Long Term Evolution (LTE) Technology Overview Long Term Evolution (LTE) will ensure the competitiveness of UMTS for the next ten years and beyond by providing a high-data rate, low-latency and packet-optimized system. Also known as E-UTRA (Evolved Universal Terrestrial Radio
Multiple access schemes and physical layer signal generation OFDMA in downlink
Access), LTE is part of 3GPP Release 8 specifications. The innovations that LTE brings to the UMTS world include:
QAM modulator
Data source
❙ New multiple access schemes for both LTE FDD and TD-LTE
Mapping to subcarriers
LTE downlink
Addition of cyclic prefix
N-point IFFT
Physical channels Physical downlink shared channel (PDSCH)
carries user data
Physical multicast channel (PMCH)
carries MBMS user data
Not used for transmission at this antenna point
Physical downlink control channel (PDCCH)
Reference symbol PCFICH PDCCH PHICH
carries control information (DCI = downlink control information)
Physical control format indicator channel (PCFICH)
indicates format of PDCCH (CFI = control format indicator)
Physical hybrid ARQ indicator channel (PHICH)
carries ACK/NACKs (HI = HARQ indicator) for uplink data packets
Physical broadcast channel (PBCH)
provides information during cell search, e.g. on system bandwidth
❙ Scalable bandwidth up to 20 MHz ❙ MIMO antenna technology
Subcarriers
Example structure, 1 antenna signal (of a 2×2 MIMO setup) shown
s l o b
❙ New data and control channels
m y s A M D F O
❙ New network and protocol architecture ❙ Specific test and measurement challenges
1 resource block = 180 kHz = 12 subcarriers with spacing of 15 kHz
Commercial LTE networks have been launched worldwide, starting with the first network in Sweden in Decem-
Frequency
ber 2009. 3GPP Release 9 features added further enhance-
U E2
U E3 Physical signals
1 subframe = 2 slots = 1 ms = 1 transmission time interval
IMT-Advanced, developed as LTE Release 10 and beyond, has
UE4
1 radio frame = 10 subframes = 10 ms
been accepted as a 4G technology. Known as LTE-Advanced, it complies with or exceeds the ITU established criteria in all
U E1
1 slot = 7 OFDMA symbols 1) = 0.5 ms
ments to LTE. The 3GPP candidate technology submission for
UE5
U E6
Time
1)
For F or normal cyclicprefix duration.
Primary and secondary synchronization signals
provide acquisition of cell timing and identity during cell search
Reference signal
enables channel estimation
aspects. Rohde &Schwarz is the right partner for making your
SC-FDMA in uplink
LTE products happen. Our test solutions were the first on the market and since then have evolved to a full
QAM modulator
Data source
product portfolio from a single-source supplier, covering applications from R & D to conformance.
Subcarriers
1) 2)
Band6 is notapplicable. Europeonly (ETSI EN301 908-2).
