L18 Pre-flight

L18 Pre-flight#

Block 2: RF Electronic Warfare — Lesson 18: Active Deception Work this before L18. Pre-flights are never collected — in class, anyone may be cold-called to present any question at the board, and that recitation is the participation grade.

Assumed pre-class reading#

  • L17 wrap-up

  • The Jupyter Book Reading page for L18 — deception vs noise, DRFM, false-target injection, range-gate pull-off, and decoys.

Quiz questions (5 items, ~5 minutes)#

Q1. (Multiple choice) How does deceptive jamming differ from noise jamming?

  • [ ] (a) Deception uses more power

  • [ ] (b) Noise raises the noise floor to mask returns; deception injects false but believable returns so the radar tracks the wrong thing

  • [ ] (c) Deception only works at long range

  • [ ] (d) There is no real difference

Q2. (Multiple choice) What makes a DRFM repeater more dangerous than a simple transponder?

  • [ ] (a) It transmits at higher power

  • [ ] (b) It digitizes, stores, and replays a phase-coherent copy, so it can set precise delay/Doppler and is hard to tell from a real return

  • [ ] (c) It never needs to know the radar’s frequency

  • [ ] (d) It works without receiving the radar pulse

Q3. (Multiple choice) Range-gate pull-off (RGPO) defeats a tracking radar by:

  • [ ] (a) Burning out the receiver

  • [ ] (b) Capturing the range gate with a cover pulse, then growing the false return’s delay to drag the gate off the true target before blinking off

  • [ ] (c) Lowering the radar’s transmit power

  • [ ] (d) Jamming every frequency at once

Q4. (Multiple choice) A towed or expendable decoy protects an aircraft mainly by:

  • [ ] (a) Absorbing the missile’s warhead

  • [ ] (b) Presenting a stronger, believable target that transfers the radar’s (or missile’s) lock away from the aircraft

  • [ ] (c) Jamming the GPS signal

  • [ ] (d) Reducing the aircraft’s RCS

Q5. (Short answer) Name a counter to range-gate pull-off and explain why it works. Then give one general reason deception is “not free.”

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