Pulse Radar Signal Processing

A pulse radar system transmits short, repetitive RF pulses and measures the time delay of the returned echoes to detect and locate targets.

The range to a target is determined from the round-trip time of the pulse, while Doppler processing can be used to estimate target velocity.

To obtain the radar heat maps and/or IQ Data using the pulse radar, follow these steps:
  1. In the results tree, select Power (MS) or Power.
  2. Click Display > Radar > Pulse Radar.
  3. Click on the radar result pixel.
  4. On the Pulse Radar Postprocessing dialog, specify the required radar parameters:
    • Waveforms
      Defines the modulation of the transmitted pulse. The selected waveform affects range resolution and pulse compression performance:
      • Rectangular Pulse: Unmodulated simple pulse but offers limited range resolution.
      • Frequency-Modulated Pulse: Linearly frequency-modulated (chirp) pulse, which improves range resolution​.
      • Phase-Modulated Pulse: Pulse modulated with Barker codes, which offers good autocorrelation properties. All 13 Barker codes are supported.
    • Pulse Repetition Frequency
      The number of pulses transmitted per second, specified in the dialog in kHz. It determines the maximum unambiguous range and velocity.
    • Pulse Duration (Pulse Width)
      The duration of each transmitted pulse, specified in the dialog in µs. It has an impact on the range resolution, where shorter pulses provide finer range resolution. For pulse-compressed waveforms, range resolution is determined by the signal bandwidth rather than the pulse width alone.
    • Number of Pulses
      The number of pulses within a single coherent processing interval (CPI). It has an impact on the velocity resolution, where more pulses provide better velocity (Doppler) resolution.
    • Sampling Rate
      The rate at which the received signal is sampled, specified in the dialog in MHz.

Output

You can specify the desired output, following the same output options described as for FMCW radar output. For angle of arrival (AoA) estimation, the same requirements described previously still apply.

On the receiver side, a matched filter is used to correlate the incoming signal with a reference signal (a replica of the transmitted pulse), enhancing the signal-to-noise ratio (SNR), detection sensitivity, and range accuracy.

The IQ output for pulse radar generates two files: Raw IQ Data, captured before the matched filter and representing the unprocessed complex signal; and Compressed IQ Data, captured after matched filtering and representing the pulse-compressed signal.
Figure 1. Snapshot from a time-variant simulation showing a pulse radar heat map indicating the range and radial velocity of the aircraft.