transmitter¶
- transmitter … end_transmitter¶
transmitter ... Antenna Commands ... alternate_frequency <id> <frequency-value> antenna_pattern <pattern-name> antenna_pattern_table ... end_antenna_pattern_table attenuation_model <derived-name> attenuation ... (attenuation is a synonym for attenuation_model) aux_data ... end_aux_data bandwidth <frequency-value> beam_tilt <angle-value> check_terrain_masking <boolean-value> terrain_masking_mode [ terrain_and_horizon | terrain_only | horizon_only ] duty_cycle <real-value> earth_radius_multiplier <value> effective_earth_radius <length-value> frequency <frequency-value> wavelength <length-value> frequency_channels <lower-frequency-value> <step-frequency-value> <upper-frequency-value> frequency_list ... end_frequency_list internal_loss <db-ratio-value> polarization [ horizontal | vertical | slant_45 | slant_135 | left_circular | right_circular | default ] power <power-value> powers ... end_powers propagation_model <derived-name> pulse_compression_ratio <db-ratio-value> pulse_repetition_frequency <frequency-value> pulse_repetition_interval <time-value> pulse_repetition_frequency ... end_pulse_repetition_frequency pulse_repetition_interval ... end_pulse_repetition_interval pulse_repetition_frequencies ... end_pulse_repetition_frequencies pulse_repetition_intervals ... end_pulse_repetition_intervals pulse_width <time-value> use_peak_power <boolean-value> end_transmitter
Overview¶
The transmitter block defines the attributes of an electromagnetic transmitter. Various sensor and communication objects make use of transmitters.
Commands¶
- alternate_frequency <id> <frequency-value>¶
Specifies alternate frequencies. For WSF_RADAR_SENSOR types, random frequencies can also be drawn during simulation initialization via the randomize_radar_frequencies command. Multiple entries with consecutively increasing <id>’s may be entered.
- <id>
An ordered input ID in the range [1,N] for adding multiple alternate frequencies.
- <frequency-value>
The alternate frequency value for the given <id>.
Note
The frequency value is required and has an <id> of 0. The frequency entry must precede all alternate_frequency entries because the alternate frequency list is cleared when the frequency value is parsed.
Note
On WSF_RADAR_SENSOR types with multiple beams, each beam must have an equal number of ‘frequency_id’ inputs.
Note
Currently only used by WSF_RADAR_SENSOR and comm.
- antenna_pattern <pattern-name>¶
Specifies the name of the antenna gain pattern used by the transmitter. The pattern must be defined using the antenna_pattern command.
Default: If neither antenna_pattern or antenna_pattern_table is specified, the antenna gain will assumed to be a constant value of 1 (0 dB).
Note
If both antenna_pattern and antenna_pattern_table are specified, the last one specified is used.
- antenna_pattern_table … end_antenna_pattern_table¶
This command allows the definition of frequency-dependent or polarization- and frequency-dependent antenna gain pattern. Each named antenna pattern must be defined using the antenna_pattern command.
To define a table that is only frequency-dependent
antenna_pattern_table frequency <frequency-value-1> <pattern-name-1> frequency <frequency-value-2> <pattern-name-2> frequency <frequency-value-n> <pattern-name-n> end_antenna_pattern_table
To define a table that is polarization- and frequency-dependent:
antenna_pattern_table polarization default frequency <frequency-value-1> <pattern-name-1> frequency <frequency-value-2> <pattern-name-2> frequency <frequency-value-n> <pattern-name-n> polarization <polarization-type> frequency <frequency-value-1> <pattern-name-1> frequency <frequency-value-n> <pattern-name-n> polarization <polarization-type> frequency <frequency-value-1> <pattern-name-1> end_antenna_pattern_table
When defining a polarization- and frequency-dependent table, the following rules must be noted:
Any ‘frequency’ entry that occurs before the first ‘polarization’ entry is assumed to apply to the ‘default’ polarization.
Any polarization that is not defined will use the definition for the ‘default’ polarization.
A ‘default’ polarization must be defined.
The process for determining gain uses the following algorithm:
If a polarization-dependent table is being used, the polarization of the received signal is used to locate the appropriate polarization-specific set of frequency entries. If there is not a corresponding entry for the polarization of the signal being received, the ‘default’ entry is used.
Frequencies greater than or equal frequency-value-m and less than frequency-value-m+1 will use pattern-name-m
Frequencies less than frequency-value-1 will use pattern-name-1.
Frequencies greater than or equal to frequency-value-n will use pattern-name-n.
Default: If neither antenna_pattern or antenna_pattern_table is specified, the antenna gain will assumed to be a constant value of 1 (0 dB).
Note
If both antenna_pattern and antenna_pattern_table are specified, the last specified one is used.
Note
Entries will be sorted into increasing order of frequency.
- attenuation ….. (attenuation is a synonym for attenuation_model)¶
Specify the attenuation model. See the global command attenuation_model for more information about the available attenuation models and how to configure the models.
