Which type of modulator is described as line-pulsed in typical radar configurations?

Which type of modulator is described as line-pulsed in typical radar configurations?

• A. Spark-gap
• B. Traveling-wave
• C. Line-pulsed
• D. Ring-modulated

Answer: (C)

A line-pulsed modulator uses a transmission-line pulse-forming network to store energy and release it as a short, high-voltage pulse. In typical radar configurations, this line-based approach provides clean, repeatable pulse widths and fast rise/fall times, which are essential for accurate range measurement and stable operation at the required repetition rates. The energy is held in a capacitor bank and dumped into the line through a fast switch, producing a near-rectangular pulse that travels along the line to the transmitter. This is distinct from spark-gap modulators, which rely on a gas discharge to start conduction and can have less precise timing and stability. Traveling-wave modulators involve control of a wave along a structure and are a different implementation concept, not described as line-pulsed in the same way. Ring-modulated devices are used for other RF modulation tasks rather than generating the main high-power radar pulse.

A line-pulsed modulator uses a transmission-line pulse-forming network to store energy and release it as a short, high-voltage pulse. In typical radar configurations, this line-based approach provides clean, repeatable pulse widths and fast rise/fall times, which are essential for accurate range measurement and stable operation at the required repetition rates. The energy is held in a capacitor bank and dumped into the line through a fast switch, producing a near-rectangular pulse that travels along the line to the transmitter.

This is distinct from spark-gap modulators, which rely on a gas discharge to start conduction and can have less precise timing and stability. Traveling-wave modulators involve control of a wave along a structure and are a different implementation concept, not described as line-pulsed in the same way. Ring-modulated devices are used for other RF modulation tasks rather than generating the main high-power radar pulse.