LTE Advanced Flashcards
IMT stands for
International Mobile telecommunication
International Telecommunication Union using Radio (ITU-R) defined 4G mobile technology as ________
1) IMT-2000
2) IMT-Advanced
3) IMT-2020
IMT-Advanced
(IMT-2000 is for 3G andIMT-2020 is for 5G)
IMT advanced requirement
data rate ______ for low mobility and _______ for high mobility
1) 100Mbps, 10Mbps
2) 100Mbps, 100Mbps
3) 1Gbps, 100Mbps
4) 1Gbps, 1Gbps
1 Gbps for low mobility and
100Mbps for high mobility
IMT advanced requirement
support for high mobility up to ____km/hr
1) 100 km/hr
1) 250 km/hr
1) 350 km/hr
1) 500 km/hr
350 km/hr
IMT advanced requirement
spectral efficiency ______ for downlink and ________ for uplink
1) 5bps/Hz, 1.5bps/Hz
1) 10bps/Hz, 3.2bps/Hz
1) 15bps/Hz, 6.7bps/Hz
1) 20bps/Hz, 9.8bps/Hz
15bps/Hz for downlink and
6.7bps/Hz for uplink
IMT advanced requirement
Low latency U-plane < __ms and C-plane < __ms
1) 100, 200
2) 10, 100
3) 100, 10
4) 200, 100
U-plane < 10ms and
C-plane < 100ms
IMT advanced requirement
___ VoIP users per sector/MHz
1) 20
2) 40
3) 60
4) 80
40 VoIP users per sector/MHz
IMT advanced requirement handover interruption ____ for intra-frequency and ____ for inter-frequency
1) 15.5ms, 30ms
1) 27.5ms, 40ms
1) 40ms, 60ms
1) 55ms, 65ms
<27.5ms for intra-frequency and
<40ms for inter-frequency
LTE multiple-access technologies are
1) downlink: SC-FDMA, uplink: SC-FDMA
2) downlink: SC-FDMA, uplink: SC-OFDMA
3) downlink: OFDMA, uplink: SC-FDMA
4) downlink: OFDMA, uplink: OFDMA
downlink: OFDMA,
uplink: SC-FDMA
choose correct
1) 1G/2G has circuit core only
2) 2.5G/3G has circuit and packet core
3) 4G has packet core only
4) all the above
All the above
LTE-Advanced in release 10 allows
1) frequency-selective scheduling in uplink
2) allowed carriers along contiguous block of spectrum
frequency-selective scheduling in uplink.
Release 10 introduces clustered SC-FDMA in uplink.
LTE in release 8 allows
1) frequency-selective scheduling in uplink
2) allowed carriers along contiguous block of spectrum
allowed carriers along contiguous block of spectrum
LTE-Advanced allows
1) downlink: 4X4 MIMO, uplink: 4X4 MIMO
2) downlink: 4X4 MIMO, uplink: 8x8 MIMO
3) downlink: 8x8 MIMO, uplink: 8x8 MIMO
4) downlink: 8x8 MIMO, uplink: 4X4 MIMO
downlink: 8x8 MIMO, uplink: 4X4 MIMO
_______ are used for extending the coverage of main eNB in low coverage environment
1) relay nodes
2) umbrella cells
The relay nodes or low power eNBs
The relay nodes are connected to Donor eNB (DeNB) through ___ interface
1) Un
2) Uu
3) Ur
Un interface
LTE-Advanced in release 10 introduces
1) relay nodes
2) eICIC
3) clustered SC-FDMA in uplink
4) carrier aggregation (CA)
5) Support for Heterogeneous Networks
6) all the above
all the above
_____introduced in 3GPP release 10 to deal with interference issues in
Heterogeneous Networks (HetNet)
1) relay nodes
2) eICIC
3) clustered SC-FDMA in uplink
4) carrier aggregation (CA)
eICIC
eICIC mitigates interference on
1) traffic channels
2) control channels
3) both
both
eICIC uses ______ to mitigate intra-frequency interference in heterogeneous networks
1) power
2) frequency
3) time domain
4) all the above
all the above
An eNB sends a “______” message to the neighbore NB about interference level per physical resource block.
