Microstrip Patch Antenna Array
Microstrip antennas are used in applications where size,
weight, cost and ease of installation are required. Theseantennas are low-profile and conformable to bothplanar and non-planar surfaces. Antenna characteristics
are also dependent of dielectric parameters.

case only a quarter of given antenna is needed (Fig. 1).
Metallic parts are considered to be perfectlyconducting.

Antenna arrays are used in order to achieve higher gain.
The larger number of antenna elements, the better gainof antenna array is achieved. Antenna arrays are moredemanding for EM simulation than single element
antennas due to their electrical size.
A model of a microstrip patch array is simulated in
WIPL-D Pro (Fig. 1). Analyzed microstrip arrayconsists of 144 elements. A single element is shown in
Fig. 2. The feeding lines are also modeled. Thisantennas intended application is in anti-collision radars.

Figure 2. Element of microstrip array

Operating frequency is 24.2 GHz, which means that
free space wavelength is 12.4 mm. Dielectricparameters are:Figure 1. Quarter of microstrip patch array

We will focus on only one parameter to illustrate theelectrical size of the array:•ε r = 2 .2 + j ⋅ 0•µ r = 1+ j⋅ 0

For parameters given in Tab. 1, we will calculate gain.
The array is about 18 λ by 4.5 λ at this operating
frequency. Computer used for these calculations has
two Intel® Core™2 Quad CPUs (8 cores in total) and
24 GB of RAM.
Table 1. Parameter of analysis

Parameter

Value [mm]Value [numberof wavelengths]

The width of entire the array is approximately fourtimes less than length.

AntQLen107.8~9WIPL-D Simulation

Whole array
length

215.6~ 18•

length of quarter model of antenna (AntQLen)

In WIPL-D Pro antenna arrays can be designed using
convenient built in features. One can use Copy andMove manipulations to build just the basic arrayelement and then easily extend it into an array. Also,(Anti-) Symmetry feature can be used to diminish
memory requirements and simulation time, so in thisRadiation pattern in 3D is shown in Fig. 3 and its
phi-cut, where phi=0, is shown in Fig. 4. Please notethat the theta angle is measured with respect to the xOyplane.

www.wipl-d.com
contactus@wipl-d.com

Number of unknowns, memory requirements, andsimulation time are given in Tab. 2.
Table 2. Analysis characteristics

ModelNo. of unknowns(memory [GB])Time @ 24.2 GHz[min]quarter

23705 (4.5)

20.2

Conclusion

Figure 3. Radiation pattern with antenna array

We saw that usage of WIPL-D Pro advanced features
such as Symmetry and Copy/Move enables easymodeling of structure and simulation using only aquarter of structure, which is very important for
simulation of complex or electrically large structures.
This paper demonstrates that WIPL-D Pro is
successfully used in simulation of large printed arrays,
taking into account all the couplings between arrays
elements. The model is simulated completely
realistically (finite size), whereas many othercompetitor tools would require approximating this arrayas infinite (applying periodic boundary conditions) or
simulating it element-by-element (neglecting coupling
between elements).

Figure 4. Radiation pattern, phi-cut

www.wipl-d.com
contactus@wipl-d.com