Following is your data sheet blocker rejection plot. Is this all based on CW tone interferer? Is the rejection better with wideband signals? For curiosity, where does the distortion happen? Is it due to ADC clipping after baseband RC filter?
I have concerns about interferences from Cell phone, Family radio walkie talkie and other higher power radio devices.
Cell phone output power level can be as high as +24dBm per 5MHz bandwidth. LTE signal peak to average is about 12dB. Cell phone frequency is about 2GHz, your rejection is 50dBc. Being conservative, cell phone need to be at least 15 meters away. This might not be acceptable to our application.
FRS walkie talkie output power is up to 3W or 36dBm and very narrowband. Due to AC coupling and balun design, your front end might have significant rejection on low frequency interferers. Is it sufficient to reject such interference.
The bottom line question is that “Do we need front end Band Pass Filter”? If so, what do you recommend?
Thank you for help.
- Sai
