Introduction
SEAMCAT (Spectrum Engineering Advanced Monte Carlo Analysis Tool) is a statistical simulation model that uses a method of analysis called Monte Carlo to assess the potential interference between different radiocommunication systems such as broadcasting, point to point, point to multipoint, radar, Mobile networks, aeronautical and satellites.
This ECC Report is intended as a handbook on SEAMCAT for new users; to guide them from installation to carrying out advanced simulations, therefore the users will be refered to as “you”. It is also intended as a reference for more experienced users by providing working guidance on different scenarios and advanced functions.
SEAMCAT is a radio spectrum system oriented software tool which allows you to build your own libraries (such as antennas, spectrum masks, propagation models, radio systems) or use those provided by other users to ease the effort to build complete scenarios for investigation. SEAMCAT is distributed with a predefined set of libraries, so that you do not need to reinvent the wheel every time you have studies to perform.
SEAMCAT is designed so that play/replay feature and plugins can help radio spectrum engineers to understandhow simulations are run or to extend algorithms.
The fundamental concept of SEAMCAT is to provideeasy sharing of radio spectrum compatibility studies (parameters, methods and results) within the CEPT by using a common interface. SEAMCAT is an open source tool and therefore freely available. SEAMCAT is widely used within the CEPT project teams, and also outside the CEPT globally by regulators, industry and academia. Scenarios can be studied, recreated and reconsidered by any of the interested parties using SEAMCAT. The only area for discussion arethe input parameters and the scenarios under investigation. Studies for investigation may cover and are not limited to:
- Sharing and compatibility studies on different equipment operating in the same or adjacent frequency bands;
- Assessing the impact of using different systems transmit and receive masks;
- Evaluation of limits applied e.g. for unwanted emissions, blocking or intermodulation products.
SEAMCAT version 5.0.0 and upward is a tool based on multicore processing allowing fast computation.
You can join the SEAMCAT community (Section 1.8) to contribute to the development of SEAMCAT and its libraries..
This ECC Report provides updated information compared to the material given in ERC Report 68 [7] which specified the original SEAMCAT alorithms.
Methodology
The radio spectrum is a limited resource and can only be used optimally if compatibility is assured between radio systems located in the same or adjacent frequency bands. The important criterion for radio compatibility is the difference between the wanted/desired signal level (victim link system) and any interfering signal levels in the victim link receiver’s input. The most significant interference mechanisms are unwanted emissions from transmitters as well as blocking and intermodulation in the victim link receiver.
There are different approaches [17] to analyse these criteria, such as the Monte Carlo method as provided by SEAMCAT, and the Minimum Coupling Loss (MCL) method.
The Monte Carlo method is a statistical methodology to simulate processes by randomly taking values from a distribution. The term "Monte Carlo method" was coined in the 1940s by physicists working on nuclear weapon projects in the Los Alamos National Laboratory [9]. This approach was used for solving statistical problems and the code name given to the work was Monte Carlo.
A Monte Carlo simulation as used in this report is a statistical technique based upon the consideration of many independent events in time, space and frequency. For each event, or simulation trial, a scenario is built up using a number of different random variables that define the systems to be simulated (e.g. the location of the interferers with respect to the victim, the victim link's wanted signal strength, the channels/frequnecies of the victim and interferer use). If a sufficient number of simulation trials are considered then the probability of a certain event occurring can be evaluated with a high level of accuracy by taking the average result over all trials.
The flexibility in the model and its’ supporting software implementation allow a quick yet reliable consideration of spatial and temporal distributions of the received signals and the resulting statistical probability of interference in a wide variety of scenarios.
Structure of this ECC Report
Section 1 to 2 of this document provides a general overview and description of the software.
Section 3 to 4 guides the beginner, step by step, on how to use SEAMCAT providing details about the software and the graphical interface.
Section 5 to 9 introduces and defines the various radio system input parameters that can be simulated in SEAMCAT.
Section 10 to 12 presents the various tabs, scenarios, event processing and results that are used when performing a spectrum sharing or compatibility study.
Section 13 addresses the library functionaility of SEAMCAT for simulating common transmitters, receivers, masks, antennas, propagation models, etc
Section 14 guides you through the plugin development that is made available to you so that you can develop your own algorithms and libraries compatible with the SEAMCAT run time environment.
ANNEX 1: to ANNEX 27: provides more details of the algorithms, interfaces and principles of sharing studies.
