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Harness the Power of Rectangular Patch Antennas Today!

Antennas, which also go by the name Aerial are crucial components of radar systems, television, and radio systems. These components operate by directing outgoing and incoming radio waves. Antennas are primarily metallic, and they bear a lot of configurations. From the parabolic reflector that technicians use to receive incoming radio waves and satellite signals to the mast-like gadget, they use for television and radio broadcasting.

Antennas are crucial components, especially in this technological era that relies on sending and receiving signals. The Rectangular patch Antenna, which also goes by the name microstrip, has recently become particularly useful. That is because technicians can print this antenna directly onto a PCB (Printed Circuit Board). Due to these features and more, rectangular patch Antennas have become widespread in the mobile phone industry. Moreover, these antennas are easy to fabricate and are not expensive, making them perfect for building high-quality budget gadgets. But are these the only features that make the Rectangular Microstrip Patch Antennas unique? Or do this antenna still have some aces up its sleeve?

Antennas history in a Nutshell

Rectangular Patch Antennas DESIGN

A German Scientist by the name of Heinrich Hertz created the very first antenna back in the 1880s. To develop the antenna, Hertz had to conduct a lot of experiments to try and test the idea of James Clerk Maxwell that states:

–          Visible light is a straightforward example of a broader class of electromagnetic effects that may travel through the air as a series of waves.

While conducting the experiments, Hertz created a working transmitter for these kinds of waves that consist of 2 square, flat metallic plates that link to a specific rod. The rods in the setup, in turn, connect to the closely spaced metal spheres. For the transmitter to function, sparks jump over the distance to a coil of induction attached to the transmitter’s spheres creating an oscillating current in the antenna’s rods. A spark leaping across a chasm in a wire loop signifies the receipt of a wave at a remote location. Hence the antennas were functional.

On the other hand, Guglielmo Marconi is an Italian scientist responsible for the invention of wireless telegraphy. Moreover, this scientist is also responsible for generating a variety of signal-sending and receiving antennas. Furthermore, he is also the reason why we utilize tall antenna designs to deliver low-frequency information.

A scientist named Howel invented patch antennas in 1972. After this discovery, the antenna industry has never been the same again.

Rectangular Patch Antennas

Rectangular patch antennas are a type of antenna we use in a variety of applications, ranging from wireless communications to satellite navigation. These antennas are highly versatile, able to be designed to provide a range of radiation patterns and gain values. A rectangular patch antenna gets its name from its rectangular shape, typically forming by a metallic conductor etched onto a substrate material. This type of antenna is known for having a relatively low profile, which makes it well-suited for use in applications with limited space. Additionally, rectangular patch antennas are often used in applications that require a high level of directivities, such as satellite communications and radar systems.

Rectangular Patch Antenna Radiation Generation

The design of rectangular patch antennas starts with the selection of the patch size and shape, which can be tailored to optimize the radiation pattern and gain of the antenna. The patch is typically constructed from a dielectric material such as FR4 or other PCB materials, which can be coated with a conductive layer such as copper. The patch is then suspended above a ground plane, which is also typically made from a dielectric material. The microstrip line is then connected to the patch via a probe, such as a coaxial cable.

A rectangular Patch Antenna’s radiation tends to be produced by two edges that have two equal slots. However, if the feed location is near the radiating edge’s center, the remaining opposing edges tend not to radiate.

Therefore we can conclude that the radiating patch of a rectangular patch antenna can be created using two slot split by a simple transmission line. Moreover, each of these slots can be well represented using a conductance G and a susceptance X circuit.

Mircostrip Antenna Varieties

Microstrip Antennas bear so many physical parameters. Moreover, they come in varying geometrical dimensions and shapes. Furthermore, you can group these antennas into four different categories:

E-Slot Patch Antennas

The E-slot Patch Antennas is a patch antenna that is E shaped. These types of antennas offer broadband characteristics. Moreover, to efficiently match the feed line to the antenna’s input impedance, technicians must utilize open-ended stubs at the very end of each antenna’s feed line. Moreover, the dimensions of these antennas are 42 mm by 28 mm. Their frequency range lies between 2.40 GHz to around 2.86 GHz, making them efficient at their functionality.

The patch and the feed substrate constitute a dielectric substrate having a thickness of about 6.7 mm and a Dk (dielectric constant of 2.2.

While the antenna’s symmetrical arms produce a dual-band antenna, the asymmetrical arms, on the other hand, produce broadband antennas. As a result, each antenna offers excellent directivity and Gain.

H-Slot Patch Antennas


The H-Slot Patch Antenna gains its name due to the shape of the slots that form after the technician cut three slots off a rectangular Patch Antenna. However, due to this shape, these type of antenna has enhanced:

–          Gain

–          Bandwidth

Moreover, the antenna’s ground plane size is approximately 90 by 100 mm (L by W). Moreover, the dielectric thickness of this antenna is about 3.2 mm.

