SBS-2M
Advanced Functionality
The SBS-2M comprises of the professional SBS-2 chassis system in a network configuration, with the option of remote external antenna modules connected to the host by radio, microwave or fibre optic links. The SBS-2M can be configured for Terminal Area or Wide Area Multilateration Surveillance.
Each receiver processes Mode A/C and Mode-S SSR replies (on 1090 MHz), and Mode-S squitter transmissions, including extended squitter messages (ADS-B). Each receiver module decodes and timestamps the transponder reply signals and squitter messages it receives, before transmitting the data to the SBS-2M Target Processor (TP). The advanced target processing software then compares the reports from the various receiver modules to derive target positions based on Time Difference of Arrival (TDOA) of the signal at the different antennas.
Additional decoded data available from Mode S / ADS-B transmissions includes:
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Precise UTC date and time signal was received (using GPS synchronisation) | |
Date/Time of last position update |
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Signal strength | |
Navigational Uncertainty Category (NUC) |
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24-bit aircraft address | |
Aircraft ID |
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Mode-S download format (DF) | |
Aircraft Category |
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Position report derived from aircraft's on board navigation system | |
Mode 3/A 4096 code (Squawk) |
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Altitude reported (Flight level) | |
Squitter status |
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Altitude AMSL (calculated using pressure sensor) | |
Transponder capability |
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Horizontal and Vertical velocity | |
Single antenna flag (SAF) |
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Selected Altitude/Heading | |
Surveillance status (SPI, alert) |
Mode A/C signals provide timestamp and signal strength plus Mode A 4096 code or Mode C altitude data, together with the multilaterated position information.