Default: none (No attenuation effects)
Note
The end_attenuation[_model] command is optional for the none, blake, models.
- aux_data … end_aux_data¶
Defines application-specific ‘auxiliary data’. See aux_data
Default: No auxiliary data is defined.
- bandwidth <frequency-value>¶
- Specifies the spectral bandwidth of the transmitter. The transmit signals whose frequency is between:
[ frequency - 1/2 bandwidth, frequency + 1/2 bandwidth ]
Default: 0 hz
Note
For frequency-hopping systems, the frequency should be set to the center of the frequency-hopping range, and the bandwidth should be set to encompass the range of frequencies. Note that WSF does not currently model the actual instantaneous frequency hopping.
- beam_tilt <angle-value>¶
This is only to be used when defining systems that employ multiple beams (e.g., when using multiple beams in WSF_RADAR_SENSOR). It specifies the elevation angle of the beam center above the horizontal plane.
Default: If there is an implicitly associated receiver(e.g. as in WSF_RADAR_SENSOR), the default will be the value of beam_tilt from the associated receiver. Zero degrees is assume if there is not an associated receiver, or if beam_tilt was not specified in the associated receiver}}
Note
the antenna_tilt or pitch commands should not be used with this command.
- check_terrain_masking <boolean-value>¶
Toggles the computation of terrain and horizon line of sight. This may be set to ‘off’ to either reduce computation or model sensors and comm devices which do not have line of sight limitations. By default, horizon masking is checked first, followed by a separate terrain masking check if terrain is loaded. The simple horizon masking check assumes a smooth bald spherical Earth and that any object below zero mean sea level is obscured. For subsurface sensors, horizon checking can be disabled by setting the terrain_masking_mode to terrain_only.
Default: on
- terrain_masking_mode [ terrain_and_horizon | terrain_only | horizon_only ]¶
Sets the mode or type of masking checks to perform. By default, both horizon and terrain masking checks are enabled.
Default: terrain_and_horizon
- duty_cycle <real-value>¶
Specifies the transmit duty-cycle for a pulsed transmitter. If entered then this value is multiplied by the peak power entered and used as the average power in any calculations not specifically calling out for peak power.
Default: 1.0
- earth_radius_multiplier <value>¶
- effective_earth_radius <length-value>¶
Specify either the multiplier for Earth’s radius, or the effective earth radius, used to compute the effects of atmospheric refraction of radio-frequency signals.
Default: earth_radius_multiplier 1.33333 (4/3)
Note
The Earth’s radius is considered to be 6366707.019 meters, so the default effective Earth radius will be 8488942.693 meters.
- frequency <frequency-value>¶
- wavelength <length-value>¶
- The center frequency of the radiation emitted by the transmitter. The spectrum of frequencies transmitted will be:
[ frequency - 1/2 bandwidth, frequency + 1/2 bandwidth ]
- wavelength is an alternative mechanism for entering the frequency. The resulting frequency will be computed as:
frequency = speed-of-light / wavelength
Default: None. Either frequency, frequency_channels or frequency_list must be specified. If more that one is specified, the last one specified is used.
Note
For frequency-hopping systems, the frequency should be set to the center of the frequency-hopping range, and the bandwidth should be set to encompass the range of frequencies. Note that WSF does not currently model the actual instantaneous frequency hopping.
- frequency_channels <lower-frequency-value> <step-frequency-value> <upper-frequency-value>¶
Specify alternate frequency channels. For WSF_RADAR_SENSOR types, random frequencies can also be drawn during simulation initialization via the randomize_radar_frequencies command. A list of alternate frequencies will be created from this input based on the channel limits and step size.
- <lower-frequency-value> :
The lower bound of the frequency channel.
- <step-frequency-value> :
The frequency step size for the frequency channel.
- <upper-frequency-value> :
The upper bound of the frequency channel.
Default:: None. Either frequency, frequency_channels or frequency_list must be specified. If more that one is specified, the last one specified is used.
Note
On WSF_RADAR_SENSOR types with multiple beams, the frequency channel size must be the same for each beam.
Note
On WSF_RADAR_SENSOR types the beams frequency will be set automatically to the <lower-frequency-value> unless the randomize_radar_frequencies command is specified.
Note
Currently only used by WSF_RADAR_SENSOR and comm.
- frequency_list .. end_frequency_list¶
Specifies a list of alternate frequencies. For WSF_RADAR_SENSOR types, random frequencies can also be drawn during simulation initialization via the randomize_radar_frequencies command. Multiple entries with consecutively increasing <id>’s may be entered.
frequency_list frequency_id <id> <frequency-value> ... frequency_id <id> <frequency-value> end_frequency_list
- <id>
An ordered input ID in the range [1,N] for adding multiple alternate frequencies.
- <frequency-value>
The alternate frequency value for the given <id>.
Default: None. Either frequency, frequency_channels or frequency_list must be specified. If more that one is specified, the last one specified is used.
