Bird Technologies AT-800-Manual User Manual

Page 39

Measure Match

Rho

The ratio of reflected wave voltage to forward wave
voltage.

Note:

A perfect antenna would not have any

reflected waves and a 0.00 reflection coefficient.

VSWR

The ratio of maximum and minimum voltages on a
transmission line caused by the combination of a for-
ward and reflected wave.

Note:

For a perfect antenna the VSWR

would be 1:1 and shown as 1.00.

Match Efficiency (%)

Indicates how much of the transmitted power is being
used and how much is wasted.

Note:

A perfect antenna has a Match Effi-

ciency of 100%.

Return Loss (dB)

The ratio of the reflected and forward signal in deci-
bels. If the antenna system is perfectly matched, the
Return Loss would be negative infinity dB.

Note:

Cellular systems and antenna man-

ufacturers often use VSWR in specs.

Note:

Match Efficiency is popular for test-

ing because it is easy to determine a good
match versus a bad match.

Example - A system with a VSWR of 1.50
would show -13.98 dB Return Loss and 96%
Match Efficiency.