RFLink Object

The RFLink object can be attached to a Spacecraft for use in radio frequency (RF) analysis between GroundStation objects or other Spacecraft objects. The RFLink object can be used to determine a transmitter or receiver's effective gain, effective isotropically radiated power (EIRP), power, noise, signal to noise ratio (SNR), link margin, and free space path loss (FSPL). You can assign RFLink objects using the = operator. See the Coverage and Contact Analysis Guide for more information.

Available In Editions:

Timing Precision Mode

This page describes functionality in millisecond timing precision mode. Millisecond timing precision mode is deprecated and will be removed in a future release. We recommend that you migrate your Mission Plans to nanosecond timing precision mode.

Name	Description	Attributes
AtmosphericLoss	Represents the losses caused by atmospheric attenuation. If losses due to weather are to be accounted for, they must be included in this value. Used in the received power and transmitter power calculations.	Type: Variable Access: Read/Write Units: dB
Bandwidth	The link bandwidth. Used in the calculation of the signal to noise (C/N) and energy per bit to noise power spectral density ratios (Eb/No), as well in the noise and link margin calculations.	Type: Variable Access: Read/Write Units: MHz
BitRate	Represents the number of bits transmitter per unit time. Used as part of the symbol rate calculation, which in turn is used in the calculation of the energy per bit to noise power spectral density ratio (Eb/No) and the link margin.	Type: Variable Access: Read/Write Units: bps
DeclaredName	The name of the object as declared.	Type: String Access: Read-Only
Frequency	The number of cycles per unit time of the link. Used to obtain the wavelength of the link, which is in turn used to calculate the free space loss and the effective antenna area.	Type: Variable Access: Read/Write Units: MHz
LinkPowerMargin	The margin between the actual received power and the desired reveived power in the link. Used in the calculation of the transmitter power.	Type: Variable Access: Read/Write Units: dB
ModulationType	The method used to vary the characterstic of the link's carrier wave. Used as part of the symbol rate calculation, which in turn is used in the calculation of the energy per bit to noise power spectral density ratio (Eb/No) and the link margin.	Type: String Access: Read/Write
Name	The name displayed for this object in output windows such as views, plots, and reports.	Type: String Access: Read/Write
ObjectId	The unique identifier for the object.	Type: Variable Access: Read-Only
ObjectType	The type of the object.	Type: String Access: Read-Only
PolarizationLoss	Represents the losses caused by polarization mismatch between the receiver and the incoming signal. Used in the received power and transmitter power calculations.	Type: Variable Access: Read/Write Units: dB
Receiver	The sub-object that holds the receiver related parts of the RF link.	Type: RFLinkComponent Access: Read-Only
Transmitter	The sub-object that holds the transmitter related parts of the RF link.	Type: RFLinkComponent Access: Read-Only

Name	Description
ClearSavedStates	Clears previous saved states for this object.
ComputeLinkMargin	Returns the link margin for the link based on the calculated energy per bit to noise power spectral density ratio (Eb/No) and the required energy per bit to noise power spectral density ratio (Eb/No) as determined by the input and inputType arguments. Returns the results in units of dB.
ComputeReceivedPower	Returns the computed power received by the receiver in dB.
ComputeTransmitterPower	Returns the needed transmitter power to achieve the receivers desired power and provide the RFLink's link margin. Returns the result in units of dB.
GetEffectiveAntennaArea	Returns the effective area of the receiver's antenna at the given epoch in square meters.
GetEffectiveReceiverGain	Returns the receiver gain after accounting for the provided antenna efficiency in dB.
GetEffectiveTransmitterGain	Returns the transmitter gain after accounting for the provided antenna efficiency in dB.
GetEIRP	Returns the effective isotropically radiated power in dB. This is calculated in the direction of the receiver.
GetEnergyPerBitToNoisePowerSpectralDensityRatio	Returns the calculated energy per bit to noise spectral density ratio (Eb/No) based on the input setting for the link. This solution is based on the solution from ComputeReceivedPower if the second argument is Calculated, comes from the provided receiver desired received power if the second argument is FromReceiver, and is calculated from the gain to noise temperature ratio (G/T) if the second argument is a numeric value.
GetFreeSpaceLoss	Returns the computed space loss of the link in dB.
GetFromFile	Load the object state from the specified FreeFlyer object file.
GetFromString	Load the object state from the specified string.
GetReceiverNoise	Returns the calculated receiver noise in dB.
GetSignalToNoiseRatio	Returns the signal to noise ratio (C/N) for the power in dB. This solution is based on the solution from ComputeReceivedPower if the second argument is Calculated, comes from the provided receiver desired received power if the second argument is FromReceiver, and is calculated from the gain to noise temperature ratio (G/T) if the second argument is a numeric value.
GetTransmitterNoise	Returns the calculated transmitter noise in dB.
PutToFile	Convert the object state to FreeFlyer object xml and write to a file.
PutToString	Convert the object state to FreeFlyer object xml and return as a string.
ReferenceEquals	Returns 1 if the argument refers to the calling object and 0 otherwise.
Restore	Restore an object's state from a previously saved state.
Save	Save the object's state so that it can be restored later.

RFLink Object

Description

Available In Editions:

Timing Precision Mode