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Coverage and Propagation Models. Coverage. Link budget. Propagation Models. Ten propagation models are supported: - ITU-R P.526-6 (Detailed terrain) - DETVAG 90/FOA (Detailed terrain) - ITU-R P.370-7 - Longley-Rice - Okumura- Hata /COST-231 - Hata - COST-231 - Walfish - Ikegami
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Coverage and Propagation Models WRAP 0860G
Coverage WRAP 0860G
Link budget WRAP 0860G
Propagation Models • Ten propagation models are supported: • - ITU-R P.526-6 (Detailed terrain) • - DETVAG 90/FOA (Detailed terrain) • - ITU-R P.370-7 • - Longley-Rice • - Okumura-Hata/COST-231 - Hata • - COST-231 - Walfish - Ikegami • - ITU-R P.452-9 • - ITU-R P.619 • - Free Space • - CRC (Detailed terrain), by special licensing only • Attenuation due to atmospheric gases can be included (ITU-R P.676-2 for terrestrial, P.618-6 for space) • HF Planning with ITS HF software: • -VOACAP/ICEPAC/REC533 (point-to-point) • -VOAAREA/ICEAREA/RECAREA (point-to-area) WRAP 0860G
Propagation mechanisms WRAP 0860G
Propagation Models WRAP 0860G
Propagation Models WRAP 0860G
Propagation Models WRAP 0860G
Propagation Models Table 4.1: Default settings for Detvag-90/FOI propagation model (Quick tab, Low/High accuracy) WRAP 0860G
Propagation Models WRAP 0860G
Coverage • Single transmitter coverage or Multiple transmitter coverage WRAP 0860G
Selectablecalculations (Single station) • Field strength [dBµV/m] • Power flux density [dBW/m2] • Signal strength[dBµV] • Received power [dBm] • Transmission loss [dB] • Clearance [%] • S/I [dB] • Required antenna height [m] • Terrain clearance angle [º] • Neighbour cells, noise & interference limited • Adjacent cell coverage WRAP 0860G
Selectablecalculations (Multiple stations) • Field strength [dBµV/m] • Power flux density [dBW/m2] • Signal strength[dBµV] • Received power [dBm] • Best server, noise limited or interference limited • No of servers, noise limited or interference limited • Maximum clearance, minimum clearance [%] • Maximum required antenna height, minimum required antenna height [m] • Composite coverage, S/I [dB] • Number of interferers • Worst interferer WRAP 0860G
Best server • Best Server, noise limited • maximum signal of all stations in the calculation • signal greater than or equal to the receiver sensitivity plus margin • Best Server, interference limited • maximum SIR of all stations in the calculation • signal greater than or equal to the receiver sensitivity plus margin • SIR greater than or equal to the receiver required SIR plus margin WRAP 0860G
Number of servers • Number of Servers, noise limited • signal greater than or equal to the receiver sensitivity plus margin • Number of Servers, interference limited • signal greater than or equal to the receiver sensitivity plus margin • SIR greater than or equal to the receiver required SIR plus margin WRAP 0860G
Clearance • Maximum clearance calculates the clearance from all stations to the antenna at each point and then displays the value which fulfils the criterion for one of the stations. [%] • Minimum clearance calculates the clearance from all stations to the antenna at each point and then displays the value which fulfils the criterion for all of the stations.[%] WRAP 0860G
Required antenna height • Minimum required antenna height gives the required antenna height to fulfil the clearance criterion from all of the involved stations • Maximum required antenna height gives the required antenna height to fulfil the clearance criterion from one of the involved stations WRAP 0860G
Probability calculations • Normally the calculation results are the local mean values, which are the direct output from most of the propagation models. If the Probability check box is checked, the result is adjusted based on the assumption that the signal has a log-normal probability density function. All probability calculations are performed for the contour probability (and not the area probability). • Standard deviation can be fixed or set by the software (normally 8.3 dB) WRAP 0860G
Probability calculations • Fixed level • Calculation of the probability that a user-defined level achieves. The result can be plotted for different percentages but the level is fixed. • Fixed probability • Calculation of the result levels for a given probability. The result is then plotted for different levels but with fixed probability. WRAP 0860G
A three-level result Long-Lat grid Relief background Radio station Result Presentation WRAP 0860G
Resolution WRAP 0860G
Interference limited coverage • It is possible to select different propagation models for the wanted and interfering signal • Applies for the following calculations • S/I (single station) • Interference limited best server (multi-station) • Interference limited No. of servers (multi-station) • Composite S/I (multi-station) • Number of interferers (multi-station) • Worst interferer (multi-station) WRAP 0860G
Population coverage • The total • number of population that is covered with a certain field strength, received power level etc. • percentage coverage of the total population in a defined calculation area can be calculated. • Requires a database in the appropriate format, with information on the number of inhabitants within a certain square area. WRAP 0860G