Diople array element distance

[raju.ratnani]

hi all,

I have a little basic question about definition of antenna element distance for Dipole antenna array.

I wonder that the distance is calculated between middles of patch elements or, from their edges?

Thank you.

 

[zorro]

Normally, distance between elements in an array is taken between their centers.
This is the separation that determines the characteristics of the array.
Regards

Z

 

[raju.ratnani]

and one more thing , if we are talking 0.6 lemda, the value of lemda should be either in free space or lemda in substrate ?
thx

 

[zorro]

Take lambda in propagation medium (i.e. free space) for element spacing and calculation of radiation diagram.
Lambda in substrate is important for element size.
Regards

Z

 

[raju.ratnani]

In case of patch antenna array the element spacing is suggested 0.6 to 0.8 lemda(center to center) but what it should be in case of diople antenna array?

thx

 

[zorro]

Distance is mainly determined by desired characteristics of the array. Nevertheless, element type has some influence.
The most important if these factors is the lack of grating lobes, especially if beam steering is used.
In the case of a linear array of dipoles, there is a difference between collinear and parallel elements.

Z

 

[raju.ratnani]

how should the S11 behaviour of 2*2 array antenna, if it is -12db in case of single dipole antenna(-18db in case of 2*2 array)i mean either it should adding 3dB by something else technique antenna ?

 

[raju.ratnani]

thank you for such good coordination, there are some question raised with time ,
now i want to ask you that in linear array we calculate element between centered to centered in dipole antenna but how can i measure the distance between coplanar like rectangle and square array ? can i measured from edge to edge ?

thanks

 

[zorro]

Relevant distances for far-field patterns are always between centers of elements.
See for example the book "Phased Array Antennas" by Hansen (1st or 2nd Edition) or other books about antennas.
Regards

Z