CHAPTER
MICROSTRIP PATCH ANTENNA
In this particular section, an release to the Microstrip Patch Antenna is followed by its benefits and drawbacks. Following, some feed modeling methods are talked about. Last but not least, a detailed explanation of Microstrip patch antenna analysis and its concept are discussed, and also the working mechanism is described.
Arrival
Along with microwave and mm wave frequencies, Communication can be greatly described as the transfer of data from one point to another. A communication system is normally needed when the data is to be disseminated over the range. The exchange of data within the communication system is generally accomplished by superimposing or modulating the data onto an electromagnetic wave which acts as a carrier for the data signal. At the desired destination, the modulated carrier is then received and the original data signal can be retrieved by demodulation.
Throughout the years, innovative strategies have been designed for this process utilizing electromagnetic carrier waves operating at radio frequencies. In today’s modern communication sector, antennas are the most important components required to create a communication link. Through the a long time, microstrip patch antenna structures are the most common option used to realize mm wave monolithic integrated circuits for microwave, radar and communication purposes. The shape and operating mode of the patch are chosen, designs become very flexible in terms of operating frequency, polarization, pattern and impedance.
In its most primary form, a Microstrip patch antenna consists of a radiating patch on either side of a dielectric substrate which has a ground plane on the opposite side as shown.
In order to alter analysis and performance prediction, the patch is mostly sq., rectangular, circular, triangular, elliptical or another common form as shown in Figure three.2. For an oblong patch, the length L of the patch is typically zero.333 λ0wherever λ0 is that the free-space wavelength. The patch is chosen to be terribly skinny specified t <<λ0 (where t is that the patch thickness). the peak h of the stuff substrate is typically zero.003λ0 ≤h≤ zero.05λ0. The stuff constant of the substrate (εr) is usually within the vary two.2 ≤ εr≤ 12. The figure three below shows the common shapes of microstrip patch parts.
Microstrip patch antennas radiate primarily thanks to the fringing fields between the patch edge and also the ground plane. permanently antenna performance, a thick dielectric substrate having a low dielectric constant is fascinating since this provides higher efficiency, larger bandwidth and higher radiation. However, such a configuration results in a bigger antenna size. so as to design a compact Microstrip patch antenna higher dielectric constants should be used that area unit less economical andlead to narrower bandwidth. hence a compromise must be reached between antenna dimensions and antenna performance.
Benefits and Drawbacks
Microstrip patch antennas are increasing in quality to be used in wireless applications thanks to their low-profile structure. thus they're very compatible for embedded antennas in handheld wireless devices like cellular phones, pagers etc... The measuring and communication antennas on missiles have to be compelled to be thin and conformal and are typically Microstrip patch antennas. Another area where they have been used successfully is in Satellite communication.
• Light weight and low volume.
•
Low profile planar
configuration which can be easily made conformal to host surface.
•
Low fabrication cost, hence
can be manufactured in large quantities.
• Supports both, linear as well as circular
polarization.
•
Can be easily integrated
with microwave integrated circuits (MICs).
• Capable of dual and triple frequency operations.
• Mechanically robust when mounted on rigid
surfaces.
Microstrip patch
antennas suffer from a number of disadvantages as compared to conventional antennas. Some of the major
disadvantages discussed below:
• Narrow bandwidth.
• Low efficiency.
• Low Gain.
• Extraneous radiation from feeds and junctions.
• Poor end fire radiator except tapered slot
antennas.
• Low power handling capacity.
• Surface wave excitation.
Feed Methods
Microstrip patch antennas will be fed by a spread of strategies. These strategies can be classified into two categories- contacting and non-contacting. within the contacting technique, the RF power is fed on to the radiating patch employing a connecting component like a microstrip line. within the non-contacting theme, electromagnetic field coupling is done to transfer power between the microstrip line and therefore the diverging patch. The four most well-liked feed techniques used ar the microstrip line, coaxial probe (both contacting schemes), aperture coupling and proximity coupling (both non-contacting schemes).
