Mode S Downlink Frames

GetModeSDownlinkFrames streams raw Mode S downlink frames received by one or more sensors.

Request Filters

df_filter

Mode S downlink formats. For example, use 17 for ADS-B extended squitter. Leave empty to include all downlink formats.

sensor_filter

Sensors from which receptions should be included. Leave empty to use all sensors associated with the token.

aircraft_filter

ICAO 24-bit transponder addresses. Leave empty to include all aircraft.

Response Contents

Each response includes:

• target: participant address and address type decoded from the frame

• reply: raw Mode S reply bytes, either 7 or 14 bytes

• receptions: metadata for the sensors that received the signal

• dropped_frames: absolute counter for skipped frames

Reception Metadata

Reception metadata includes server timestamp, sensor timestamp, GNSS timestamp, signal level, noise level, carrier frequency offset, timing base, and timing synchronization source.

Typical Uses

Use downlink frame streaming for raw ADS-B collection, signal-quality analysis, and applications that need per-reception metadata instead of decoded target state.