Doppler Direction Finders Exhibit Excellent Performance Over Wide Temperature Range
Recently, a customer questioned us on our direction finder’s bearing stability over temperature. Over the years we’ve made some significant improvements in our summing unit so we thought it would be a good time to test the temperature performance of the direction finder.
To perform the test, we mounted a fixed site (8 antenna) summing unit in our thermal chamber. We then connected our antenna simulator to the summing unit and connected the summing unit to a DDF7001 direction finding processor (see Figure 1).
![](https://dopsys.com/wp-content/uploads/2021/07/image-1.png)
The photos below show the summing unit mounted in the thermal chamber.
![](https://dopsys.com/wp-content/uploads/2021/07/image-4.png)
Using the MPT User Interface software, at each temperature, we collected 200 data points and averaged the results. The table below lists the results.
![](https://dopsys.com/wp-content/uploads/2021/07/image-6.png)
Over the temperature range of -20 °C to 60 °C the bearing was stable to within 0.6 degrees.