These antennas operate on one narrow frequency band, which has circular polarization.

U – Slot Patch Antenna

Technicians create these straightforward single-band Patch Antennas by coupling microstrip patch antennas to a rectangular patch. While in the antenna’s patch, technicians carve out a U-slot which offers dual-band functioning. The dimensions of these antennas are 32 by 40 mm (L by W).

Moreover, this patch substrate’s Dk (dielectric constant) lies at around 4.4, while its resonance frequencies are 5.2GHz and 3.6GHz.

To produce dual-band antennas, technicians carve out one U slot. However, they must add another U slot to the patch to make triple-band antennas. Both slots should have satisfactory directivity and Gain values.

S-slot Patch Antennas

S-slot patch antennas are patch antennas with s shape slots cut in them to offer triple band functionality. To control the antenna’s frequency ratio, technicians adjust the s–shaped slot arm. Moreover, these antennas are 115 by 110 (L by W), and their dielectric substrate stands at 1.06.

These types of antennas provide low-frequency ratios and high directivity and Gain.

Feeding Techniques

Rectangular patch antennas can be fed using a variety of techniques. Both non-contacting and contacting techniques can do the trick.

While using the contacting approach, technicians ensure the transfer of RF power occurs via the connecting elements or the microstrip line.

On the other hand, through the utilization of electromagnetic coupling, electricity flows from the connecting line to the antenna radiating patch while using the non-contact approach.

Four feeding methods exist:

–          Coaxial Probe

–          Microstrip line

–          Aperture coupling

–          Proximity coupling

Microstrip line

Patch Antennas

In this method, technicians link a tiny microstrip patch directly to a conducting strip. However, using this feeding method has one significant upside:

–          Technicians can create the flat structure by etching it up on the same substrate to generate a planar structure.

Coaxial Feed

The coaxial connector’s inner conductor extends and connects to the antenna radiating patch. Moreover, the antenna’s outer conductor attaches to the G (ground) plane.

While using this technique, you are going to benefit in the following way:

–          You can place the coaxial feed at any one of the twenty-six locations in the patch to match the input impedance of the antenna.

However, using this method also comes with some cons, which include the following:

–          The design tends to be pretty complex

–          With this feedback mechanism, you gain a narrow bandwidth

Aperture Coupled Feedback

In this feed technique in Rectangular Patch Antennas, the microstrip feed line and the radiating patch are split via the ground. However, they then couple up via a slot in the G plane.

While utilizing this method, you will enjoy the benefit of low cross-polarization since the slot tends to be centered directly below the antenna’s patch. Moreover, due to this feature, technicians can minimize radiation.

However, the disadvantage of using this feeding technique is that these designs are pretty challenging to fabricate because of their multiple layers, which ultimately increase the antenna’s thickness.

Proximity Coupled Feed

The proximity couple feed also goes by the name electromagnetic coupling scheme. In this method, technicians utilize two dielectric substrates and a feed line between the substrates. Moreover, the antenna’s radiating patch should be on the top part of the upper substrate for this technique to function accordingly.

The advantage of using this technique is that you get to eliminate feed radiation. Moreover, this technique yields a high bandwidth, making it efficient.

However, this method also has a disadvantage:

–          These designs are challenging to fabricate due to the dual dielectric layers that require a pitch-perfect alignment for the design to be effective.

Rectangular Patch Antenna Parameters


Directivity is the antenna’s ratio of radiation strength coming from a specific direction to its overall radiation intensity. Moreover, you divide the total amount of power that the antenna radiates by four to determine the average intensity of the radiation. After all this is over, technicians presume the direction taken by the greatest radiation intensity if it wasn’t specified.

Simply put, a non-isotropic source’s directivity tends to be equal to the simple ratio of the:

–          Non-isotropic source radiation intensity in a specific direction, placed over

–          The isotropic source radiation intensity in a particular direction


Another crucial rectangular Patch Antennas parameter that describes how it performs is its Gain. However, you should note that although Gain and directivity tend to have some connection, they are not the same. Gain is a metric that accounts for the antenna’s efficiency and bidirectional capabilities. Directivity, on the other hand, only caters to the bidirectional capabilities of the antenna.

Technicians define Gain as “The intensity ratio in a specific direction to the intensity of the radiation that’d be gained if the accepted power by the patch antennas was radiated isotropically.“

Designing Microstrip Antennas

To develop a rectangular Patch Antenna, technicians must utilize complex formulations to achieve all the details and functionality principles. Moreover, the designing process tends is complicated, and it assumes some specified information which includes:

–          The antenna’s dielectric constant

–          The antenna resonant frequency

–          The substrate’s height

The designing procedure of a rectangular Patch Antenna follows the following steps:

–          Specify the following variables – the dielectric constant, resonant frequency, and the substrate height

–          Determine – W and L where L is half of the free space wavelength dividing it through by the effective dielectric constant of the boards material.

