Permanent Solutions - Stability Monitoring
  • You can use GPS to monitor engineering structures, ground subsidence, and geologic faults with sub-cm precision.

If you have a permanent GPS station/network and want regular high accuracy coordinate solutions we can perform the automated analysis for you. Typical applications for this service would be the monitoring of structures such as bridges, dams, and oil platforms. We compute a new daily, weekly, or monthly position (longitude, latitude and height) of your site. You will obtain the updated solutions and the time series that monitor the stability of your structure in the ITRF96 or NAD 83 reference frame. Here is how this works (more questions are addressed below):

(1) Contact us regarding the set-up of such a service (info@gps-solutions.com)

(2) You collect the GPS data and place them on a computer that we can reach electronically

(3) You specify how frequent you require updated solutions (i.e. daily, weekly, monthly, ...)

(4) Every day/week/month we will retrieve your data, compute a solution, and send you the results (including uncertainties) and time series plots

If you are interested in this service here we try to answer a few questions:

How does this service work and what does is do?

Details from where, when and how data are transferred to GPS Solutions Inc. have to be discussed on the phone. We will call you after you emailed us how and when you can be reached.

We begin to retrieve and analyze your data (or you can transfer them to our computer) and send you the results. Our analysis uses the Bernese GPS software and highly accurate IGS orbits. The position time series should display very slow motion of your monuments on the order of a few mm / year.

How much does this cost - how will I be charged?

Cost depends on the number of stations and how often a solutions is computed. Below is our pricing table. All prices are subject to change and assume a minimum contract period of 6 months.

number of sites cost per month
daily solution US $
cost per month
weekly solution US $
1 400 300
2 650
475
3 900 650
4 1100 775
5 1300 900
6 1500 1025
7 1700 1150
8 1800 1225
9 1900 1300
10 2000 1375
>10 add 75 / site add 50 / site

We will invoice the network analysis fee for the first month and a $400 setup fee at the beginning of the service. The setup fee will be credited (reimbursed to the customer) after the first 6-month monitoring period.

How good are the solutions?

Typical position accuracies that are achievable with the Bernese software and IGS orbits are on the order of 2.5 + 2*(baseline-length) * 10exp-9 mm in the horizontal. and about three to five times this large in the vertical. This means that a station within 1000 km from the reference sites can be located to within 4.5 mm in the horizontal and about 20 mm in height.

To achieve these accuracies dual frequency data, geodetic antennas and long, typically 24-hour data files are needed. The accuracy for shorter files or non-geodetic antennas is degraded. Here we show a plot of a typical time series that this solution can provide. The station shown here is about 1000 km from the nearest IGS reference site.

How can I check the quality of the solutions?

For permanent monitoring the best check is the repeatability of the solutions. Deformation is often linear with time and a good straight-line fit to the solutions is an other indicator of precise solutions. In addition, point check comparisons with independent solutions may be conducted.

Are the solutions guaranteed?

If you are not satisfied with the solutions and the service that we provide you can terminate the permanent monitoring service at any time. You will be charged for the monitoring service up to the termination date. If termination occurs before the initial 6-month period you will not be reimbursed the initial setup fee of $400. After the initial 6-month period the setup fee will be reimbursed.

While we make every effort to obtain the highest quality solutions we cannot provide any sort of warranty for the results.

For precise positioning with GPS, it is important to know the exact type of GPS antenna used for data collection. The following link lists all GPS antennas that GPS Solutions has information about.


GPS Antenna Information.












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