beginnings ! Help A Kid Out Today ! *** High Mountain Radio *** "Broadcasting From Somewhere High In The Remote Appalachian Mountains"
