Which of the following is NOT a subdivision of electronic countermeasures?

• A. Jamming
• B. Neutralisation
• C. Deception
• D. Frequency Hopping

Answer: (D)

Electronic countermeasures are actions that degrade, deny, or deceive an opponent’s use of the electromagnetic spectrum. Jamming directly interferes with enemy receivers to reduce their effectiveness. Deception feeds false signals or misleading information to sensors to cause incorrect responses. Neutralisation aims to disable enemy electronics so they can’t operate. Frequency hopping, however, is a spread-spectrum technique that rapidly changes the carrier frequency to avoid interference and detection, keeping our own communications and radar resilient in contested environments. It’s a defensive, anti-jamming approach used to counter interference rather than an attack on enemy equipment, so it isn’t categorized as a subdivision of electronic countermeasures.