atten_map_fast¶
- pycraf.pathprof.atten_map_fast(freq, temperature, pressure, h_tg, h_rg, timepercent, hprof_data, polarization=0, version=16)[source] [edit on github]¶
Calculate attenuation maps using a fast method.
- Parameters
- freq
Quantity
Frequency of radiation [GHz]
- temperature
Quantity
Temperature (K)
- pressure
Quantity
Pressure (hPa)
- h_tg, h_rg
Quantity
Transmitter/receiver heights over ground [m]
- timepercent
Quantity
Time percentage [%] (maximal 50%)
- hprof_datadict, dict-like
Dictionary with height profiles and auxillary maps of dimension
(my, mx)
as calculated withheight_map_data
.- polarizationint, optional
Polarization (default: 0) Allowed values are: 0 - horizontal, 1 - vertical
- versionint, optional
ITU-R Rec. P.452 version. Allowed values are: 14, 16
- freq
- Returns
- resultsdict
Results of the path attenuation calculation. Each entry in the dictionary is a 2D
ndarray
containing the associated value for the map of dimension(my, mx)
. The following entries are contained:L_b0p
- Free-space loss including focussing effects(for p% of time) [dB]
L_bd
- Basic transmission loss associated with diffractionnot exceeded for p% time [dB]; L_bd = L_b0p + L_dp
L_bs
- Tropospheric scatter loss [dB]L_ba
- Ducting/layer reflection loss [dB]L_b
- Complete path propagation loss [dB]L_b_corr
- As L_b but with clutter correction [dB]eps_pt
- Elevation angle of paths w.r.t. Tx [deg]eps_pr
- Elevation angle of paths w.r.t. Rx [deg]d_lt
- Distance to horizon w.r.t. Tx [km]d_lr
- Distance to horizon w.r.t. Rx [km]path_type
- Path type (0 - LoS, 1 - Trans-horizon)
Notes
The diffraction-loss algorithm was changed between ITU-R P.452 version 14 and 15. The former used a Deygout method, the new one is based on a Bullington calculation with correction terms.
In future versions, more entries may be added to the results dictionary.