What type of encoding is used in an...

What type of encoding is used in an...

Question 1 of 27070eRyRjZozrXnTf6AAETzl

What type of encoding is used in an aircraft’s mode C transponder transmission to a ground station of the Air Traffic Control RADAR Beacon System (ATCRBS)?

Question 1 of 27070

Q

What type of encoding is used in an aircraft’s mode C transponder transmission to a ground station of the Air Traffic Control RADAR Beacon System (ATCRBS)?

🔍 Key Concepts

• Mode C transponder purpose and what information it sends to ATC • Basic idea of pulse position modulation (PPM) vs. amplitude or phase modulation • How older ATCRBS (beacon system) replies are structured (discrete pulses in time slots)

💭 Think About

• Think about whether a Mode C reply is a continuous radio signal being varied, or a series of short pulses in specific time locations. • Which of the answer choices best matches a scheme where information is carried by when a pulse occurs rather than its strength or phase? • Ask yourself: are Mode A/C replies digital pulses or an analog-modulated carrier?

✅ Before You Answer

• Confirm that ATCRBS Mode A/C replies are made up of discrete pulses at specific time positions. • Check which modulation type uses timing/position of pulses to encode data, not their amplitude or phase. • Eliminate any answer that clearly refers to analog carrier modulation instead of digital pulse timing.