RCB-F9T - Integration manual
• Maintaining a good grounding concept in the design
• Shielding
• Layout optimization
• Low-pass filtering of noise sources, e.g. digital signal lines
• Remote placement of the GNSS antenna, far away from noise sources
• Adding an LTE, CDMA, GSM, WCDMA, BT band-pass filter before antenna
4.5.3 Out-of-band interference
Out-of-band interference is caused by signal frequencies that are different from the GNSS carrier
frequency. The main sources are wireless communication systems such as LTE, GSM, CDMA,
WCDMA, Wi-Fi, BT, etc.
Measures against out-of-band interference include maintaining a good grounding concept in the
design and adding a GNSS band-pass filter into the antenna input line to the receiver.
For GSM applications, such as typical handset design, an isolation of approximately 20 dB can be
reached with careful placement of the antennas. If this is insufficient, an additional SAW filter is
required on the GNSS receiver input to block the remaining GSM transmitter energy.
UBX-19003747 - R04
4 Design
Page 48 of 54
Early production information