Radar Target Generation Software offers two personalities—Pulse Aware and Pulse Invariant.

  • Pulse Aware—A personality that detects and processes incoming radar pulses separately, allowing for blanking between targets. It provides the same processing functions of the Pulse Invariant personality, but with support for only three simultaneous targets. Use the Pulse Aware personality for most use cases.
  • Pulse Invariant—The original personality has been renamed Pulse Invariant. Use the Pulse Invariant personality when there is a need for four simultaneous targets, when testing a continuous waveform (CW) radar, or require predictive mode support.
    • Note Radar Target Generation Software version 1.3 or later supports Pulse Aware.

    Both Pulse Aware and Pulse Invariant personalities apply configurations in a synchronized manner. The options for controlling when the configuration change occurs are as follows:

    • Software Trigger
    • External Trigger
    • Pulse Rising Edge
    • Pulse Falling Edge
    • Time Offset from First Trigger
    • Time Offset from Last Trigger

    While the personalities share these synchronization methods, how they are applied differ.

    Table 1. Comparing Pulse Aware and Pulse Invariant
    Feature Pulse Aware Pulse Invariant
    Simultaneous target support 3 4
    Range window No restrictions 4 targets must fit within a limited range window
    • 52.4 µs (approximately 8 km) for PXIe-5830/5831/5832/5841
    • 26.2 µs (approximately 4 km) for PXIe-5842
    Glitch-free operation Yes Can change configuration during a pulse, which results in a glitch
    High pulse repetition frequency (PRF) >500 kHz support Yes No
    Continuous waveform (CW) target support No Yes
    Predictive Mode support No Yes

    Pulse Aware

    Pulse Aware works in complex environments—especially when radar pulse repetition frequency (PRF) is high and there are possibly thousands of radar pulses in flight at one time. This personality actively detects pulses and keeps track of the following individual properties:

    • Arrival time
    • Pulse width
    • Frequency

    Pulse Aware is similar to Pulse Invariant as to when configuration changes are synchronized. However, it differs in that changes are not applied immediately, but instead are applied when the current acquired radar pulse will be regenerated as a target. This could mean that there are thousands of active configurations in the system—each applied when it is time to generate the corresponding target.

    Pulse Aware also supports digital and analog blanking—only signals from detected pulses are generated as targets, and other quiet times are blanked.

    Pulse Invariant

    Pulse Invariant works optimally when there is a single pulse in flight at a time, meaning a radar generates a pulse and waits for its return before generating another pulse. This personality works by using the active configuration to continually generate data from all the acquired data. It applies the same math to data between pulses as it does to the radar pulses themselves. This personality supports continuous waveform (CW) radars, unlike Pulse Aware.

    Configuration changes occur globally—a change in configuration causes an immediate change in the target processing functions.