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).

The photos below show the summing unit mounted in the thermal chamber.

Using the MPT User Interface software, at each temperature, we collected 200 data points and averaged the results.  The table below lists the results.

Over the temperature range of -20 °C to 60 °C the bearing was stable to within 0.6 degrees.