TETRA Coverage with Monte Carlo Analysis

Perform traffic simulation and export a report using Monte Carlo analysis for trans-European trunked radio (TETRA).

TETRA

TETRA is a European radio standard for professional mobile radio and two-way transceiver. The primary purpose of this type of system is efficiency. A large number of people can carry many conversations over only a few distinct frequencies. Used by government agencies, emergency services, rail transport staff, transport services, and military to provide two-way communication. Both point-to-point and point-to-multipoint transfer can be used.

Motivation for a Monte Carlo Analysis

In this example, a traffic simulation report is generated using the Monte Carlo approach. A Monte Carlo analysis helps to evaluate the numbers of served, blocked, and not-assigned mobiles (users) for each application and each cell. For radio network planning, different types of simulations are available. Monte Carlo simulations use randomly distributed users, which are generated according to location-dependent traffic definitions.

Model Type

This is an example of a TETRA network planning project in a rural/suburban scenario. The geometry is described by topography (elevation) and clutter (land usage), see Figure 1.


Figure 1. A Clutter (morpho) database describing the geometry.

Sites and Antennas

Six sites are distributed throughout the given area. Five sites have three sector antennas each, while one site has one isotropic radiator.
Tip: Click Project > Edit Project Parameter and click the Sites tab to view the sites, antenna patterns, and carrier frequencies.

Air Interface

The air interface is defined by a TETRA wireless standard (.wst) file. TETRA uses TDMA with four user channels on one radio carrier and 25 kHz spacing between carriers. Frequency division duplex (FDD) separation between uplink and downlink is set to 10 MHz.

Tip: Click Project > Edit Project Parameter and click the Air Interface tab to view the carriers and transmission modes.

A list of different modulation and coding schemes are added to this interface. Click Transmission Modes on the Air Interface tab.

Computational Method

The dominant path model (DPM) computation method is selected. This method focuses on the most relevant path in 3D, which can be more accurate than an empirical method or a 2D method.

Tip: Click Project > Edit Project Parameter and click the Computation tab to change the model.

Results

Propagation results show at every location the power received from each transmitting antenna. Results are calculated for a single prediction plane at 1.5 m height.

For all modulation and coding schemes, the network simulation calculates the following:
  • cell area
  • site area
  • maximum data rate
  • maximum throughput for both uplink and downlink

Network results also include the Monte Carlo report arranged in tabular format (10 snaps and their average) evaluated for 16 cells. It also includes a histogram for cell load, noise rise, and throughput for downlink and uplink. As an example, a snippet of the Monte Carlo report is shown in Figure 2.



Figure 2. A snippet of a Monte Carlo report.