Optimization, Urban, Antenna Adjustment

Optimize the azimuth angle of the tilt of a base-station antenna.

Optimization Overview

During the installation of new radio networks, it is often difficult to find the optimum azimuth and tilt of every base-station sector antenna. With OptMan, you can find the best radio coverage by adjusting azimuth and tilt of a given set of antennas and sites. First, define a radio-planning project with ProMan, including all sites and antennas. Based on any specified network-planning result type, for example, data rate, signal level, interference level, or similar and corresponding optimization target definitions, OptMan finds the best antenna azimuths and tilts to fulfill these specified targets or approach the defined targets as close as possible.

Model Type

The ProMan project is an example of a network planning project for an urban scenario.

Sites and Antennas

The ProMan project has three sites with a total of five sector antennas, see Figure 1. The Site 1 antennas are located at a height of 15 m and the other two sites at 5 m. All operate on a single carrier frequency of 2120 MHz.
Tip: Click Project > Edit Project Parameter and click the Sites tab to view the sites and antennas.


Figure 1. Urban database with three antenna sites in ProMan.

In OptMan, the antennas (transceivers) are listed, as shown in Figure 2. This is the list before optimization.



Figure 2. Transceiver list in OptMan.

At the beginning of the optimization, the antennas to be varied have the check mark Consider for Optimization in the settings at the bottom of the list, and they have the green dot in the ID column.

Optimization Target

The optimization target is to achieve a signal-to-noise-and-interference ratio of at least 5 dB in the entire computational area.
Tip: Click Project > Parameter and click the Target tab to select the optimization target.
The antennas all use the same carrier, which would lead to significant interference.
Tip: If ProMan fails to start, confirm the path in Project > Local Settings.
During the optimization the optimization, chart shown in Figure 3 reports the success rate of the individual runs.


Figure 3. Optimization chart.

Results

The optimum is achieved when the antennas at site 2 and site 3 point away from site 1. This is seen in the updated angles for azimuth in Figure 4.


Figure 4. Optimization results.
Even after optimization, the SNIR plot (Figure 5) still shows large blue areas where the SNIR is below 5 dB. This is mainly because the three-sector antennas of Site 1 are on the same carrier and interfere with each other. The optimization of the azimuths of the two other antennas was successful.


Figure 5. Best SNIR result for QPSK modulation.