Siemens SIMATIC RF600 System Manual page 155

Approximate calculations are easier to carry out as additions than as products, therefore the
logarithms are taken for the above equations and the power data standardized to 1 mW and
specified in decibels (dBm or dBi).
Calculation of the radiated power with consideration of the cable loss a
If the transmitted power is not applied directly but via a cable with loss a
compensated such that the same radiated power is obtained.
If the loss is not appropriately compensated, the radiated power is too small.
SIMATIC RF600
System Manual, 10/2009, J31069-D0171-U001-A8-7618
6.2 Guidelines for selecting RFID UHF antennas
k
Antennas
, this loss should be
K
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