FDD (in MHz): 1) UL: 1920 to 2) UL: 1850 to 3) UL: 1710 to 4) UL: 1710 to to 5) UL: 824 to 6) UL: 830 7) UL: 2500 to to 8) UL: 880 9) UL: 1749.9 to 10) UL: 1710 to 11) UL: 1427.9 to 12) UL: 699 to 13) UL: 777 to 14) UL: 788 to 15) UL: 1900 to 16) UL: 2010 to 17) UL: 704 to 18) UL: 815 to 19) UL: 830 to 20) UL: 832 to 21) UL: 1447.9 to 22) UL: 3410 to 23) UL: 2000 to 24) UL: 1626.5 to 25) UL: 1850 to 26) UL: 814 to 27) UL: 807 to 28) UL: 703 to – 29) UL: 30) UL: 2305 to 31) UL: 452.5 to – 32) UL: TDD (in MHz): 33) 1900 to 34) 2010 to 35) 1850 to 36) 1930 to 37) 1910 to 38) 2570 to 39) 1880 to 40) 2300 to 41) 2496 to 42) 3400 to 43) 3600 to 44) 703 to
1980 1910 1785 1755 849 840 2570 915 1784.9 1770 1447.9 716 787 798 1920 2025 716 830 845 862 1462.9 3490 2020 1660.5 1915 849 824 748 2315 457.5
DL: DL: DL: DL: DL: DL: DL: DL: DL: DL: DL: DL: DL: DL: DL: DL: DL: DL: DL: DL: DL: DL: DL: DL: DL: DL: DL: DL: DL: DL: DL: DL:
2110 1930 1805 2110 869 875 2620 925 1844.9 2110 1475.9 729 746 758 2600 2585 734 860 875 791 1495.9 3510 2180 1525 1930 859 852 758 717 2350 462.5 1452
to to to to to to to to to to to to to to to to to to to to to to to to to to to to to to to to
UE1
UE3
1 radio frame = 10 subframes = 10 ms
1)
3 MH z
5 MH z
1 0 MH z
1 5 MH z
20 MH z
6
15
25
50
75
10 0
Modula Mod ulation schemes
DL: QPSK, 16QAM, 64QA 64QAM M UL: QPSK, 16QAM, 64QAM (optional for UE)
carries user data
Physical uplink control channel (PUCCH)
carries control information (UCI = uplink control information)
Physical random access channel (PRACH)
preamble transmission for initial access
UE4
Demodulation reference signal
enables channel estimation
Sounding reference signal
enables channel quality evaluation
Time
For normal cyclic prefixduration.
MIMO antenna technology
1 . 4 MH z
Physical uplink shared channel (PUSCH)
Physical signals
U E2
1 subframe = 2 slots = 1 ms = 1 transmission time interval
Resource blocks (RB) (1 RB = 180 kHz)
DL :O FDM A UL: SC-FDMA
Demodulation reference signal for PUCCH
Frequency
Channel bandwi dth
DL:150Mbit/s / s (UE U E categor goryy 4,2x2MIM MIMO, O, 20 MHz), MHz), 300 Mbit/s (UE category 5, 4x4 MIMO, 20 MHz) UL: 75 Mbit/s (UE category 5,20 MHz)
Physical channels
PUCCH (used by UEs not scheduled in this s ubframe)
1 slot = 7 SC-FDMA symbols1) = 0.5 ms
LTE enhancements
LTE MIMO characteristics
3GPP LTE Release 9
Number of eNB transmit antennas 1, 2 or 4
Feature
Number of UE receive antennas
2 or 4
Multimedia broadcast multicast services (MBMS)
support for efficient point-to-multipoint transmission
D L t r an sm sm itit di ve ve rs rs it y
s pa pa ce ce fr eq eq ue ue nc nc y b lo lo ck ck co di di ng ng (S (S FB FB C) C)
LT E po si si titi on on in g
DL spatial mult ultipl iplexi e xing ng
codebo ebookok-based pre precod coding ing,, maximum of 2 parallel code words
s up up po po rt rt f or n et et wo wo rk rk -a -a ss ss is te te d gl gl ob ob al al n av ig at at io n sa te te llll it e sy st st em em ( GN SS SS ),), o bs er er ve ve d ti me me d if fe fe re re nc nc e of a rr rr iv iv al ( OT DO DO A) A) , and enhanced cell ID positioning
LT E d ua ua l l ay ay er er b ea mf mf or or mi mi ng ng
M IM IM O sp at at ia l m ul ul titi pl pl ex ex in g su pp pp or or t in ca ca se se of of b ea mf mf or or mi mi ng ng
DL cyclic delay diversity
antenna-specific cyclic shifts
Multicarrier/multi-RAT base stations
RF requirements for base stations supporting multiple carriers and/or multiple radio access technologies (RAT)
