Quality

The Quality tab is used to specify quality thresholds for your GPS receiver. The thresholds affect GPS data capture and alerts but do not affect the GPS cursor, GPS Position Window, or GPS navigation.

No Warnings/Non-Compulsory Warnings/Compulsory Warnings

When No Warnings is selected, none of the GPS quality thresholds are applied when you capture GPS positions.

When Non-Compulsory Warnings is selected, the specified GPS quality thresholds are applied when you capture GPS positions; however, you will have the option to capture the GPS positions when the quality thresholds are exceeded.

When Compulsory Warnings is selected, the specified GPS quality thresholds are applied when you capture GPS positions. You cannot capture GPS positions if the quality thresholds are exceeded.

The default is No Warnings selected.

Maximum [PDOP]

You can chose up to two quality parameters to define maximum values for.

When one of the maximum check boxes are checked, a quality control is placed on the quality parameter selected. By default Positional Dilution of Precision (PDOP) of incoming GPS positions is chosen for the first maximum value. The value in the box to the right specifies the maximum allowable PDOP. A maximum PDOP of 6 is generally considered acceptable.

This affects you in the following ways:

1. If the PDOP of the current GPS position exceeds the maximum value while you are capturing a feature using the GPS, you will either get a warning message or not be allowed to capture data until the PDOP is less than or equal to the specified value, depending on whether Non-Compulsory Warnings or Compulsory Warnings is selected.
2. If the Maximum PDOP exceeded check box on the Alerts tab is checked, an alert message and/or sound occurs whenever the PDOP of the current GPS position exceeds the maximum value.

Other values that can chosen in place of PDOP are: HDOP, VDOP, TDOP, EPE, VPE, DAGE.

The default is unchecked and no value is specified.

Maximum [EPE]

This field is used in the same way as the one described above.

When the second maximum check box is checked, a quality control is placed on the quality parameter selected. By default the Estimated Position Error (EPE) of incoming GPS positions is chosen for the second maximum value. The value in the box to the right specifies the maximum allowable EPE. The maximum allowable EPE you use should correspond directly to the maximum distance error you can accept. For example, if you can accept a maximum distance error of 15 meters, you should set the maximum allowable EPE to 15—assuming your display units are set to metric on the Display tab of the ArcPad Options dialog box. EPE is only output by Garmin GPS receivers as part of a proprietary Garmin message, so this setting is only valid when using a Garmin GPS receiver.

This affects you in the following ways:

1. If the EPE of the current GPS position exceeds the maximum value while you are capturing a feature using the GPS, you will either get a warning message or not be allowed to capture data until the EPE is less than or equal to the maximum value, depending on whether Non-Compulsory Warnings or Compulsory Warnings is selected.
2. If the Maximum EPE Exceeded check box on the Alerts tab is checked, an alert message and/or sound occurs whenever the EPE of the current GPS position exceeds the specified value.

Other values that can chosen in place of PDOP are: HDOP, VDOP, TDOP, EPE, VPE, DAGE.

The default is unchecked and no value is specified.

[DGPS Only]

When checked, a quality control is placed on the differential status of incoming GPS positions.

This affects you in the following ways:

1. If the current GPS position is not a DGPS position while you are capturing a feature using the GPS, you will either get a warning message or not be allowed to capture data until a DGPS position is received, depending on whether Non- Compulsory Warnings or Compulsory Warnings is selected.
2. If the Not a DGPS Fix check box on the Alerts tab is checked, an alert message and/or sound occurs whenever the current GPS position is not a DGPS position.

Other values that can chosen in place of DPS Only are: RTK Float or Fixed, RTK Fixed PPS Only.

The default is unchecked.

When checked, a quality control is placed on the altitude status of incoming GPS positions.

This affects you in the following ways:

1. If the current GPS position is not a three-dimensional position while you are capturing a feature using the GPS, you will either get a warning message or not be allowed to capture data until a three-dimensional position is received, depending on whether Non-Compulsory Warnings or Compulsory Warnings is selected.
2. If the Not a 3D Fix check box on the Alerts tab is checked, an alert message and/or sound occurs whenever the current GPS position is not a three-dimensional position.

The default is unchecked.