antenna-theory.com

[Abu Maria.]

hello
the fundamental mode in patch antenna is TM , but how is possible if the field is perpendicular to the patch conductor ? then it is in the plane transverse to the direction of propagation...

look at how Balanis designed the electric field:

[copyrighted link - removed]

balanis chapter 14 , patch antenna , coupling.

thnak u vry much

[bigSteve]

Read these pages:
http://www.antenna-theory.com/antennas/patches/antenna.php

This will give you an idea how the antenna radiates. The video on this page also explains the radiation:
http://www.antenna-theory.com/antennas/patches/patchanalysis.php

[Abu Maria.]

thank u big steve, but I know how a patch antenna radiates
but in the book "Balanis", , and in the study of coupling between patch , balanis put E_field parallel to the surface condcutrice , there is true?
I need to understand the mode of propagation only , thank u big

[bigSteve]

If you read the links I gave you, or watched the video, you would see where the E-field lies that gives rise to the radiation. I don't care what Balanis' book says.

[Abu Maria.]

ok thank you big, but please just tell me why the mode is TM?

[Rfdesign]

Dear Abu Maria
It may be useful for you.
in the Balanis Book in the chapter 14 in the Patch antenna in the Fig14.14 and Fig14.18 there are radiating and non-radiating faces also because of the equation 14-23 is the relation of the TMx mode, this structure has the TM mode.
Read again the 3d Edition of the Balanis book ,chapter 14 pp:828-835.

[Abu Maria.]

thank u very much
then in balanis, he puts Hx equal to zero (Hx=0)
x:direction normal to the surface of the patch
he conisder x the direction of propagation.
then

the direction along the length of the patch is not the direction of propagation.

sorry and thank u