Link Analysis¶

Link Analysis computes pairwise access intervals between one primary asset and one or more secondary assets. It can also compute RF link budget metrics when transmitter, receiver, and antenna chains are configured.

Engineering Questions¶

When can the primary asset see each secondary asset?
Which constraints limit the contact?
What is the range, elevation, and off-boresight geometry during access?
Does the RF link budget meet the required Eb/N0 margin?

Inputs¶

Input	Description
Primary asset	Source endpoint for the analysis.
Secondary assets	One or more target endpoints.
Time step	Coarse access sampling step.
Geometry step	Sampling step for saved geometry during intervals.
Link budget enabled	Whether RF metrics are computed after access.
Link direction	Direction used to build RF chains.
RF chain mode	Automatic or configured chain selection.
Required Eb/N0	Margin threshold for link budget.
Extra path loss	Additional link loss in dB.

Access Engine Pipeline¶

flowchart TD
    A["Resolve primary and secondary assets"] --> B["Build access endpoints"]
    B --> C["Precompute positions and normals"]
    C --> D["Evaluate LoS, FoV, and constraints"]
    D --> E["Extract intervals"]
    E --> F["Refine boundaries"]
    F --> G["Optional geometry sampling"]
    G --> H["Store access_by_pair and geometry_by_pair"]

Link Budget Pipeline¶

flowchart TD
    I["Access intervals"] --> C["Resolve RF chain"]
    C --> TX["Transmitter and TX antenna"]
    C --> RX["Receiver and RX antenna"]
    TX --> G["Directional gains"]
    RX --> G
    G --> B["Budget per interval"]
    B --> M["Received power, C/N0, Eb/N0, margin"]

Main Configuration Parameters¶

Field	Meaning
`primary_asset_guid`	Primary asset GUID.
`secondary_asset_guids`	Target asset GUIDs.
`use_assets_interval`	Uses natural asset validity interval when available.
`time_step_s`	Coarse access step.
`geometry_dt_s`	Geometry sampling step inside access intervals.
`line_color`, `line_width`	Link visualization styling.
`enable_link_budget`	Enables RF budget computation.
`required_ebn0_db`	Required Eb/N0 threshold.
`extra_path_loss_db`	User-defined extra path loss.
`include_polarization_loss`	Applies TX/RX polarization mismatch loss.
`noise_bandwidth_mode`	Receiver or manual noise bandwidth selection.

Outputs¶

Output	Description
`access_by_pair`	Contact intervals for each primary-secondary pair.
`geometry_by_pair`	Optional geometry arrays for each pair.
`access_meta`	Timeline, pair count, and engine configuration.
`link_budget_by_pair`	Budget chains and interval metrics.
`link_budget_meta`	RF computation metadata.

Interpretation¶

Contact and link budget are related but separate. A contact interval means geometry and constraints permit access. A successful link budget additionally requires valid RF chain configuration and sufficient margin.