User's Manual

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Note d’étude / Technical document : URD1– OTL 5665.1– 002 / 70 884 Edition 03
Document Sagem Communications Reproduction et divulgation interdites
Sagem Communications document. Reproduction and disclosure prohibited
6. RADIO INTEGRATION
6.1 ANTENNA
- Antenna contact
• 50Ω line matching (between module and customer’s board, and with RF test point)
Figure 20: Antenna connection
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Keep matching circuit on customer’s board but with direct connection in the first step – it could be
necessary to make some adjustment later, during RF qualification stage.
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The selected antenna must comply with FCC RF exposure limits in GSM850 and PCS1900 band :
- GSM850 : MPE < 0.55mW/cm
2
(Distance is 20 cm)
- PCS1900 : ERP < 3W
6.2 GROUND LINK AREA
Sagem Communications emphasizes the fact that a good ground contact is needed between the module and the
customer’s board to have the best radio performances (spurious, sensitivity…).
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All HiloNC GND pads must be connected to the GND of the customer’s board.
6.3 LAYOUT
Warning : Isolate RF line and antenna from others bus or signals
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No signals on 50 ohms area and if that is not possible, add ground shielding using different layers.
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Do not add any ground layer under the antenna contact area.
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Be careful on the position of the network LED (sometimes situated in front of the antenna pad ...)
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Do not put any via and lines on all the forbidden area under the module, shown as the grey area on the
figure below.
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Varnish must be present on all the grey area (expect solder pads) to isolate HiloNC module from the
customer’s board.