Chapter 3 OEM7 Receiver Operation
CPT7 and CPT7700 Installation and Operation User Manual v12
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Figure 14: Positioning Change Without STEADYLINE
The STEADYLINE feature internally monitors the position offsets between all the GNSS positioning modes
present in the receiver. When the current positioning mode becomes unavailable, the receiver transitions to
the next most accurate positioning mode.
Refer to the
OEM7 Commands and Logs Reference Manual
for log and command details.
3.5.1 Prefer Accuracy
The positioning mode change depends on the accuracy level of the positioning modes.
When the position mode is changing from a more accurate mode to a less accurate mode (e.g., changing from
RTK to GLIDE), the receiver uses the position offset calculated to limit a potential real position jump.
When the position mode is changing from a less accurate mode to a more accurate mode (e.g., GLIDE to
RTK), the receiver slowly transitions to the new reference position type over the time period specified by the
Transition time parameter.
For example, a receiver is configured to do both RTK and GLIDE. If this receiver has a fixed RTK position and
experiences a loss of correction data causing the loss of the RTK solution it will immediately apply the offset
between the two position modes and uses the GLIDE position stability to maintain the previous trajectory.
Over time the GLIDE (or non-RTK) position will experience some drift. Once the RTK position is achieved
again the receiver will start using the RTK positions for position stability and will slowly transition back to the
RTK positions at a default rate of 0.005 m/s or the time specified in the
STEADYLINE
command.
Figure 15: STEADYLINE Prefer Accuracy
3.6 Enabling SBAS Positioning
OEM7 receivers are capable of SBAS positioning. This positioning mode is enabled using the
SBASCONTROL
command:
sbascontrol enable auto
When the command is entered, the OEM7 receiver automatically tracks the SBAS that is operating in the
region (e.g., WAAS or EGNOS) and applies the corrections from the service. On a simulator, leave the test
mode parameter off or specify NONE explicitly. For more on SBAS, refer to application note
Positioning Modes of Operation
(additional Application Notes available at
) and the known solution
