#DEFINITIONS: -*-sh-*- # # Demonstration and test of a single radio link calculation, using yCalc. # # The link between two satellites is simulated. # # 2012-08-20, Patrick Eriksson Arts2 { INCLUDE "general/general.arts" INCLUDE "general/continua.arts" INCLUDE "general/agendas.arts" INCLUDE "general/planet_earth.arts" # Agenda for scalar gas absorption calculation Copy(abs_xsec_agenda, abs_xsec_agenda__noCIA) # on-the-fly absorption Copy( propmat_clearsky_agenda, propmat_clearsky_agenda__OnTheFly ) # Number of Stokes components to be computed # IndexSet( stokes_dim, 1 ) # Frequency grid # VectorSet( f_grid, [ 0.5e9, 1e9 ] ) # A pressure grid rougly matching 0 to 80 km, in steps of 250. # VectorNLogSpace( p_grid, 321, 1013e2, 1 ) # Definition of species # abs_speciesSet( species= ["H2O-PWR98", "N2-SelfContStandardType", "O2-PWR93"] ) # No line data needed here # abs_lines_per_speciesSetEmpty # Dimensionality of the atmosphere # AtmosphereSet1D # Atmospheric profiles # AtmRawRead( basename = "testdata/tropical" ) # AtmFieldsCalc( t_field, z_field, vmr_field, nlte_field, p_grid, lat_grid, lon_grid, t_field_raw, z_field_raw, vmr_field_raw, nlte_field_raw, atmosphere_dim, 3 ) # Surface altitude MatrixSetConstant( z_surface, 1, 1, 0 ) # No jacobian calculations # jacobianOff # No scattering # cloudboxOff # Check model atmosphere # atmfields_checkedCalc atmgeom_checkedCalc cloudbox_checkedCalc # Propagation path agendas and variables # # transmitter-receiver path Copy( ppath_agenda, ppath_agenda__TransmitterReceiverPath ) # refracted path Copy( ppath_step_agenda, ppath_step_agenda__RefractedPath ) # The reference values are calculated with Thayer's values for k1, k2 and k3: AgendaSet( refr_index_air_agenda ){ Ignore( f_grid ) NumericSet( refr_index_air, 1.0 ) NumericSet( refr_index_air_group, 1.0 ) refr_index_airMicrowavesEarth( k1=77.6e-8, k2=64.8e-8, k3=3.776e-3 ) } NumericSet( ppath_lmax, 10e3 ) NumericSet( ppath_lraytrace, 100 ) # Radiative transfer agendas and variables # Copy( iy_transmitter_agenda, iy_transmitter_agenda__UnitUnpolIntensity ) AgendaSet( iy_main_agenda ){ Ignore( iy_unit ) Ignore( rte_los ) Ignore( nlte_field ) Ignore( diy_dx ) Ignore( iy_id ) iyRadioLink( defocus_method = 2, defocus_shift = 1e-3 ) } # Sensor/receiver and transmitter # MatrixSet( sensor_pos, [ 600e3 ] ) MatrixSet( sensor_los, [ 0 ] ) # Dummy value MatrixSet( transmitter_pos, [ 600e3, 47.8 ] ) # sensorOff sensor_checkedCalc # Auxilary variables # # These are the ones that can be obtained by yCalc. # ArrayOfStringSet( iy_aux_vars, [ "Bending angle", "Extra path delay", "Impact parameter" ] ) # Expected results # VectorCreate( yREFERENCE ) NumericCreate( bending_angleREFERENCE ) NumericCreate( extra_pdREFERENCE ) NumericCreate( impact_parREFERENCE ) # # Values set 2013-10-07, on Patrick's desktop (Ubunt 13.04) VectorSet( yREFERENCE, [1.07137e-15, 1.0652e-15 ] ) NumericSet( bending_angleREFERENCE, 0.377976 ) NumericSet( extra_pdREFERENCE, 259.05e-09 ) NumericSet( impact_parREFERENCE, 6.38905e+06 ) # # Free space, defocusing and atmospheric loss part of y, and no need to check # those terms abs_xsec_agenda_checkedCalc propmat_clearsky_agenda_checkedCalc # Calculate and check iy # yCalc # #Print(y) #Print(y_aux) # Compare( y, yREFERENCE, 2e-17 ) # Bending angle # VectorCreate( vdummy ) NumericCreate( bending_angle ) Extract( vdummy, y_aux, 0 ) Extract( bending_angle, vdummy, 0 ) Compare( bending_angle, bending_angleREFERENCE, 1e-4 ) # Extra path delay # NumericCreate( extra_pd ) Extract( vdummy, y_aux, 1 ) Extract( extra_pd, vdummy, 0 ) Compare( extra_pd, extra_pdREFERENCE, 1e-9 ) # Impact parameter # NumericCreate( impact_par ) Extract( vdummy, y_aux, 2 ) Extract( impact_par, vdummy, 0 ) Compare( impact_par, impact_parREFERENCE, 5 ) }