1) interference imformation
2) load information
3) congestion imformation
4) resource information
“load information”.
message to the neighbore NB about
interference level per physical resource block. The neighbor adjusts DL power levels at those blocks
Only control channels and cell-specific pilots, no user data. Allows UEs in CRE region to mitigate macro-cell interference
1) ABS
2) CA
3) SDCCH
Almost Blank Subframes (ABS)
a cost effective way for operators to utilize their fragmented spectrum spread across different or same bands in order to improve end
user throughput
1) relay nodes
2) eICIC
3) clustered SC-FDMA in uplink
4) carrier aggregation (CA)
carrier aggregation (CA)
Each individual RF carrier in carrier aggregation is known as a
1) sub carrier
1) component carrier
1) traffic carrier
1) multiplexed carrier
Component Carrier
The release 10 version of the 3GPP specifications defines signalling to support up to
1) 4 Component Carriers (Bandwidth:80MHz)
2) 5 Component Carriers (Bandwidth:100MHz)
3) 10 Component Carriers (Bandwidth:200MHz)
4) 3 Component Carriers (Bandwidth:60MHz)
5 Component Carriers (Bandwidth:100MHz)
The release 10 version of the 3GPP specifications defines individual
Component Carriers to be
1) backwards compatible
2) forward compatible
backwards compatible, so they can be used by release 8 and release 9 devices
Component Carriers
1) need to be adjacent
2) can be located in different operating bands
can be located in different operating bands.
need not to be adjacent.
The combination of large macro cells with small cells results in _____networks.
1) homogeneous networks
2) heterogeneous networks
heterogeneous networks
CoMP transmission stands for
Coordinated multi-point transmission
CoMP is used in
1) uplink (reception)
2) downlink (transmission)
3) both
both
Joint transmission from multiple cells (like soft handover)
1) carrier aggregation (CA)
2) eICIC
3) CoMP
4) none
CoMP transmission
(Coordinated multi-point)
Central eNodeB combines received
signals (like soft handover)
1) carrier aggregation (CA)
2) eICIC
3) CoMP
4) none
CoMP reception
(Coordinated multi-point)
DPS (Dynamic Point Selection)
1) carrier aggregation (CA)
2) eICIC
3) CoMP transmission
4) CoMP reception
CoMP transmission
(Coordinated multi-point)
SSPS (semi-static point selection)
1) carrier aggregation (CA)
2) eICIC
3) CoMP transmission
4) CoMP reception
CoMP reception
(Coordinated multi-point)
Transmission to a UE from one point only; suchpoint is changed semi-statically
1) SSPS
2) eICIC
3) CA
SSPS (semi-static point selection)
eICIC stands for
enhanced inter-cell interference coordination
eICIC introduced in 3GPP release 10 to deal with interference issues in 1)
1) Homogeneous networks
2) Heterogeneous Networks
Heterogeneous Networks (HetNet)
Release ___ will mark the start of 5G work in 3GPP
1) Release 13
2) Release 14
3) Release 15
Release 14
SON stands for
Self Organizing Network
SON involves
1) Self configuration
2) Seld optimization
3) Self-healing
4) all the above
all the above
LTE advanced considers SON feature
1) Self configuration
2) Seld optimization
3) Self-healing
Self-healing
With CoMP transmission, the transmitter can share data load even if they are not collocated
T
CoMP: Coordinated Multi-Point
_______ introduced in 3GPP release 11 to increase control channel capacity
1) carrier aggregation (CA)
2) eICIC
3) CoMP
4) ePDCCH
ePDCCH (enhanced PDCCH)
ePDCCH uses PDSCH resources for transmitting control information unlike
release 8 PDCCH which can only use control region of subframes
In LTE release 11, support for ____is added
1) uplink positioning
2) downlink positioning
uplink positioning
____ wireless systems can be viewed as a logical extension to the smart antennas
1) MIMO
2) CoMP
3) Carrier aggregation
MIMO
Previously these multiple paths only served to introduce interference. By using _______, these additional paths can be used to advantage
1) MIMO
2) CoMP
3) Carrier aggregation
MIMO
MIMO wireless technology is able to
considerably increase the capacity of a given channel while still obeying Shannon’s law.
