A patch antenna is a type of

antenna Antenna ( antennas or antennae) may refer to: Science and engineering * Antenna (radio), also known as an aerial, a transducer designed to transmit or receive electromagnetic (e.g., TV or radio) waves * Antennae Galaxies, the name of two collid ...

with a low profile, which can be mounted on a surface. It consists of a planar rectangular, circular, triangular, or any geometrical sheet or "patch" of metal, mounted over a larger sheet of metal called a

ground plane In electrical engineering, a ground plane is an electrically conductive surface, usually connected to electrical ground. The term has two different meanings in separate areas of electrical engineering. *In antenna theory, a ground plane is a ...

. They are the original type of microstrip antenna described by Howell in 1972; the two metal sheets together form a resonant piece of

microstrip Microstrip is a type of electrical transmission line which can be fabricated with any technology where a conductor is separated from a ground plane by a dielectric layer known as the substrate. Microstrip lines are used to convey microwave-freque ...

transmission line In electrical engineering, a transmission line is a specialized cable or other structure designed to conduct electromagnetic waves in a contained manner. The term applies when the conductors are long enough that the wave nature of the transmi ...

with a length of approximately one-half

wavelength In physics, the wavelength is the spatial period of a periodic wave—the distance over which the wave's shape repeats. It is the distance between consecutive corresponding points of the same phase on the wave, such as two adjacent crests, tr ...

of the radio waves. The radiation mechanism arises from fringing fields along the radiating edges. The radiation at the edges causes the antenna to act slightly larger electrically than its physical dimensions, so in order for the antenna to be resonant, a length of microstrip transmission line slightly shorter than one-half the wavelength at the frequency is used. The patch antenna is mainly practical at

microwave Microwave is a form of electromagnetic radiation with wavelengths ranging from about one meter to one millimeter corresponding to frequencies between 300 MHz and 300 GHz respectively. Different sources define different frequency ra ...

frequencies, at which wavelengths are short enough that the patches are conveniently small. It is widely used in portable wireless devices because of the ease of fabricating it on

printed circuit board A printed circuit board (PCB; also printed wiring board or PWB) is a medium used in electrical and electronic engineering to connect electronic components to one another in a controlled manner. It takes the form of a laminated sandwich str ...

s. Multiple patch antennas on the same substrate ''(see image)'' called microstrip antennas, can be used to make high gain

array antenna An antenna array (or array antenna) is a set of multiple connected antennas which work together as a single antenna, to transmit or receive radio waves. The individual antennas (called ''elements'') are usually connected to a single receiver o ...

s, and

phased array In antenna theory, a phased array usually means an electronically scanned array, a computer-controlled array of antennas which creates a beam of radio waves that can be electronically steered to point in different directions without moving th ...

s in which the beam can be electronically steered. A variant of the patch antenna commonly used in mobile phones is the shorted patch antenna, or

planar inverted-F antenna An inverted-F antenna is a type of antenna used in wireless communication, mainly at UHF and microwave frequencies. It consists of a monopole antenna running parallel to a ground plane and grounded at one end. The antenna is fed from an inter ...

(PIFA). In this antenna, one corner of the patch (or sometimes one edge) is grounded with a ground pin. This variant has better matching than the standard patch. Another variant of patch antenna with the partially etched ground plane, also known as printed monopole antenna, is a very versatile antenna for dual-band operations.J. R. Panda,

Rakhesh Singh Kshetrimayum Rakhesh Singh Kshetrimayum (born 1978), FIET, SMIEEE is an electrical engineer, educator and Professor in the department of Electronics and Electrical Engineering, Indian Institute of Technology Guwahati. Recently, he was listed in the world' ...

, "A Printed 2.4 GHz/5.8 GHz Dual-band Monopole Antenna with a Protruding Stub in the Ground Plane for WLAN and RFID Applications, " Progress In Electromagnetics Research, vol. 117, pp. 425-434, 2011

References

External links

Patch Antenna Tutorial
EM Talk
Patch Antenna CalculatorThe basics of patch antennas

A Dual-Band Rectangular CPW Folded Slot Antenna for GNSS Applications
{{DEFAULTSORT:Patch Antenna Radio frequency antenna types Microwave technology Antennas (radio)

See also

References

External links