Telit Wireless Solutions HE910-EU V2, Hardware User'S Manual

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Depending on the characteristics and requirements unique to the customer’s designs, the use
of an external LNA or an external active antenna may be required to achieve best
performance.
The optional external LNA should be dimensioned to avoid an excessive LNA gain that can
introduce jamming, spurious, degrade IIP3, and saturate the receiver.
The configurations of an external device must fulfill the following requirements:

An external passive antenna (GPS only)

An external active antenna (GPS or GNSS)

An external passive antenna, GNSS pre-Filter and GNSS LNA (GPS or GNSS)
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)
WARNING:
The HE910 V2 software is implemented differently depending on the configurations of an
external device. Please refer to the AT command User Guide in detail.