Transmitter: Basic Properties

Basic properties describe specific input parameters associated with the transmitter model.

Type: Fixed data

Availability: Reports

Name Dimension Type Description
Xmtr Model Unitless Text The transmitter model type. This can be one of ten types: Simple Source Transmitter, Medium Source Transmitter, Comlex Source Transmitter, Multibeam Source Transmitter, Laser Source Transmitter, Plugin Source Transmitter, GPS Satellite Source Transmitter, Simple Retransmitter, Medium Retransmitter, and Complex Retransmitter.
Frequency FrequencyUnit Real Number or Text This is the frequency that the receiver is tuned to or operating at.
Use Spectral Filter Unitless Text The status of the spectral filter feature. If the spectral filter is enabled "True" is returned, otherwise "False" is returned.
Filter - Type Unitless Text The type of filter that is selected (e.g. Butterworth).
Filter - Upper Spectral Limit BandwidthUnit Real Number or Text The selected filter's upper spectral limit. The filter's upper limit on the power spectrum. The bandwidth limit is relative to the carrier frequency (the carrier being at zero Hz), and is specified as a positive value. The upper limit is considered to be a sharp cutoff point and the spectrum is zero beyond the limit.
Filter - Lower Spectral Limit BandwidthUnit Real Number or Text The selected filter's lower spectral limit. The filter's lower limit on the power spectrum. The bandwidth limit is relative to the carrier frequency and is specified as a positive value. The lower limit is considered to be a sharp cutoff point and the spectrum is zero beyond the limit.
Filter - Insertion Loss RatioUnit Real Number or Text The selected filter's insertion loss. This is a fixed signal attenuation in addition to the spectral loss computed by the filter's response characteristics.
Filter - Order Unitless Real Number or Text The selected filter's order. In general, higher order filters have sharper roll-offs at the cutoff frequencies.
Filter - -3dB Cutoff Frequency BandwidthUnit Real Number or Text The selected filter's -3dB (50 percent) filter attenuation response point.
Filter - Ripple RatioUnit Real Number or Text The selected filter's ripple. This value represents the amount of ripple present in the filter pass and stop bands.
Filter - External Filename Unitless Text The external filter filename, if an external filter type is selected.
Auto Scale Bandwidth Unitless Text The status of the source transmitter's auto scale feature. If autoscale is enabled "True" is reported, other "False" is reported. For retransmitter's, "N/A" is always reported.
Bandwidth Type Unitless Text The source transmitter's bandwidth type. This can be one of two values "Asymmetric" or "Symmetric". For retransmitter's, "N/A" is always reported.
Bandwidth BandwidthUnit Real Number or Text Bandwidth is the Receiver Bandwidth.
Bandwidth Upper Limit BandwidthUnit Real Number or Text The source transmitter's upper bandwidth limit. For retransmitter's, "N/A" is always reported.
Bandwidth Lower Limit BandwidthUnit Real Number or Text The source transmitter's lower bandwidth limit. For retransmitter's, "N/A" is always reported.
Mod. Upper Spectral Limit BandwidthUnit Real Number or Text The source transmitter's modulation upper spectral limit. If the power spectral density feature is enabled for the source transmitter, this value will be reported as 15 times the first null frequency. For retransmitter's, "N/A" is always reported.
Mod. Lower Spectral Limit BandwidthUnit Real Number or Text The source transmitter's modulation lower spectral limit. If the power spectral density feature is enabled for the source transmitter, this value will be reported as -15 times the first null frequency. For retransmitter's, "N/A" is always reported.
Use PSD Unitless Text The filter's power spectral density feature. If power spectral density is enabled "True" is reported, other "False" is reported. For retransmitter's, "N/A" is always reported.
WaveLength SmallDistanceUnit Real Number or Text The source transmitter's wavelength. This is equal to the speed of light (2.99792e8 m/s) divided by the source transmitter's frequency.
Number of Beams Unitless Real Number or Text The number of beams modeled by the transmitter. If the transmitter type does not model beams (e.g., Simple Source Transmitter), "N/A" is reported.
EIRP PowerUnit Real Number or Text The effective isotropic radiated power is the product of the transmitter power and the transmitter boresight gain with the inclusion of user-defined post transmit gains and losses.
