User's Manual

DE910 Series Hardware User Guide
1vv0300951 Rev.9 2015-05-11
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Reserved. Page 42 of 77
NOTE:
The external GNSS LNA and GNSS pre-Filter shall be required for GLONASS application.
GNSS LNA requirement shall fulfill the following specifications.
Frequency = 1565 ~ 1606MHz
Power Gain|S21|
2
= 14 ~ 17dB
NF < 1dB
GNSS pre-Filter requirement shall fulfill the following requirements.
Source and Load Impedance = 50Ohm
Insertion Loss (1575.42 ~ 1576.42MHz) = 1.4dB (Max)
Insertion Loss (1565.42 ~ 1585.42MHz) = 2.0dB (Max)
Insertion Loss (1597.5515 ~ 1605.886MHZ) = 2.0dB (Max)
The external active antenna for the Telit DE910 device must fulfill the following
requirements:
GNSS Antenna Requirements
Frequency range
1575.42MHz (GPS L1)
1597.55 ~ 1605.89MHz (GLONASS)
Bandwidth
±
1.023MHz
(GPS L1)
8.34MHz (GLONASS)
Impedance
50 Ohm
LNA NF
< 1dB
LNA Gain
14 ~ 17dB
LNA Input Voltage
3.0V or 5.0V
NOTE:
The maximum DC voltage applicable to ANT_GPS pin is 5V. In case this is exceeded, a
series capacitor has to be included in the design to avoid exceeding the maximum input DC
level.