What is VSWR dB? - RF Cafe Forums

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celltron

Post subject: What is VSWR dB?

Posted: Wed Aug 13, 2008 7:46 am

Lieutenant

Joined: Sat Jun 28, 2008 10:17 am
Posts: 1

In the course of reviewing basic coax cable testing it was decided to develop a spreadsheet calculator. A recent find was a table that had the following columns

|VSWR|VSWR(dB)|RETURN LOSS|TRANS LOSS|REFL COEF|POWER TRANS%|POWER REFL.%|

I've found equations to relate each column to the other columns except for column VSWR (dB). It seems like return loss and transmission (mismatch) loss account for power loss due to VSWR so I don't know what this column references. Can anyone provide an equation and explanation for this column?

Any help is appreciated.

Kirt Blattenberger

Post subject:

Posted: Wed Aug 13, 2008 4:46 pm

Site Admin

Joined: Sun Aug 03, 2003 2:02 pm
Posts: 476
Location: Erie, PA

Gings celltron:

All of the formulas for converting between the forms of reporting VSWR can be found on the following page (there's a calculator there for you, too).

VSWR - Return Loss - Gamma Conversions

Thanks for posting.

_________________
- Kirt Blattenberger :smt024

RF Cafe Progenitor & Webmaster

Posted 11/12/2012