I am planning to make a device which operates at 915Mhz frequency and trying to make it compliance to FCC rules. No frequency hopping.
I am not sure whether I should follow 15.245 or 15.247 as it seems there might be some contradictions:
In 15.245, it says the maximum field strength of fundamental is 500mV/M
while in 15.249, it says the maximum field strength of fundamental is just 50mV/M
It's all in the FCC text. In a short, the 500 mV/m (about 19 dBm ERP) applies for wide band and frequency hopping transmitters.
A brief explanation under which prerequisites the higher field strength limits can be utilized is given in TI design note DN036
**broken link removed**
I'm no so familiar with interpretation of FCC regulations, but I read from §15.35, that averaging is only applied above 1000 MHz, while regular quasi peak measurement has to be used below 1000 MHz.