Measuring Antenna Height at ARP

Antenna Model

Proper antenna models are required when processing observations collected with survey grade receivers. When selecting the appropriate antenna model, it is possible to reduce slant antenna heights (measured on the field) to vertical heights and to account correctly for antenna phase center vertical offset. This latter issue is particularly important when the user is seeking for centimeter level accuracy and is using antennas of different models at the base and at the remote receiver.

 

For GIS users interested in horizontal components, all settings described in this articles are not important since they are used to get sub-centimeter accuracy in the height component. Moreover, if you are working at sub-meter level accuracy, this information isnít relevant.

 

In EZSurv, an antenna model is defined by a model name, a radius, a measurement mark offset and a vertical offset for L1 and L2 frequencies. The vertical offset for L2 will be zero if the antenna is single frequency. The radius is measured from the center to the edge of the antenna at the measurement mark (when measuring antenna height). The vertical carrier phase offset is the distance from the Antenna Reference Point (ARP) to the antenna phase center.

In the example, the Radius and the Measurement Mark Offset can be set to 0 meter since the measured distance is vertical and calculated at the ARP. The model presented here is made by a user. When you import models from the NGS Table, you'll observe that there is a * in the model name and that you cannot edit the phase center offset.

 

After your models are created, they can be associated to a specific site using the Site Editor (Edit > Site > Occupation tab) or the Rover Editor (Edit > Rover) for a kinematic file.

Antenna Parameters

Presented in the image beside the text are the different parameters involved when measuring the antenna height to the ARP. This is the typical case when using a pole on the field while doing a survey.

 

 

 

Typically this translate into an Antenna model like in the example below:

Article: 000017

Related Products: EZSurv

Last Update: 2018-11-07 20:58:16

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