AVA (antipodal Vivaldi antenna)
Introduction
The Antipodal Vivaldi Antenna (AVA) is a type of planar antenna that has gained popularity due to its high gain, broad bandwidth, and low profile. It was first introduced by J. D. Kraus and C. A. Klein in 1978, but it was not until the 1990s that its full potential was realized. Since then, the AVA has been widely used in various applications, including radar systems, wireless communications, and satellite communications.
The Design of AVA
The AVA is a type of traveling wave antenna that is designed using a tapered structure. It consists of two antipodal tapered arms that are connected by a feeding network. The arms are tapered in such a way that the width of the arms decreases as they move away from the feeding point. This design creates a traveling wave that propagates along the arms and radiates from the open ends.
The feeding network of the AVA consists of a microstrip line that is used to feed the antenna. The microstrip line is usually positioned between the two arms and is designed to match the impedance of the antenna to the impedance of the transmission line.
The geometry of the AVA is such that it has a broadside radiation pattern, which means that the maximum radiation is perpendicular to the plane of the antenna. The radiation pattern is also highly directional, which makes it suitable for applications that require high gain and good directivity.
Advantages of AVA
The AVA has several advantages over other types of planar antennas. One of the most significant advantages is its broad bandwidth. The tapered structure of the AVA allows it to operate over a wide frequency range, making it suitable for use in applications that require high bandwidth.
Another advantage of the AVA is its high gain. The tapered structure of the antenna allows it to achieve a high gain with a relatively low profile. This makes it suitable for use in applications where space is limited.
The AVA is also easy to fabricate using standard printed circuit board (PCB) technology. This makes it a cost-effective option for applications that require large numbers of antennas.
Applications of AVA
The AVA has been used in various applications, including radar systems, wireless communications, and satellite communications.
In radar systems, the AVA is used as an antenna for transmitting and receiving radar signals. The high gain and directional radiation pattern of the AVA make it suitable for use in radar systems that require high resolution and long-range detection.
In wireless communications, the AVA is used as an antenna for transmitting and receiving wireless signals. The broad bandwidth and high gain of the AVA make it suitable for use in wireless systems that require high data rates and long-range communications.
In satellite communications, the AVA is used as an antenna for transmitting and receiving signals between satellites and ground stations. The high gain and directional radiation pattern of the AVA make it suitable for use in satellite systems that require high data rates and long-range communications.
Conclusion
The Antipodal Vivaldi Antenna (AVA) is a type of planar antenna that has gained popularity due to its high gain, broad bandwidth, and low profile. Its unique tapered structure allows it to achieve a high gain with a relatively low profile, making it suitable for applications that require high gain and good directivity in limited space. The AVA has been used in various applications, including radar systems, wireless communications, and satellite communications. Its cost-effectiveness and ease of fabrication using standard PCB technology have made it a popular choice for applications that require large numbers of antennas.