T
Where there are more than one antenna at either end of the radio link, this is termed
1) MIMO
2) CoMP
3) Carrier aggregation
MIMO
MIMO provides improvements in
1) channel robustness
2) channel throughput
3) both
both channel robustness as well as channel throughput.
In any case for MIMO spatial multiplexing the number of receive antennas must be ____ the number of transmit antennas.
1) equal to or greater than
2) equal to or less than
3) both
equal to or greater than
_______ codes are used for MIMO systems to enable the transmission of multiple copies of a data stream across a number of antennas
1) carrier-time block codes
2) carrier-space block codes
3) space-time block codes
4) frequency-time block codes
Space-time block codes (STBC)
A space time block code is usually represented by a matrix. Each row represents a ______ and each column represents _________
1) one antenna’s transmissions over time, time slot
2) time slot, one antenna’s transmissions over time
time slot, one antenna’s transmissions over time
The _______ scheme is an ingenious transmit diversity scheme for two transmit antennas that does not require transmit channel knowledge
1) MIMO Alamouti
2) Adaptive array systems
3) Phased array systems
MIMO Alamouti
Alamouti scheme performs beamforming in time by adjusting the weights in ______ domain
1) time
2) space
time domain instead of the usual spatial domain.
Beamforming van be used with _______
1) MIMO only
2) any antenna system
2) any antenna system
Smart antennas can be divided into two groups
1) Phased array systems
2) __________
Adaptive array systems (AAS)
Smart antennas can be divided into two groups
1) _________
2) Adaptive array systems (AAS)
Phased array systems
This smart antenna has a number of pre-defined patterns
1) Phased array systems
2) Adaptive array systems (AAS)
Phased array systems
This smart antenna has an infinite number of patterns
1) Phased array systems
2) Adaptive array systems (AAS)
Adaptive array systems (AAS)
______ move the beam in real time
1) Phased array systems
2) Adaptive array systems (AAS)
Adaptive array systems (AAS)
MU-MIMO stands for
Multi-user MIMO
_______ is often considered as an extension of Space Division Multiple Access, SDMA
1) SU-MIMO
2) CP-OFDM
3) MU-MIMO
4) SC-FDMA
MU-MIMO
________ provides capacity gain
1) SU-MIMO
2) MU-MIMO
MU-MIMO
_____ provides increased data rate for the single user
1) SU-MIMO
2) MU-MIMO
SU-MIMO
Multiplexing gain referes to
1) SU-MIMO
2) MU-MIMO
MU-MIMO
Interference reduction referes to
1) SU-MIMO
2) MU-MIMO
SU-MIMO
MU-MIMO provides a higher throughput when the signal to noise ratio is_______ as compared to SU-MIMO
1) low
2) high
high
SU-MIMO provides a higher throughput when the signal to noise ratio is_______ as compared to MU-MIMO
1) low
2) high
low
Perfect CSI (Channel State Information) is required for
1) SU-MIMO
2) MU-MIMO
MU-MIMO
No CSI (Channel State Information) is needed for
1) SU-MIMO
2) MU-MIMO
SU-MIMO
MIMO-MAC stands for
Multiple Access Channel (uplink)
MIMO-BC stands for
Broadcast Channel (downlink)
MU-MIMO uplink is
1) Multiple Access Channel (MAC)
2) Broadcast Channel (BC)
Multiple Access Channel
MU-MIMO downlink is
1) Multiple Access Channel (MAC)
2) Broadcast Channel (BC)
Broadcast Channel
MU-MIMO pre-interference cancellation techniques known as _________
1) Dirty Paper Coding
2) space time block coding
3) Beamforming
Dirty Paper Coding (DPC)
The technique consists of precoding the data in order to cancel the interference.
some propagation issues like channel rank loss and antenna correlation affects less in
1) SU-MIMO
2) MU-MIMO
MU-MIMO
CSI (Channel State Information) requires the use of the available bandwidth which is a disadvantage for
1) SU-MIMO
2) MU-MIMO
MU-MIMO
_____ is used to mitigate macro-cell interference
1) ABS
2) CA
3) SDCCH
Almost Blank Subframes (ABS)