Note
On WSF_RADAR_SENSOR types with multiple beams, each beam must have an equal number of ‘frequency_id’ inputs.
Note
Currently only used by WSF_RADAR_SENSOR and comm.
- internal_loss <db-ratio-value>¶
A single number that can be used to model various losses between the transmitter and the antenna.
Default: 0 db
Note
This is a ‘loss factor’ and is typically has a positive ‘dB’ value or a linear value greater than 1.
- polarization [ horizontal | vertical | slant_45 | slant_135 | left_circular | right_circular | default ]¶
Specifies the polarization of the transmitted signal. This is an optional entry that can be used for modeling the effects of polarization mismatch.
Default: default
- power <power-value>¶
Peak power output from the transmitter.
Default: None. Either power or powers must be specified.
- powers … end_powers¶
This command allows the definition of frequency-dependent peak power output from the transmitter.
powers frequency <frequency-value-1> <power-value-1> frequency <frequency-value-2> <power-value-2> ... frequency <frequency-value-n> <power-value-n> end_powers
The process for determining power uses the following algorithm:
Frequencies greater than or equal frequency-value-m and less than frequency-value-m+1 will use power-value-m
Frequencies less than frequency-value-1 will use power-value-1.
Frequencies greater than or equal to frequency-value-n will use power-value-n.
Default: None. Either power or powers must be specified.
Note
Entries will be sorted into increasing order of frequency.
- propagation_model <derived-name>¶
- propagation_model <base-name> …commands… end_propagation_model¶
Specify the propagation model. See global command propagation_model for more information about the available propagation models and how to configure the models.
Default: none (No propagation effects)
- pulse_compression_ratio <db-ratio-value>¶
Specify the gain due to pulse compression/coding techniques.
Default: 0 dB (no pulse compression)
Note
This does not alter the effective radiated power of the transmitted signal. The effects of pulse compression are applied during the reception of the signal. It is defined on the transmitter because that is where the compression/coding actually occurs.
- pulse_repetition_frequency <frequency-value>¶
- pulse_repetition_interval <time-value>¶
Specify the pulse rate or inter-pulse spacing for a pulsed transmitter, using one of the following methods: - The average number pulses per unit second (pulse_repetition_frequency}}. - The average time between the leading edge of the pulses (pulse_repetition_interval).
Default: pulse_repetition_frequency 0 hz
Note
If a non-zero value is specified then a non-zero pulse_width must be specified.
- pulse_repetition_frequencies … end_pulse_repetition_frequencies¶
- pulse_repetition_intervals … pulse_repetition_intervals¶
Specifies a list of the pulse rates or inter-pulse spacings for a pulsed transmitter, using one of the following methods: - The average number pulses per unit second (‘’pulse_repetition_frequencies … end_pulse_repetition_frequencies’’). - The average time between the leading edge of the pulses (‘’pulse_repetition_intervals .. end_pulse_repetition_intervals’’).
pulse_repetition_frequencies prf_id <id> <frequency-value> ... prf_id <id> <frequency-value> end_pulse_repetition_frequencies pulse_repetition_intervals pri_id <id> <time-value> ... pri_id <id> <time-value> end_pulse_repetition_intervals
- <id>
An ordered input ID in the range [1,N] for adding multiple pulse repetition_frequencies.
- <frequency-value>
The pulse repetition frequency value for the given <id>.
- <time-value>
The pulse repetition interval value for the given <id>.
Default: 0 Hz, not defined
Note
If a non-zero value is specified then a non-zero pulse_width must be specified.
- pulse_width <time-value>¶
Specifies the average width of the pulse (in units of time) for a pulsed transmitter.
Default: 0 seconds
Note
If a non-zero value is specified then a non-zero pulse_repetition_frequency or pulse_repetition_interval must be specified.
- use_peak_power <boolean-value>¶
When set to true, toggles this transmitter to use peak power in all applicable internal calculations, and by extension, all resulting interactions predicated upon by this transmitter. When set to false, average power is used instead.
Default: False (average power is used)
See Also¶
Military Specific¶
transmitter electronic_attack ... end_electronic_attack end_transmitter
The transmitter block defines the attributes of an electromagnetic transmitter. Various weapon objects make use of transmitters.
- alternate_frequency <id> <frequency-value>¶
Specifies alternate frequencies that a comm in conjunction with jamming_perception_timeout and jamming_perception_threshold or a WSF_RADAR_SENSOR in conjuction with jamming_perception_timeout and jamming_perception_threshold and the electronic_protect WSF_AGILITY_EFFECT technique in the case that jamming is perceived. For WSF_RADAR_SENSOR types random frequencies can also be drawn during simulation initialization via the randomize_radar_frequencies command. Multiple entries with consecutively increasing <id>’s may be entered.
- electronic_attack … end_electronic_attack¶
Defines the electronic attack capabilities of the transmitter. See electronic_attack.
Default No electronic attack capabilities.
