CTA Wireless Communications & Mobile Technologies

Question 1

Which generation of mobile technology first introduced packet-switched data services alongside circuit-switched voice in the US?

Accepted Answer

2G (GPRS/EDGE)

Answer

1G

Answer

3G (UMTS/HSPA)

Answer

4G LTE

Question 2

What does the term 'handoff' (or handover) refer to in cellular networks?

Accepted Answer

Transferring an active call from one base station to another

Answer

Converting analog signals to digital

Answer

Assigning a frequency channel to a new subscriber

Answer

Switching from voice to data mode

Question 3

In the US, which spectrum band is commonly referred to as 'low-band' 5G and offers the widest coverage?

Accepted Answer

Sub-1 GHz bands (600–900 MHz)

Answer

millimeter wave (mmWave) above 24 GHz

Answer

Mid-band around 3.5 GHz

Answer

C-band at 3.7–3.98 GHz

Question 4

What is the primary purpose of MIMO (Multiple-Input Multiple-Output) technology in wireless systems?

Accepted Answer

To increase spectral efficiency and throughput using multiple antennas

Answer

To reduce transmit power

Answer

To eliminate the need for modulation

Answer

To convert Wi-Fi signals to cellular

Question 5

Which wireless standard defines Wi-Fi 6 (802.11ax)?

Accepted Answer

IEEE 802.11ax

Answer

IEEE 802.11n

Answer

IEEE 802.11ac

Answer

IEEE 802.11ad

Question 6

What is the difference between FDD and TDD in mobile networks?

Accepted Answer

FDD uses separate frequency bands for uplink and downlink; TDD uses the same frequency but alternates time slots

Answer

FDD uses time slots; TDD uses separate frequencies

Answer

FDD is only for 4G; TDD is only for 5G

Answer

FDD requires more antennas than TDD