BandRich BandLuxe M250, User Manual

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y
USIM_CLK and USIM_RST signal, include 33pF filter capacitors is required to be placed near
the SIM connector.
y
Route all USIM signals carefully – isolate them from sensitive analog and RF signals.
y
External ESD diodes are necessary to protect the chip on the module; the ESD diodes should be
placed near the connector.
y
Refer to the reference circuits below:
1.6 Figure 1-6 Antenna Guidelines and RF Connection
This section describes general guidelines for the design of multi-band antenna required for the M250
module series.
1.6.1 Antenna specifications
Frequency range
y
GSM850 (824-894 MHz)
y
EGSM900 (880-960 MHz)
y
DCS1800 (1710-1880 MHz)
y
PCS1900 (1850-1990 MHz)
y
WCDMA 850/1900/2100 (824-894 / 1850-1990 / 1920-2170 MHz)
y
GPS (1575.42MHz±1.023MHz)
Maximum permitted peak gain : -5.8dBi at 850MHz and -0.31dBi at 1850MHz
Maximum VSWR
y
< 2.5:1 with 50 reference impedance
Polarization
y
Linear
1.6.2 Antenna connector
The antenna connector type used is a U.FL microwave coaxial connector. It is also can be used for
testing purpose.
Figure 1-7 Antenna Connector Position and Type
Main Antenna
Connector
GPS RF Connector
Diversity Antenna
Connector