Ublox MAX-7C-0, Руководство пользователя

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MAX-7 / NEO-7 - Hardware Integration Manual
UBX-13003704 - R09 Production Information Product
handling
Page 46 of 52

Layout optimization
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Filtering
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Placement of the GPS antenna
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Adding a CDMA, GSM, WCDMA band pass filter before handset antenna
7.3.7.4 Out-band jamming
Out-band jamming is caused by signal frequencies that are different from the GPS carrier (see Figure 37). The
main sources are wireless communication systems such as GSM, CDMA, WCDMA, Wi-Fi, BT, etc.
Figure 37: Out-band jamming signals
Measures against out-band jamming include maintaining a good grounding concept in the design and adding a
SAW or band pass ceramic filter (as recommend in
Section 5.3.5 ) into the antenna input line to the GNSS
receiver (see Figure 38).
Figure 38: Measures against in-band jamming
For design-in recommendations in combination with cellular operation, see A.2
S ee the GPS Implementation and Aiding Features in u-blox wireless modules [9]