Downlink Project Description

Posted on Feb 6, 2014

The Skeyeball project is an ongoing project in the Indiana University System Design Methods Laboratory for both graduate and undergraduate students to perform embedded system design and implement various projects. The downlink portion of the project involves transfering data from the plane to the ground by using a single signal. My downlink p

Downlink Project Description
Click here to download the full size of the above Circuit.

roject involves re-implementing Prashant Patel`s project from thesummer of 2000, then compacting and debugging it to achieve the desired operation. The first step is to implement the xilinx code using two Logic Engine Boards to host the plane and ground implementation seperately so that adequate testing with the RF transmitter and receiver can be accomplished. I also re-implemented the analog injection and extraction ciruits with new designs to increase bandwidth. A NTSC signal is generated by the video source and it`s horizontal and vertical synchronizing pulses allow data to be injected at spaces in the signal where the video signal is retracing to the top of the screen and is always black. The data can be injected in these spots and then extracted from the same spot by the same manner. Once the data is extracted, the video signal is set back to black so that there are no side effects in the video image displayed on the monitor. There are 10 of these spaces in each field and a maximum bandwidth of 300 bits per space. The present goal is an established 56kbps downlink, which is around 90 bits per space. The limitation to higher bps is the bandwidth the RF transmitter, receiver and the analog circuitry allows. Maximum bps is determined experimentally. The data is viewed using hyperterminal, so a lower rate is better. Once further parts of the system are operating we can increase the download capabilities. The physical part...

Leave Comment

characters left:

Related Circuits

  • New Circuits



    Popular Circuits

    Circuit transmits ARINC 429 data
    PC home light control system
    Linear light-meter circuit
    Lithium Ion Lithium Poly Charger by LM317
    inverter 12v dc to 120 230v dc with ic
    street light lamp circuit
    Electromechanical relay logic
    Crosswalk Pedestrian Signal and Homemade Controller
    LC filter and LC type filter circuit
    OP27 multiple S-type thermocouple circuit