Skip to main content
Advanced Search
Search Terms
Content Type

Exact Matches
Tag Searches
Date Options
Updated after
Updated before
Created after
Created before

Search Results

309 total results found

New Page

6 Spectrum sensing and cognitive radio

6.5.1 All the channels are available

6 Spectrum sensing and cognitive radio 6.5 Examples

  In such a scenario, the detection threshold is taken to a value of 0 dB (Figure 160) much higher than the sRSS level (average = -82.09 dBm) (Figure 161). Therefore, no victim system has been detected and the WSDs are allowed to transmit in any of the specif...

6.5.2 All the channels are blocked

6 Spectrum sensing and cognitive radio 6.5 Examples

In such a scenario, the detection threshold is taken to a lower value compared to the sRSS and none of the WSDs are transmitting. In SEAMCAT, the Tx power is set to -1000 dBm (Figure 166). The WSD frequency is the same as the victim frequency per event.  Figur...

6.5.3 Some of the channels are blocked and some are available

6 Spectrum sensing and cognitive radio 6.5 Examples

This is a typical example. In such a scenario, the detection threshold is taken to a value of -80 dB (flat over the frequency range). This mean that when considering the sRSS of Figure 168, for some of the events, the sRSS will be above that threshold and ther...

7.1 Introduction

7 Cellular network simulation

Whereas traditional simulation of non-CDMA or non-OFDMA systems is carried out in SEAMCAT by taking two pairs of transmitters-receivers and estimating signals received between them separately (i.e. without any form of feed-back influence), the simulation of ce...

7.2 CDMA overview

7 Cellular network simulation

When simulating CDMA systems, SEAMCAT performs power controlling in a fully loaded system of all the MSs so that the impact from the neighbourhing two tiers is included (inter-cell interference), for victim CDMA systems, and the system level-out the inter-cell...

7.3 OFDMA overview

7 Cellular network simulation

The simulation of OFDMA systems is similar to that of the CDMA systems, except that after the overall two-tiers cellular system structure (incl. wrap-around) is built and populated with mobiles, OFDMA replaces the CDMA power tuning process with an iterative pr...

7.4 TDD vs FDD simulation

7 Cellular network simulation

Note that TDD (Time Division Duplex)/FDD (Frequency Division Duplex) simulations are scenario dependent meaning that the direction of the interferer (UL or DL) to the victim will be studied. In this context, the time dependency is not simulated as it is not im...

Introduction

7 Cellular network simulation 7.5 Cellular network positioning

5 panels characterised the positioning of a cellular system. This panel is the same whether a CDMA (UL/DL) or OFDMA (UL/DL) is simulated.  

7.5.1 System

7 Cellular network simulation 7.5 Cellular network positioning

Initially macro-cellular environment was implemented in SEAMCAT, but with time more flexibility was given to the tool to reproduce various topology options in cellular network (Figure 176). Cell sites are laid out in a hexagonal grid. Sites with omni-direction...

7.5.2 System layout - reference cell selection

7 Cellular network simulation 7.5 Cellular network positioning

A singe cell consists of several MSs connected to their serving BS. The reference cell is a single cell that is surrounded by two tiers of virtual cells to form a 19 cells (or 57 cells for tri-sector deployment) cluster. This cells clutter is then populated wi...

7.5.3 System layout preview

7 Cellular network simulation 7.5 Cellular network positioning

You have the possibility to see a preview of the network you are simulating. You can click on the cell that should be used as reference cell when gathering results. The red cell is the current selection.    Figure 182: System layout preview  

7.5.4 Mobile station

7 Cellular network simulation 7.5 Cellular network positioning

Figure 183: Cellular system – Mobile station GUI      Table 24: Cellular system – Mobile station parameters   Description Symbol Type Unit Comments Antenna height HMS Distribution or Scalar m Height of user terminal in meters. Not...

7.5.5 Base station

7 Cellular network simulation 7.5 Cellular network positioning

Figure 184: Cellular system – Base station GUI     Table 25: Cellular system – Base station parameters Description Symbol Type Unit Comments Antenna height HBS Distribution or Scalar m Distribution used to determine height of BS. ...

7.6.1 Pathloss and Effective Pathloss

7 Cellular network simulation 7.6 CDMA/OFDMA commonalities

Path loss between each user and BS needs to be calculated within the cellular layout. In SEAMCAT, there is a distinction between the raw pathloss and the effective pathloss. The effective pathloss considers the minimum coupling loss (MCL) as defined in 3GPP. T...

7.6.2 Measure interference from entire cluster

7 Cellular network simulation 7.6 CDMA/OFDMA commonalities

For a CDMA network used as an interferering network, when the “Measure interference from entire cluster” button is checked, all the transmitters of the CDMA network are used when simulating the interference (i.e. all 19/57 BS or all UEs in all the cells) to si...

7.6.3 Wrap around feature and implementation

7 Cellular network simulation 7.6 CDMA/OFDMA commonalities

To analyse the behavior of a cellular network without inducing any artifacts due to boundary effects limitations, it is necessary to consider an infinite cellular network. In this case one cannot perform simulation techniques because the network model is not f...

8.1 Introduction

8 CDMA module

SEAMCAT allows the simulation of cellular networks employing Code Division Multiple Access modulation scheme. The specific CDMA standard (e.g. CDMA2000-1X, or W-CDMA/UMTS) can be selected by incorporating the appropriate link level curves into the simulation s...