Application Areas of Rectangular Patch Antennas

The Rectangular Patch antennas are most famous due to their robust design and excellent performance. Due to this feature, these antennas have made their way into many industries, and their application areas grow daily.

We can utilize these antennas for military and civilian applications such as missile guidance, remote sensing, direction founding, radar systems, surveillance systems, satellite communication, vehicle collision avoidance systems, MIMO (multiple input and multiple outputs) systems, GPS, television, mobile systems, broadcasting radio, and radio frequency identification.

Satellite and Mobile Communication Applications

Patch Antennas PCB

Small, affordable, and low-profile antennas are necessary for mobile communication. Rectangular Patch antennas satisfy all these specifications making them the perfect fit for this application.

Moreover, while carrying out satellite communication, technicians require polarized radiation patterns. However, you can only achieve these patterns using circular or rectangular patches. Therefore you can work with rectangular Patch Antennas.

Radar Applications

Using radar, you can easily detect moving objects from a far distance. These systems are crucial for military operations.

Radar systems, however, operate on lightweight, low-profile antennas. Therefore, rectangular patch antennas are a perfect fit for this type of application.

GPS Applications

Microstrip patch antennas bear high substrate elements for GPS (global positioning systems) applications. Moreover, these antennas tend to be circularly polarized not linearly polarized, making them efficient in terms of GPS applications.

Radio Frequency Identification

RFID is beneficial in so many areas, for example, in health care, transportation, manufacturing, logistics, and mobile communication. These systems utilize frequencies that are between 5.8 GHz and 30 Hz. Moreover, RFID systems act as transceivers and transponders.

Medical Applications

Microwave radiations are the most efficient approach to generating induced hyperthermia when treating tumors. However, the radiator doctors use for this functionality should be lightweight for maneuverability. Due to these reasons, most technicians utilize rectangular patch antennas for this application.

Benefits of Rectangular Patch Antenna

The benefits of rectangular patch antennas include their low profile, which makes them well-suited for use in applications where there is limited space. They also have a high directivity level, allowing them to focus their signal in a specific direction, making them well-suited for use in applications requiring precise signal targeting. Additionally, rectangular patch antennas are relatively simple and inexpensive to manufacture, which makes them a cost-effective choice for many applications.

More benefits of Rectangular Patch Antennas include:

–          They function perfectly at some microwave frequencies, which traditional antennas don’t support.

–          These antennas are tiny; therefore, they help manufacturers develop small gadgets.

–          They can easily support more than one frequency band (triple, dual)

–          These antennas are robust

–          They are lightweight; hence they account for the generation of lightweight gadgets, which are a significant hit in the market today.

–          Moreover, due to their feeding techniques, these antennas have minimized excitation of undesired modes.

Drawbacks of Rectangular Patch Antennas

Even though Rectangular Patch Antennas are efficient in terms of performance and functionality. They still have some drawbacks, which include:

–          These antennas offer relatively lower bandwidth impedance

–          They also provide lower gains

–          Moreover, these antennas don’t have impeccable power-handling abilities

–          They offer low efficiency because of their conductor and dielectric losses

Simulation Software Programs for Microstrip Patch Antenna

For more efficient designs and optimized Antennas, you should first utilize simulation software to test your concept. Doing so brings in a lot of advantages which include:

–          Lowering the cost of production by cutting costs on fixing errors at later stages

–          Identifying mistakes at an early stage

–          Optimizing your design and so much more

Some simulation software programs that you can utilize to achieve this feat include:


IE3D is an easy-to-use electromagnetic optimization and simulation software that is useful for rectangular microstrip antenna and circuit designs. The IE3D interface incorporates menus and graphics for easy delivery of content. Moreover, the interface also has auto-meshing and utilizes an efficient field solver.

CST Microwave Studio

The CST Microwave Studio software is a Rectangular and square Patch Antenna simulation software for 3D simulations. CST’s MWS enables fast and accurate analysis of HF (higher frequencies) gadgets, for example, antennas, planar, couplers, and filters.


Rectangular Patch Antennas are, without a doubt, a marvel of engineering. Their efficiency, reliability, and performance have made them crucial components in the tech industry. Moreover, technicians are still working on improving this technology over time. Additionally, the utilization of simulation technology takes this technology to a whole new level. Now you can simulate your antenna prototype before developing it, helping you catch errors at early stages and optimize your design.