HUAWEI ME909u-523 LTE LGA Module
Application Guide
GPS Application Scenarios
Issue 04 (2014-12-08)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
73
NOTE
The MSA method requires the module to register with a network, and incurs data traffic
during positioning. If GPS response time in the positioning QoS is set to a too small value,
the MSA positioning may fail.
During the AGPS positioning process, please do not search the network, because this
operation will influence the positioning time.
11.5 XTRA Positioning
Command
Description
AT^WPDOM=6
Set the positioning method to gpsOneXTRA.
OK
AT^XTRASTA
Query the status of XTRA data. If the date of the
obtained XTRA data is more than seven days
earlier than the current date, the XTRA data is
invalid, and the module needs to download new
XTRA data. (The XTRA data's ability to assist
positioning declines as time goes by. Therefore, it
would be appropriate to set the XTRA data's valid
period to three days. You can also download the
latest XTRA data without querying the existing
XTRA data information.)
OK
^XDSTATUS: 0,0,0,0
Notify XTRA data query result.
AT^XTRATIME
……
Upper layer applications use this command to
access the SNTP server to obtain the current time
information, and inject the information into the
module.
OK
^TIMESETRULT: 0
Notify XTRA time injected result.
AT^XTRADATA
……
Upper layer applications use this command to
access the XTRA server to download XTRA data,
packetize the data, and inject the data into the
module. (You can also inject the XTRA data from
the host into the module.)
There are two types of XTRA files stored on the
XTRA server:
Xtra.bin file: contains predicted two-line orbital
elements for GPS satellites, about 45 KB.
Xtra2.bin file: contains predicted two-line orbital
elements for GPS and GLONASS satellites,
about 80 KB.