Section 1 - Basic Characteristics Flashcards
What layers are common to both user and control plane transmissions
PHY, MAC, RLC and PDCP
(T or F) SDAP is a layer used in control plane
False: User plane
(T or F) RRC is a layer used in control plane
True
What are the functions of the 5G MAC layer
Priority handling between logical channels in a UE and between UEs, padding, error correction, multiplexing/demux of MAC SDUs from different logical channels, beam management, RA procedures, mapping between logical and transport channels
What are the functions of the RLC layer
Transfer upper layer PDUs, error correction, reordering 5G RLC data PDUs, duplicate detection, protocol error detection, segmentation, RLC re-establishment
What are the functions of the PDCP layer
Transfer user data, in-sequence delivery of upper layer PDUs, duplicate detection, retransmission, ciphering, timer-based SDU discard
What are the functions of the RRC layer
Broadcasting system information to NAS; establishment, maintenance and release of RRC; security; establishment, configuration, maintenance and release of point-point radio bearers; mobility functions; UE measurement reporting
List the three main segments to which 5G NR targets
eMBB, Massive IoT, uRLLC
Mention six key air enablers of NR
Scalable OFDM, flexible slot-based framework, mmWave, massive MIMO, beam sweeping, advance channel coding (LDPDC)
Which numerologies can be used in the transmission of SSB
15, 30 and 120 kHz
Which is the only numerology that supports extended cyclic prefix
60 kHz
What is the maximum bandwidth supported in FR1
100 MHz
What is the maximum amount of PRBs supported for any numerology
273, for 30kHz SCS
What is the maximum bandwidth supported for 15kHz SCS
50 MHz
How many symbols can form a mini-slot
2, 4 or 7
What are the three types of symbols in the TDD configuration
DL, UL and flexible
Explain the dynamic slot format configuration
RRC configures UEs with multiple slotFormatCombinations, each combination being a list of slot formats for a number of consecutive slots. The UE is configured with SFI-RNTI to monitor PDCCH for SFI (slot format indication). PDDCH dynamically indicates the SFIs for a number of upcoming slots.
Can the dynamic slot format override DL and UL symbols configured by RRC
No
What are self-contained slots
A single slot that contains DL control information, DL data and ACK, mainly used for LLC
What are the main characteristics associated with a BWP
Numerology, bandwidth and frequency location
Is BWP configuration the same for all UEs?
No, the BWP is UE-specific
What’s the main difference between NSA and SA
In NSA, the control plane goes through E-UTRAN
