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AAUSAT3 - AIS1

under construction

AIS1 is an AIS receiver based on an ADF702x series integrated radio serviced by a AT90CAN128 at 8MHz.

It consists of

  • An ADF702x radio frontend which delivers a bit stream through a SPI interface to...
  • an AT90CAN128 which as the first steps carry out
    • Trainings sequence detection - when applicable
    • HDLC frame detection - <0x7E>NRZi and bit-stuffed AIS frame<0x7E>
    • NRZi decoding and bit de-stuffing
    • and last AIS frame validation (CRC-16)
  • FreeRTOS OS and CSP network

Frames are fully stored as they are received according to selected filters and a flash storage system preserves information.

AIS1 are capable of running even with a damaged flash system(radiation).


AIS and capacity

AIS are transmitting with 9600 baud. Standard messages are 168 bit(not including HLDC frame, training etc) so in praxis less than 5 messages pr second pr channel can be received.


AIS - Automatic Identification System