Gnss; Gnss Technical Specification; Gnss Application Guide - SimCom SIM7000 Hardware Design

4.3

GNSS

SIM7000 merges GNSS (GPS/GLONASS/BD) satellite and network information to provide a
high-availability solution that offers industry-leading accuracy and performance. This solution
performs well, even in very challenging environmental conditions where conventional GNSS
receivers fail, and provides a platform to enable wireless operators to address both location-based
services and emergency mandates.
4.3.1

GNSS Technical specification

Tracking sensitivity: -162 dBm（GPS）/-157 dBm（GLONASS）/TBD (BD)

Cold-start sensitivity: -148 dBm

Accuracy (Open Sky): 2.5m (CEP50)

TTFF (Open Sky) : Hot start <1s, Cold start<35s

Receiver Type: 16-channel, C/A Code

GPS L1 Frequency: 1575.42±1.023MHz

GLONASS: 1597.5~1605.8 MHz

BD: 1559.05~1563.14 MHz

Update rate: Default 1 Hz

GNSS data format: NMEA-0183

GNSS Current consumption : 30mA (GSM/LTE Sleep, in total on VBAT pins)

GNSS antenna: Passive/Active antenna

Note: If the antenna is active type, the power should be given by main board because there is no
power supply on the GPS antenna pad. If the antenna is passive, it is suggested that the external
LNA should be used.
4.3.2

GNSS Application Guide

Users can adopt an active antenna or a passive antenna to SIM7000. If using a passive antenna, an
external LNA is a must to get better performance. The following figures are the reference circuits.
GND
GNSS_ANT
GND
MODULE
SIM7000 _Hardware Design _V1.04
Matching circuit
54
C1
L1
Figure 27: Active antenna circuit
Smart Machine Smart Decision
VDD
10 ohm
GNSS Active ANT
47nH
C2
33pF
L2
2018-1-31