    Advantages of Patriot's Impulse Radar System

    The key to Patriot's Radar system is its ability to transmit
    and receive pulses barely longer then single cycles at the
    transmit frequency. The first waveform shown here is a pulse
    generated by an earlier Patriot Design, based on "off the
    shelf" antenna technology. The waveform on the bottom was
    produced and received by Patriot's current Design.

    The current Patriot antenna system produces a pulse at the
    desired frequency with little leading or trailing noise. The
    Patriot antenna system provides many advantages over
    pulse-based systems.

    Patriot originally developed the impulse radar system to allow
    time domain processing in Patriot's GPR systems.  Because the
    impulse is extremely short (3 nanoseconds), the time to return
    can be used to gauge the distance traveled by the pulse.

    Furthermore, the transmit and receive antenna's are very
    directional, eliminating much of the multipath components of
    the return signal.

    The short pulse combined with the directional transmit and
    receive to provide us with a number of important advantages:

    - Very low average power during transmission
    - Low interference from other transmitters
    - Transmission invisible to conventional receivers
    - High bandwidth digital data transmission possible
    - Difficult detection by other impulse receivers

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