MOVINGBASESTATION

Enables the use of a moving base station

Platform:

OEM719, OEM729, OEM7500, OEM7600, OEM7700, OEM7720, PwrPak7, CPT7, CPT7700, SMART7, SMART2

This command is used to enable or disable a receiver from transmitting corrections without a fixed position.

The moving base function allows you to obtain a centimetre level xyz baseline estimate when the base station and possibly the rover are moving. It is very similar to normal RTK, with one stationary base station and a moving rover (refer to Transmitting and Receiving Corrections). The BSLNXYZ log is an asynchronous ‘matched’ log that can be logged with the onchanged trigger to provide an accurate baseline between the base and rover.

Due to the latency of the reference station position messages, the following logs are not recommended to be used when in moving baseline mode: BESTXYZ, GPGST, MARKPOS, MARK2POS, MATCHEDPOS, MATCHEDXYZ, RTKPOS and RTKXYZ. The position error of these logs could exceed 100 m, depending on the latency of the reference station position message. If a rover position is required during moving basestation mode, then PSRPOS is recommended.

The MOVINGBASESTATION command must be used to allow the base to transmit messages without a fixed position.

 

  1. Use the PSRPOS position log at the rover. It provides the best accuracy and standard deviations when the MOVINGBASESTATION mode is enabled.

  2. This command supports RTCM V3 operation.

  3. RTCM V3 support includes GPS + GLONASS operation.

Message ID: 763

Abbreviated ASCII Syntax:

MOVINGBASESTATION switch

Factory Default:

MOVINGBASESTATION disable

ASCII Example:

MOVINGBASESTATION ENABLE

 

Consider the case where there is a fixed base, an airplane flying with a moving base station near its front and a rover station at its tail end.
Corrections can be sent between the receivers in a ‘daisy chain’ effect, where the fixed base station sends corrections to the moving base station, which in turn can send corrections to the rover.

Moving Base Station ‘Daisy Chain’ Effect

When using this method, the position type is only checked at the fixed base station. Moving base stations will continue to operate under any conditions.

This command is useful for moving base stations doing RTK positioning at sea. A rover station is used to map out local areas (for marking shipping lanes, hydrographic surveying and so on), while the base station resides on the control ship. The control ship may not move much (parked at sea), but there is a certain amount of movement due to the fact that it is floating in the ocean. By using the MOVINGBASESTATION command, the control ship is able to use RTK positioning and move to new survey sites.

 

Field

Field Type

ASCII Value

Binary Value

Description

Format

Binary Bytes

Binary Offset

1

Command header

-

-

MOVINGBASESTATION header

This field contains the command name for abbreviated ASCII or the message header for ASCII (see page 1) or Binary (see page 1).

-

H

0

2

switch

DISABLE

0

Do not transmit corrections without a fixed position.

Enum

4

H

ENABLE

1

Transmit corrections without a fixed position.