EAG (Explicit array gain)

Explicit array gain (EAG) is a concept used to describe the increase in signal strength that can be achieved by combining multiple antenna elements in an array. An array is a group of two or more antennas that are positioned close to each other and are used to transmit or receive signals. By combining the signals received by each antenna element, an array can effectively amplify the signal strength, which leads to improved communication performance.

EAG is a fundamental parameter that is used to evaluate the performance of antenna arrays. It is commonly used in wireless communication systems, such as cellular networks, radar systems, and satellite communication systems, to measure the signal gain achieved by an array of antennas. The EAG of an antenna array is typically expressed in decibels (dB) and is defined as the ratio of the signal power received by the antenna array to the signal power received by a single antenna element.

The EAG of an antenna array can be calculated using the following formula:

EAG = 10 log10(N)

Where N is the number of antenna elements in the array. This formula assumes that the antenna elements are identical and are positioned at equal distances from each other. The EAG can be used to compare different antenna arrays and to evaluate the performance of an array under different operating conditions.

There are several factors that can affect the EAG of an antenna array, including the spacing between the antenna elements, the polarization of the antenna elements, and the directionality of the antennas. The spacing between the antenna elements is an important factor that affects the EAG because it determines the level of interference between the antenna elements. If the antenna elements are spaced too close together, they will interfere with each other and reduce the overall performance of the array. On the other hand, if the antenna elements are spaced too far apart, the array will not be able to achieve the desired level of signal gain.

The polarization of the antenna elements is also an important factor that affects the EAG of an array. The polarization of an antenna refers to the direction of the electric field in the signal. There are two main types of polarization: linear polarization and circular polarization. Linear polarization refers to the electric field in the signal being in a straight line, while circular polarization refers to the electric field rotating in a circular pattern. When the antenna elements in an array are polarized in the same direction, the EAG is maximized. However, if the polarization of the antenna elements is not aligned, the EAG is reduced.

The directionality of the antennas in the array is also an important factor that affects the EAG. Antennas can be either directional or omnidirectional. Directional antennas are designed to transmit or receive signals in a specific direction, while omnidirectional antennas transmit or receive signals in all directions. If the antenna elements in an array are directional, they can be aligned to achieve a higher EAG. However, if the antenna elements are omnidirectional, the EAG will be lower because the array cannot focus the signal in a specific direction.

In addition to these factors, there are other considerations that must be taken into account when designing an antenna array. For example, the size and weight of the array must be considered, as well as the cost of manufacturing the array. The materials used in the construction of the array can also affect its performance, as different materials have different electrical properties that can affect the signal strength.

Overall, EAG is an important parameter that is used to evaluate the performance of antenna arrays. By combining multiple antenna elements in an array, the signal strength can be amplified, which leads to improved communication performance. The EAG of an antenna array is affected by several factors, including the spacing between the antenna elements, the polarization of the antenna elements, and the directionality of the antennas. When designing an antenna array,