Layout Guidelines - Quectel EG91 Series Hardware Design

Hot start
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Accuracy
CEP-50
(GNSS)
NOTES
1. Tracking sensitivity: the lowest GNSS signal value at the antenna port on which the module can keep
on positioning for 3 minutes.
2. Reacquisition sensitivity: the lowest GNSS signal value at the antenna port on which the module can
fix position again within 3 minutes after loss of lock.
3. Cold start sensitivity: the lowest GNSS signal value at the antenna port on which the module fixes
position within 3 minutes after executing cold start command.
The following layout guidelines should be taken into account in customers' design.
Maximize the distance among GNSS antenna, main antenna and Rx-diversity antenna.

 Digital circuits such as (U)SIM card, USB interface, camera module and display connector should be
kept away from the antennas.
 Use ground vias around the GNSS trace and sensitive analog signal traces to provide coplanar
isolation and protection.
 Keep the characteristic impedance for ANT_GNSS trace as 50Ω.
Please refer to Chapter 5 for GNSS antenna reference design and antenna installation information.
EG91_Hardware_Design
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4.3. Layout Guidelines

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LTE Module Series
EG91 Hardware Design
1.8 s
3.4 s
<2.5 m