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Satellite Link Budget Analyzer

Analyze link budgets for satellite communications

Description

The Satellite Link Budget Analyzer app enables you to analyze link budgets for satellite communications.

Using the app, you can:

  • Analyze link budgets by specifying inputs properties related to

    • Location, transmitter, and receiver characteristics for satellites and ground stations

    • Atmospheric conditions for links

  • Design a satellite communications link to meet a minimum link margin requirement

  • Have insight into intermediate link budget computations

  • Calculate, compare, and visualize results across a sweep of multiple parametrized design constraints

For more information, see Get Started with Satellite Link Budget Analyzer App.

Default satellite link budget app session window, showing the budget analyzer tab

Open the Satellite Link Budget Analyzer App

MATLAB® Toolstrip: On the Apps tab, under Signal Processing and Communications, click the app icon. Satellite Link Budget Analyzer button

MATLAB Command Prompt: Enter satelliteLinkBudgetAnalyzer.

Examples

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This example shows the default configuration that appears when you open the Satellite Link Budget Analyzer app. The displayed results and plots analyze the default satellite communications link.

The upper left area of the app window shows the Link Canvas tab on top with this default configuration:

  • Link L1 is an uplink connecting ground station G1 to satellite S1

  • Link L3 is a crosslink connecting satellite S3 to satellite S4

  • Link L2 is a downlink connecting satellite S2 to ground station G2

The lower left area of the app window shows the Ground Station, Link, and Satellite tabs. In these tabs you can adjust property settings for each entity in the configured links. To view or adjust the properties settings of an entity, bring it into focus by selecting it in the Link Canvas tab.

The center area of the app window shows the computed link budget results in the Link Budget tab.

The right area of the app window shows these plots:

  • Free-space path loss for links L1, L2, and L3 in the upper-right area.

  • Link margins for links L1, L2, and L3 in separate tabbed plots in the lower-right area.

Configure the Satellite Link Budget Analyzer app to analyze satellite communications link availability through the propagation loss model defined in Recommendation ITU-R P.618-13. Load the AvailabilityAnalysis-P618.mat saved session to configure the app for the P.618 availability analysis. This example uses the model and API provided by the P.618 Recommendation. For details on the P.618 propagation loss model, see Earth-Space Propagation Losses. Before configuring the app for the P-618 availability analysis, download and unpack the ITURDigitalMaps.tar.gz file to a directory that is on the MATLAB path.

Configure Satellite Link Budget Analyzer App

Open the Satellite Link Budget Analyzer app. These figures show the default configuration on the Budget Analyzer and Customize Input/Output tabs.

Click Open on the Budget Analyzer tab, and then open the AvailabilityAnalysis-P618.mat saved session file from the working directory of this example.

Opening the saved AvailabilityAnalysis-P618.mat session updates the app configuration by adding new properties, adjusting formulas for results, and simplifying the workflow by removing links and computations not relevant to this analysis scenario.

After the saved session loads, the Budget Analyzer tab shows the configuration updates. On the Budget Analyzer tab,

  • Analyze shows Auto Analyze not selected.

  • Select Links shows that only link L1 is selected. The analysis in this example requires only the uplink path (link L1).Computation of results for links L2 and L3 are turned off.

After the saved session loads, the Customize Input/Output tab shows the configuration updates.

  • A property is added to the Link Properties section of the Properties tab to specify the desired availability percentage (Availability). The value is set to 99.9%.

  • Results are added on the Results tab to compute the total atmospheric attenuation (Total atm att) and total propagation losses (Total prop losses) per the P.618 propagation model. To compute the total atmospheric attenuation, the app runs the computeTotalAttenuation.m function using properties configured in the app. In the formula for the Total atm att property on the Results tab you can see the input parameters as identified by property tag names (PLC1, PG1, PG2, PG3, PL1, N2, PT5, and PL5).

  • The formula for the received isotropic power (Tag: N6) on the Results tab is changed to use NC2 instead of N5.

This figure shows updates to the configuration in the Properties and Results tabs.

Analyze Link Availability

Before analyzing the P.618 scenario, you must download the digital maps file. If you have not downloaded and unpacked the digital maps file, this dialog box will appear. Follow the instructions in the dialog.

After you have downloaded and uncompressed the digital maps file, click Analyze to compute the link budget for the configured P.618 scenario.

The app runs the P.618 scenario to analyze the 99.9% annual availability and then updates the link budget and plotted results. The 99.9% annual availability is satisfied with approximately 4.8 dB of margin for the configured satellite communications link.

Parameters

This figure shows the BUDGET ANALYZER tab with the factory default configuration.

Default satellite link budget app session window, showing the budget analyzer tab

Use the Ground Station, Link, and Satellite tabs to adjust property settings for the link budget entities shown in the Link Canvas tab.

Select the Ground Station tab to set the location, transmitter, and receiver settings for the ground station highlighted in the Link Canvas tab. For information about customizing satellite, ground station, transmitter, receiver, and link properties, and the link budget result computations, see CUSTOMIZE INPUT/OUTPUT.

Select the Satellite tab to set the location, transmitter, and receiver settings for the satellite highlighted in the Link Canvas tab. For information about customizing satellite, ground station, transmitter, receiver, and link properties, and the link budget result computations, see CUSTOMIZE INPUT/OUTPUT.

Select the Link tab to set link characteristics for the link highlighted in the Link Canvas tab. For information about customizing satellite, ground station, transmitter, receiver, and link properties, and the link budget result computations, see CUSTOMIZE INPUT/OUTPUT.

To view or customize input properties and computations used for output, on the BUDGET ANALYZER tab, click Customize Input/Output to switch to the CUSTOMIZE INPUT/OUTPUT tab. In the CUSTOMIZE INPUT/OUTPUT tab, you can

  • Change settings of the satellite, ground station, transmitter, receiver, and link properties from the factory default inputs

  • Add and delete satellite, ground station, transmitter, receiver, and link input properties

  • Add, delete, and modify formulas used to compute link budget output results

This figure show the CUSTOMIZE INPUT/OUTPUT tab with the factory default configuration.

Default satellite link budget app session window, showing the customize input/output tab

In the CUSTOMIZE INPUT/OUTPUT tab, you can

  • Use the Properties tab to change settings of the satellite, ground station, transmitter, receiver, and link properties from the factory default inputs. You can also add and delete satellite, ground station, transmitter, receiver, and link input properties. On the Properties tab you can use the Restore to factory button to load the factory default property configuration in the current app session.

  • Use the Results tab to add, delete, and modify formulas used to compute link budget output results. On the Results tab you can use the Restore to factory button to load the factory default results configuration in the current app session.

Programmatic Use

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satelliteLinkBudgetAnalyzer opens the Satellite Link Budget Analyzer app.

Introduced in R2021a