LTTS-Batch 2_Week1 LTTS-Batch 2_Week1 The number of attempts remaining is 1 1 / 30 1. Why is TDD particularly attractive for NR's mmWave (FR2) deployments? a. TDD allows flexible, asymmetric allocation of downlink/uplink capacity using a single, often large, unpaired spectrum block b. TDD eliminates the need for guard periods c. TDD requires no synchronization between cells d. TDD works only with FDD-paired spectrum 2 / 30 2. How many subcarriers make up one resource block (RB) in NR? a. 10 b. 14 c. 20 d. 12 3 / 30 3. What does the SSB (SS/PBCH Block) consist of? a. PSS, DMRS, and CSI-RS b. PDSCH, PDCCH, and PBCH c. SRS, PBCH, and PDCCH d. PSS, SSS, and PBCH 4 / 30 4. What is the primary purpose of frequency reuse in cellular network design? a. To increase the transmit power of each cell b. To eliminate the need for handovers between cells c. To allow the same frequencies to be reused in non-adjacent cells and serve more users with limited spectrum d. To reduce the number of cell sites needed 5 / 30 5. Which layers does the gNB DU (Distributed Unit) terminate? a. RLC, MAC, and PHY b. RRC and PDCP c. PDCP and SDAP d. NAS and RRC 6 / 30 6. What does SA (Standalone) 5G deployment use for both RAN and core? a. eNB and 5GC b. gNB and 5GC, with no LTE dependency c. gNB and EPC d. eNB and EPC only 7 / 30 7. How long is one LTE/NR radio frame? a. 1 ms b. 5 ms c. 20 ms d. 10 ms 8 / 30 8. Which of the following best describes cell splitting? a. Switching a cell from FDD to TDD b. Dividing a single frequency into multiple channels c. Merging two cells into one to save power d. Subdividing a larger cell into smaller cells to increase capacity in high-demand areas 9 / 30 9. What is the primary purpose of DMRS (Demodulation Reference Signal)? a. To help the receiver estimate the channel for coherent demodulation of the associated data channel b. To broadcast the physical cell ID c. To carry MIB/SIB information d. To measure downlink interference only 10 / 30 10. In FDD (Frequency Division Duplex), how are uplink and downlink separated? a. Same frequency, different time slots b. Uplink is disabled entirely c. Different, paired frequency bands used at the same time d. Same frequency and same time, separated by coding 11 / 30 11. How many OFDM symbols does an SSB occupy? a. 7 b. 1 c. 4 d. 14 12 / 30 12. What is the main interface between a UE and the RAN called, in both LTE and NR? a. N2 interface b. Uu interface c. S1 interface d. X2 interface 13 / 30 13. Why does a link experiencing Rayleigh fading typically need a higher SNR than an AWGN-only link to achieve the same BER? a. Rayleigh fading only affects the transmitter, not the receiver b. Fading adds additional error events beyond thermal noise alone, requiring extra margin to reach the same BER c. Rayleigh fading eliminates thermal noise entirely d. AWGN channels always have lower bandwidth 14 / 30 14. Which interface connects two gNBs to each other (inter-gNB) in NR? a. NG b. Xn c. S1 d. F1 15 / 30 15. Which frequency range does FR1 cover in 5G NR? a. Above 100 GHz b. Below approximately 7.125 GHz (sub-6 GHz) c. 24.25-52.6 GHz d. Only the 700 MHz band 16 / 30 16. Which fading model applies when a dominant line-of-sight path exists alongside scattered reflections? a. Rician fading b. Rayleigh fading c. Doppler fading d. AWGN-only channel 17 / 30 17. What does SINR (Signal-to-Interference-plus-Noise Ratio) capture that RSRP alone does not? a. The UE's battery level b. The impact of both interference and noise relative to the desired signal, not just raw signal strength c. Only the transmit power of the serving cell d. The number of active bearers 18 / 30 18. What architectural style does the 5G Core (5GC) use that the LTE EPC does not? a. A purely circuit-switched core b. Service-Based Architecture (SBA), where network functions expose and consume services via APIs c. An architecture with no defined network functions d. A single monolithic hardware appliance 19 / 30 19. What is a modulated waveform's constellation diagram primarily used to visualize? a. The physical antenna layout b. The frequency spectrum only c. The core network topology d. The amplitude and phase state of each transmitted symbol 20 / 30 20. Which interface connects the 5G gNB to the 5G Core? a. F1 b. S1 c. NG d. X2 21 / 30 21. In TDD (Time Division Duplex), how are uplink and downlink separated? a. Different frequency bands b. Distinct encryption keys c. The same frequency, using different time slots d. Separate physical antennas only 22 / 30 22. Which interface connects the gNB-CU to the gNB-DU? a. Xn b. NG c. F1 d. X2 23 / 30 23. In NR numerology, how is subcarrier spacing (SCS) calculated for numerology μ? a. 15 / 2^μ kHz b. μ × 100 kHz c. 15 × 2^μ kHz d. 15 + μ kHz 24 / 30 24. What is a Bandwidth Part (BWP) in NR? a. A contiguous subset of the total carrier bandwidth that a UE operates within at a given time b. A dedicated uplink-only carrier c. The full system bandwidth broadcast in the SIB d. A separate physical antenna panel 25 / 30 25. In LTE's E-UTRAN architecture (3GPP TS 36.300), what is the radio base station called? a. gNodeB (gNB) b. NodeB c. Base Transceiver Station (BTS) d. eNodeB (eNB) 26 / 30 26. What is the primary purpose of the cyclic prefix (CP) in an OFDM symbol? a. To combat inter-symbol interference caused by multipath delay spread b. To reduce the number of subcarriers c. To encrypt the payload d. To increase transmission power 27 / 30 27. What causes multipath fading in a wireless channel? a. Multiple reflected/scattered copies of the same signal arriving at different times and combining constructively or destructively b. Using too many subcarriers c. A single, unobstructed line-of-sight path d. Excessive transmit power 28 / 30 28. In the gNB CU/DU functional split, which layers does the CU (Centralized Unit) terminate? a. PHY and RLC b. MAC and PHY c. RRC and PDCP d. RLC and MAC 29 / 30 29. What does RSRP (Reference Signal Received Power) measure? a. The power level of a specific downlink reference signal, used to assess signal strength b. The ratio of signal power to total received power including interference c. The number of resource blocks allocated d. The uplink transmit power of the UE 30 / 30 30. Which core network architecture does LTE use? a. EPC (Evolved Packet Core) b. 5GC (5G Core) c. NGC (Next Generation Core) d. IMS only Your score is
