General Layout Guidelines For Enfora Gsm Modules - Enfora Enabler III-G Integration Manual

Enfora Enabler III-G
Modem Integration Guide
GSM Transmit Power
1800/1900 MHz............................ GSM Power Class 1 (30 dBm ± 2 dB @ antenna connection)
850/900 MHz ................................ GSM Power Class 4 (33 dBm ± 2 dB @ antenna connection)
GSM/GPRS Receiver Sensitivity (Typical)
1800/1900 MHz............................ <-106 dBm, GPRS Coding Scheme 1 (CS1)
850/900 MHz ................................ <-106 dBm, GPRS Coding Scheme 1 (CS1)

4.7. General layout guidelines for Enfora GSM modules

To ensure lowest possible EMI emission, maximum thermal conduction and mechanical integrity, all
metal tabs on the GSM module shield must be soldered down on to a continuous ground plane. The
PCB trace that feeds the RF output port must be 50ohm characteristic impedance, coplanar, or
routed into internal layers to keep the top layer continuous around and underneath the device.
Provide ample ground vias around metal tabs, the RF trace and launch pad. If possible, keep I/O and
power traces away from the RF port.
GSM0308PB001 Version DRAFT – 2/9/2007
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