MAX-M10M - Integration manual
downloads all the almanac data and acquires new signals as they become available during
navigation. The tracking engine consumes less power than the acquisition engine.
The current consumption is lower when a valid position is obtained quickly after the start of the
receiver navigation, the entire almanac has been downloaded, and the ephemeris for each satellite
in view is valid. If these conditions are not met, the search for the available satellites takes more time
and consumes more power.
3.6.2 Power save mode
Power save mode (PSM) allows a reduction in system power consumption by selectively switching
parts of the receiver on and off. It is enabled with CFG-PM-OPERATEMODE and configured with
items in the CFG-PM group.
Power save mode (PSM) has two modes of operation:
•
Power save mode cyclic tracking (PSMCT)
operation is used when position fixes are required in
short periods of 0.5 s to 10 s.
•
Power save mode on/off (PSMOO)
operation is used for periods longer than 10 s, and can be in
the order of minutes, hours, or days.
The mode of operation can be configured, and depending on the setting, the receiver demonstrates
different behavior. In on/off operation the receiver switches between phases of startup/navigation
and phases with low or almost no system activity (backup/sleep). In cyclic tracking the receiver does
not shut down completely between fixes, but uses low-power tracking instead.
In PSMOO mode, the RAM memory is cleared during the off periods. Consequently, store the
configuration in the BBR memory to maintain the settings.
GPS, GLONASS, BeiDou B1I, Galileo and QZSS signals are supported in power save mode. BeiDou
B1C signal is not supported. The receiver is unable to download or process any SBAS data in power
save mode and it is therefore recommended to disable SBAS.
BeiDou B1C is not supported in power save mode.
3.6.2.1 Operation
PSM is based on a state machine with five different states: Inactive for update, Inactive for search,
Acquisition, Tracking and Power optimized tracking (POT) state.
• Inactive states: most parts of the receiver are switched off.
• Acquisition state: the receiver actively searches for and acquires signals. Maximum power
consumption.
• Tracking state: the receiver continuously tracks and downloads data. Less power consumption
than in the acquisition state.
• POT state: the receiver repeatedly loops through a sequence of tracking (Track), calculating
the position fix (Fix), and entering an idle period (Idle). No new signal is acquired and no data is
downloaded. The power consumption is much lower than in the tracking state.
The PSM state machine is described in
.
UBX-22038241 - R02
3 Receiver functionality
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