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SEAMCAT Manual Table of contents
- About this Wiki
- About the STG (SEAMCAT Technical Group)
- About the source code
- Frequently Asked Questions
- How to register on TracTool?
- Tutorial videos
- Known Issues
- Disclaimer
Introduction
Main structural elements of SEAMCAT
Data elements
- SEAMCAT Data types
- Function entry dialog window
- Emissions mask dialog window
- Random distribution dialog window
- Antenna pattern dialog window
- Signal display window
- How to generate a truncated distribution?
Simulation workspace
Creating SEAMCAT scenario
- Simulation scenario and its programming
- Victim link dialog window
- Interfering link dialog window
- CDMA system dialog window
- Sharing and importing scenarios
CDMA module
- CDMA Module Overview
- CDMA Simulation Engine (CDMAE)
- CDMA system dialog window
- CDMA Link level data
- CDMA simulation algorithm
- CDMA input parameters
- CDMA output results
OFDMA module
Cognitive Radio System module
Performing a simulation
- Simulation control settings
- Running a simulation (event generation)
- Calculating probability of interference
Simulation results...
- Producing simulation report
- Logging options and Remote server
- Saving results in .csv format
Library of scenario elements
- SEAMCAT Library
- Antenna elements
- Receiver elements
- Transmitter elements
- CDMA Link level data
- Propagation model plugins
- Post processing plugins
- Setting up environment for programming plugins
- Exporting and importing a library
Special functions
Detailed algorithms
- Calculation of wanted signal (dRSS)
- Calculation of unwanted and blocking signals (iRSS)
- Calculation of overloading (iRSS)
- Calculation of intermodulation signal (iRSS)
- Interference calculation (non-CDMA/non-OFDMA)
- CDMA simulation algorithm
- OFDMA simulation algorithm
Elementary calculations
- Relative location of VR and IT (Simulation Radius)
- Relative location of transceivers within a link
- Calculation of azimuths and elevations (within a link)
- Calculation of azimuths and elevations (IT-VR path)
- Calculation of antenna gains
- Calculation of VR blocking attenuation
- Calculation of the coverage radius of a transmitter
- Calculation of IT power control gain
- Calculation of IT (unwanted) emissions
Propagation models
- Guide to propagation models in SEAMCAT
- How to test propagation model?
- ITU-R P.1546 model
- Extended Hata and Hata-SRD models
- Spherical diffraction model
- Free Space Loss model
- User-defined model (Propagation plug-in)
- JTG5-6 propagation plug-in
- SE42 propagation plug-in
- Longley Rice propagation plug-in
- Winner propagation plug-in
- IEEE 802.11 Model C (modified) plug-in
Reference annexes
- Setting antenna height, pointing azimuth and elevation
- Setting path azimuths in links
- Setting blocking attenuation of victim receiver
- Scenario consistency check
- Error and warning messages
Example Scenarios
Release to be tested by STG
Calculation of blocking attenuation
Blocking attenuation (also might be referred to as selectivity feature) is a function of the frequency difference between interfering transmitter and victim receiver Δf = fit - fvr. It is introduced to enable the evaluation of ability of victim receiver's filtering/selectivity mechanisms to withstand the interference from the full power of an interfering transmitter that is transmitting in an adjacent channel/band.
Three calculation modes are available, according to the way the Blocking function is defined in the scenario:
- Blocking function set as User-defined attenuation function, i.e. the entered function represents the actual receiver filter mask (in dB) - in this case the blocking attenuation value is simply derived from the user-defined function depending on the IT-VR frequency shift as an argument;
- Blocking function is defined in Protection ratio mode, i.e. the function entered by the user corresponds to the required protection ratio (in dB) - in this case the blocking attenuation value is derived using following formula:
- Blocking function is defined in Sensitivity mode, i.e. the entered function represents the absolute maximum interfering power tolerated by the victim receiver (in dBm) - in this case the blocking attenuation value is derived using following formula:
Note that the C/(N+I) value used in the above formulas is taken directly from the interference criteria settings of the Victim Receiver. Therefore users must carefully set this value in the scenario. See further guidance on application of the above formulas here.
How to simulate multiple ACS due to multiple interferers with various bandwidths?
When simulating cellular environment like LTE, the 3GPP standard provides different ACS values depending on the bandwidth of the interferer. For instance, it is known that LTE can support flexible channel bandwidth, 1.4MHz, 3MHz, 5MHz, 10MHz, 15MHz and 20MHz. Therefore, in order to be able to deal with more LTE co-existence scenarios in the future, it is unavoidable to support scenarios with different bandwidth interferers.
SEAMCAT is able to handle such a case. Please read throught the following information on how to do define the workspace in SEAMCAT.
