User's Manual

LE920 Hardware User Guide
1vv0301026 Rev.8 2015-01-03
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In the case that the antenna is not directly connected at the antenna pad of the LE920, then a
PCB line is required in order to connect with it or with its connector.
The second Rx antenna should not be located in the close vicinity of the main antenna. In order
to improve Diversity Gain, Isolation and reduce mutual interaction, the two antennas should be
located at the maximum reciprocal distance possible, taking into consideration the available
space within the application.
NOTE:
If the RX Diversity is not used/connected, disable the Diversity functionality using the
AT#RXDIV command (refer to the AT User guide) and leave the Diversity pad AU9
unconnected.
6.5. GPS/GNSS Antenna Requirements
LE920 supports an active antenna.
It is recommended to use antennas as follow:
An external active antenna (GPS only).
An external active antenna, GNSS pre-filter.
NOTE:
Released models LE920-NA cs1550f-A & LE920-EU cs1550f-B include internal LNA
(13.5dB gain typ.).
For LE920-NA cs1550f-A & LE920-EU cs1550f-B models it is recommended to use:
• An external passive antenna (GPS only).
• An external passive antenna, GNSS pre-filter.
NOTE:
The external GNSS pre-Filter shall be required for GLONASS application.
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)