CTE Wireless & RF Engineering Flashcards
6 cards from real CTE practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 CTE Wireless & RF Engineering flashcards as text
What is the Friis transmission equation used to calculate in RF engineering?
Answer: Received power in a line-of-sight link given transmit power and antenna gains
The Friis transmission equation calculates received power as a function of transmit power, antenna gains, wavelength, and free-space path distance.
Which modulation scheme provides the highest spectral efficiency in a wireless link?
Answer: 256-QAM
256-QAM encodes 8 bits per symbol, giving the highest spectral efficiency among the listed schemes, though it requires a high SNR.
What does VSWR measure in an antenna system?
Answer: Impedance mismatch between transmission line and antenna
Voltage Standing Wave Ratio (VSWR) quantifies impedance mismatch; a VSWR of 1:1 indicates perfect match with no reflected power.
In cellular network planning, what is the primary purpose of frequency reuse?
Answer: To increase network capacity by using the same frequencies in non-adjacent cells
Frequency reuse assigns the same frequency channels to geographically separated cells, multiplying overall network capacity.
Which multiple access technology does LTE use on the downlink?
Answer: OFDMA
LTE downlink uses Orthogonal Frequency Division Multiple Access (OFDMA), which divides bandwidth into sub-carriers assigned to different users.
What is the typical frequency range for the C-band used in fixed satellite services in the United States?
Answer: 3.7 GHz – 4.2 GHz (downlink) / 5.925 GHz – 6.425 GHz (uplink)
Fixed satellite service C-band uses 3.7–4.2 GHz for downlink and 5.925–6.425 GHz for uplink in the United States per FCC allocations.