There should be a private section on here for notes... sketchbook.io anyone?

Not really a log but a place for me to dump some research material.

Below material from: http://www.radartutorial.eu/

Phase-increment Calculating

The phase shift Δφ between two successive elements is constant and is called phase-increment. How large is this phase shift to reach a certain value of the beam steering?

A linear arrangement by isotropic radiating elements is looked at.

Die Grafik zeigt mehrere Strahler, die mit einer jeweiligen Phasendifferenz abstrahlen und einer grafischen Herleitung der Phasenverschiebung.

x = d · sin Θs

A radar set works with a wavelength of λ=10 cm.
The distance between the radiating elements is 15 cm.
We can neglect the propagation time differences by the feeder.
The beam steering shall be Θs= 40°.

Task:

Which value shall have to have the phase shifter no. 8 (on the left side) to get this beam steering?

We start with the calculation of the phase-increment.
Because of the trigonometrical function we need a calculator anyway: Δφ =(360°·15 cm/10 cm)·sin(40°) = 347.1°.

This means the radiating element no. 8 needs the phase shift value φ8 = 7 · 347.1 = 2429.7°.

On reason of the periodicity of the sine function a phase shifting of n·360° is the same as 0°. Therefore we can as long as deduct 360° till there is a angle between 0° and 360° of the result. We get therefore for the phase shifter number 8 (left corner) a phase shift value of φ8 = 269.7°.A part of this phase shift is realized by the delay in the feeding line yet.

Higher Resolution Proof of Concept

Working Waterfall Display

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