UPSC Prelims 2026 Question:

Which of the following statements with regard to drone swarms is/are correct? 

1. They use Terahertz band of frequency to communicate with the command centre.
2. Individual drones in the swarm can communicate with other drones in the swarm.
3. GPS Spoofing is a commonly used technique to counter drone swarm attack. 

Select the answer using the code given below :

Answer: 2 

Explanation:  

Drone swarms consist of multiple unmanned aerial vehicles operating in coordination through communication  links, sensors and algorithms. Their strength lies in distributed operation, where drones can share information and  adjust their behaviour collectively. Counter-drone measures often target navigation, communication and control  links of such systems. 

• Drone swarms do not generally use the Terahertz band to communicate with the command centre. Operational drone communications commonly use radio-frequency links such as L-band, S-band, C-band  or other microwave frequencies, while Terahertz communication remains largely experimental and is not  a standard feature of drone swarms. So, statement 1 is not correct. 
• Individual drones in a swarm can communicate with other drones in the swarm. This inter-drone communication allows coordination, formation control, target allocation, obstacle avoidance and  autonomous decision-making. So, statement 2 is correct. 

• GPS spoofing is a commonly discussed counter-drone technique. It involves transmitting false  navigation signals to mislead drones about their actual position, thereby disrupting their route, formation  or target approach. So, statement 3 is correct. 

Therefore, option (2) is the correct answer.