For a portal antenna, with 30 feet of cable between a reader and a far tower, how much dB loss should we offset for? I have heard it's 2 dB for 30 to 45 feet.
The answer would depend on the type of cable you are using. For passive UHF RFID readers, it's best to utilize LMR cables, which are high-performance coaxial communications cables that have different amounts of insulation to limit signal loss. For more than 30 feet, an LMR-195 cable would lose 3.3 dB, but an LMR-600, which has more insulation, would lose just 0.8 dB.
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