Gain RatioUnit Real Number or Text Receiver Gain is the antenna gain (in dBi) of the receiver which is dependent on the antenna type used. For medium and laser receiver's this value is a constant defined by the user. For complex and multibeam receiver's, the maximum antenna gain for the selected antenna type or the receiver is reported. The simple receiver model assumes an isotropic antenna and therefore reports the antenna gain as a constant 0.0 dB.
Power PowerUnit Real Number or Text The RF power output of the transmitter as measured at the input to the antenna. This is a user selectable value. For retransmitter's, "N/A" is always reported.
Data Rate DataRate Real Number or Text The data rate of the source transmitter. For retransmitter's, "N/A" is always reported.
Modulation Type Unitless Text The modulation type of the source transmitter. For retransmitter's, "N/A" is always reported.
Gains and Losses RatioUnit Real Number or Text The total post-transmit gains and losses of the transmitter.
Saturated Flux Density PowerFluxDensity Real Number or Text The retransmitter's saturation flux density. This value represents the amplifier's saturation point in terms of the input flux density in dBW per meter squared and is the per carrier flux density for systems supporting multiple carriers per transmitter. For source transmitter's, "N/A" is always reported.
Saturated EIRP PowerUnit Real Number or Text The simple retransmitter's saturated effective isotropic power (EIRP). This value represents the EIRP at the output of the transmit antenna when the amplifier is at its saturated state and is the per carrier EIRP for systems supporting multiple carriers per transmitter. For all other transmitter types, "N/A" is always reported.
Saturated Output Power PowerUnit Real Number or Text The retransmitter's saturated output power. This value represents the RF Power output of the transmitter as measured at the input to the antenna when the amplifier is at its saturated state. For source transmitter's, "N/A" is always reported.
Chips/Bit Unitless Real Number or Text The source transmitter's chips/bit value. This value is used to compute the code division multiple access (CDMA) spreading gain. CDMA spreading gain improves the C/N carrier-to-noise ratio by a factor equal to the spreading gain. For retransmitter's, "N/A" is always reported.
CDMA Spreading Gain RatioUnit Real Number or Text The source transmitter's code division multiple access (CDMA) spreading gain. This value is computed as 10 * log10(chips/bit). For retransmitter's, "N/A" is always reported.
CDMA Gain Select Unitless Text The status of the code division multiple access (CDMA) feature for source transmitter's. If CDMA is enabled "True" is reported, otherwise "False" is reported. For retransmitter's, "N/A" is always reported.
Polarization Unitless Text Polarization shows which polarization type has been selected for the antenna. Polarization is a property of an electromagnetic wave that describes the orientation of the electric field vector with reference to the antenna's orientation. The three basic types of polarization are linear, elliptical and circular. In special cases of linear polarization, the electrical field is aligned vertically or horizontally with reference to the antenna. Circular polarization can be right-handed or left-handed. STK computes the polarization match, which is a quantity between a transmitter and a receiver based on their polarization types, positions, and attitudes. If a receiver or transmitter is of a single-beam type, the Model page for that communications object allows you to select among several polarization types, and, depending on the type selected, to specify one or more parameters. For multi-beam models, polarization is defined in the Modify Antenna Beam window.
Polarization - Vertical Reference Axis Unitless Text Vertical reference axis specifies the axis (X, Y or Z) with respect to which the electrical field is oriented. This is applicable to linear, vertical, horizontal or elliptical polarization. Otherwise N/A is reported.
Polarization - Tilt Angle AngleUnit Real Number or Text Tilt angle is the angle between the vertical reference axis and the x axis of the coordinate system. This is applicable to linear or elliptical polarization. Otherwise "N/A" is reported.
Polarization - Axial Ratio Unitless Real Number or Text Axial ratio is the ratio of the major to the minor axis of the polarization ellipse. This is only applicable to the elliptical polarization type.

STK Programming Interface 11.0.1