FCC – Wireless Transmitter Frequency Stability Accuracy

Recently, We learned from FCC about the frequency stability requirements for 902 - 928 MHz wireless transmitters. We advised our client that transmitters that operate within the 902 - 928 MHz band are subject to FCC 47CFR15.249. The wireless transmitter carrier’s 20 dB bandwidth must be within the 902 - 928 MHz frequency band where operation is permitted under all conditions including modulation, frequency sweeping, hopping and stability, the frequency tolerance of the carrier, and over variation in temperature.

The frequency accuracy of your wireless transmitter carrier’s signal must be within ±0.001% of the operating frequency over a temperature variation of −20 degrees to +50 degrees C at normal supply voltage, as well as for variation in the primary supply voltage from 85% to 115% of the rated supply voltage at a temperature of 20 degrees C. If your wireless transmitter is battery operated, it must be tested using a new battery.