A11.6 ANTENNA PATTERNS DEFINITION

Figure 419: Antenna pattern identication dialog box


Table 72: Description of the Antenna pattern user interface in SEAMCAT


Description

Symbol

Type

Unit

Comments

Library

-

Library

-

Allows importing/exporting of antennas from/to the library to/from the workspace

Name: name of the Antenna

 


 


Description: comments on the antenna

 


 


Antenna peak gain

gmax

Scalar

dBi

Describes peak antenna gain, i.e. gain in the direction of maximum radiation (main lobe)

Horizontal patterns: Horizontal normalised antenna pattern

gH (φ)

Function (X,Y)

dB/deg

Defined by pairs (φ, gH(φ)), where φ (deg, range 0...+360) describes the angular offset in horizontal plane with relation to the direction of maximum radiation, and gH(φ) describes the relative gain, related to the antenna maximum peak gain.

Note: gH(φ) values should be negative.

Note: The antenna pattern range definition for CDMA has been modified to match the antenna patterns specified by 3GPP (deg, range -180...+180)

Vertical patterns: Vertical normalised antenna pattern

gV (φ)

Function (X,Y)

dB/deg

Input angle values between –90O and 90O.

For the gain, only input negative values relative to the Antenna peak gain.

Spherical patterns: Spherical normalised antenna pattern


 

It describes the antenna spherical radiation pattern, defined by pairs (Φ, ), where Φ (deg, range 0...+180) describes the spherical angle, and describes the relative gain, related to the antenna maximum peak gain. values are negative and relative to the Antenna peak gain:




 To define the horizontal, vertical or spherical antenna patterns, the dialogue window is similar to those used to enter the function dialogue windows. However an important difference is that antenna pattern dialogue windows do not allow setting Constant values, and they have two displays to present the entered data - the usual XY plane, and the Polar display. These are illustrated by two respective pictures below.

 

Figure 420: Antenna pattern dialog box


 

Figure 421: Defining antenna pattern using XY coordinates system


Figure 422: Defining antenna pattern using Polar coordinates system


By default all antennas have 0 dBi gain and are non-directional, i.e. no associated directivity pattern. The antenna pattern can be defined by modifying the antenna gain and activating one or more of radiation patterns depending on the requirements of the scenario. For example, it may be sufficient to activate only the horizontal pattern, but if the vertical discrimination is important in the scenario, both vertical and horizontal patterns could be activated.

 

Figure 423: Horizontal, vertical and Spehrical antenna pattern convention