About Bearing cycle, Meas. Time and Cycle Time

In a smart antenna like the automatic DF Antenna, there are several elements of antenna arrays, an omnidirectional reference antenna, four phase shifters, a summing stage and a switch matrix.

The SignalShark controls and synchronizes the switch matrix with its extremely fast internal measurement unit.

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Description of the bearing cycle

A complete bearing cycle consists of several measurement steps. During each bearing cycle the omnidirectional channel power and the spectrum are measured.

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Step 1

The level of the omnidirectional element and the level of the antenna element 1 shifted four times in phase are measured. With this, SignalShark determines the magnitude and phase of the covariance between antenna element 1 and the omnidirectional reference element.

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Step 2 to 8

The measurement in step 1 will be repeated for every antenna element.

A measured covariance vector with a complex covariance value for each antenna element is the interim result which is later on used to calculate the bearings.

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Step 9

The omnidirectional channel power and the spectrum are measured.

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Cycle Time as a result of Meas. Time setting

The duration of a single measurement step is the result of the measurement time and some delay time for switching.

The cycle time consists of:

 

The minimum cycle time depends also on the CBW.

In general: Broader CBWs allow shorter cycle times down to 1.2 ms

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