Circular patch, Array 8 by 1, 28Ghz
I have designed circular patch antenna (single element). I have to create an array of 8 by 1 (Linear array). But i am not sure how to create a corporate feed network for my antenna. Please Help. thank you
Moreover, Normally there is a 50 ohm feed to the Patch, but i have seen that in corporate feed the input impedance to the patch is 100 ohm. Like one in the attached figure
Hi,
It depends where you put the inset feeder. Near the edge of the patch the impedance is high. For square patch about 100 ohms. Once you know your impedance, you use lambda/4 transformers. It's very easy ...
Bye.
Hm.... so if i am using a 100 ohm insert the feed location will change accordingly! :) Thanx
Yes. In fact on you picture the inset feet is too near of the center patch that i doubt that the patch's impedance is 100 ohms. The nearer of the centre the inset feed is , the smaller is the impedance.
Moreover, don't forget that in parallel two impedances of the same value give a one half impedance.
bye.
Thank You. Let me complete my design. If the problem persist, I'll send the model.
Can you guide me what i did wrong in corporate feed. w50,w70 and w100 are 50,70 and 100 ohm Tx lines respectively. Its for 28GHz (wavelength=10.7mm). Separation between patches is lambda/2 (5.35mm). All 70 ohm lines are lambda/4 (2.675mm). substrate height is 0.7mm and Er=6
This is my design
Well,
As i see, you make a mistake : you have a 50 Ohms line which is split into two lines of 70.7 ohms. However 70.7 // 70.7 = 35.35 Ohms. So it's not matched. Furthermore, do you know the impedance of your patch ? Have you compute it ? Or calculate it ? Are you sure that this impedance is 100 Ohms ?
Later.