Statement 1 is not correct: Drones in a swarm conventionally use radio frequency (RF) communication devices to communicate with each other and with command centres. Terahertz (THz) band is a futuristic research area being explored for next-generation communications.
Statement 2 is correct: A key feature of drone swarms is that individual drones communicate with each other within the swarm, as well as with the drone control station, through wireless communication channels.
Statement 3 is correct: GPS spoofing is implemented as an effective electronic countermeasure technique to mislead drone navigation systems, dynamic spoofing combined with no-fly zone enforcement proved particularly effective in forcing drones to land or exhibit erratic behaviour.
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The Notification for the Civil Services Examination, 2021 was released by the Commission on March 04, 2021. The notification contains all the details related to the examination dates, number of vacancies, eligibility criteria, syllabus, application process, fee, exam centers etc. The exam is being conducted to fill in 712 vacancies as listed in the notification with 22 vacancies reserved for Persons with Benchmark Disability. The Preliminary examination will be held on October 10 2021. Candidates can visit the Commission’s website  to fill the application form. Detailed instructions for filling up online applications have been provided on the website. The application window was closed on March 24 2021. The admit cards for the Preliminary Examination were made available from September 16 2021. The admit cards can be downloaded from the Commission’s website on the above mentioned link.