Public warning system (PWS)
broadcast reception mechanism and associated paging to accommodate reception of alert messages (extension of the earthquake and tsunami warning system (ETWS) in LTE Release 8)
Home eNB/femtocell
RF requirements tailored to different base station classes (wide area, local area and specifically home base stations)
Self-organizing networks (SON)
addition t ional support for mobility t y robustness optimizati z ation, o n, mobility t y load balancing optimiza m ization and RACH optimiza m ization use cases
U L M IM O mo de
Peak Pe ak datarate
LTE uplink
Demodulation reference signal for PUSCH
1 resource block = 180 kHz = 12 subcarriers with spacing of 15 kHz
1920 2025 1910 1990 1930 2620 1920 2400 2690 3600 3800 803
M ul ti pl eac ces s
PUSCH for UE1
A M D F C S
2170 1990 1880 2155 894 885 1) 2690 960 1879.9 2170 1495.9 746 756 768 2620 2) 2600 2) 746 875 890 821 1510.9 3590 2200 1559 1995 894 869 803 728 2360 467.5 1496
Addition of cyclic prefix
N-point IFFT
Example structure, no frequency hopping
s l o b m y s
Key parameters Frequencyrange (E-UTRA bands)
Mapping to subcarriers
M-point DFT
m ul ti- us er /c ol lab or at ive MI MO , transmit antenna selection
Objective
Rohde & Schwarz LTE test solutions so lutions RF development and production testing
Mobile network testing
Protocol stack testing and IOT
Signal generators, and fading simulator
Benchmarking, optimization, drive tests
Appli cati on layer testing with IP analysis from ipoque
R&S®SGT100A
Network and protocol architecture R&S®SMW200A eNB
MME
Inter-cell RRM
NAS security
Radiobearer control
Idlestate mobility handling
Connectionmobility control Radioadmission control eNBmeasurement configuration& pr provision ovision
S-GW
R&S®SMBV100A
R&S®CMW500protocol tester
P-GW
Mobility anchoring
UE IPaddress allocation
Signal and spectrum analyzers
Diversity Benchmarker II
Packet filtering
EPS bearer control
Diversity Ranger
Internet
MME/S-GW
RF conformance and network operator acceptance testing
MME/S-GW
Dynamicresource allocation(scheduler) RRC
R&S®FSW
R&S®FSV
PDCP RLC MAC
S1
S1 S1
PHY
S1
R&S®FPS E-UTRAN
X2 eNB
X2
X2
eNB
Oscilloscopes
QualiPoc Android
Power meters R&S®TSME with R&S®ROMES
eNB
Glossary: 3GPP = 3rd Generation Partnership Project, 4G = 4th Generation Mobile Communications Technology, ARQ = Automatic Repeat Request, DFT = Discrete Fourier Transformation, DL = Downlink, eNB = evolved NodeB, EPS = Evolved Packet System, E-UTRA = Evolved Universal Terrestrial Radio Access, FDD = Frequency Division Duplex, HARQ = Hybrid ARQ, IFFT = Inverse Fast Fourier Transform, IMT = International Mobile Telecommunications, IOT = Interoperability Testing, IP IP = Internet Protocol, ITU = International Telecommunication Union, MAC = Medium Access Control, MBMS = Multimedia Broadcast Multicast Service, MIMO = Multiple Input Multiple Output, MME = Mobility Management Entity, NAS = Non Access Stratum, OFDMA = Orthogonal Frequency Division Multiple Access, P-GW = Packet Data Network Gateway, PBCH = Physical Broadcast Channel, PCFICH = Physical Control Format Indicator Channel, PDCCH = Physical Downlink Control Channel, PDCP = Packet Data Convergence Protocol, PDSCH = Physical Downlink Shared Channel, PHICH = Physical HARQ Indicator Channel, PHY = Physical Layer, PMCH = Physical Multicast Channel, PRACH = Physical RACH, PUCCH = Physical Uplink Control Channel, PUSCH = Physical Uplink Shared Channel, QAM = Quadrature Amplitude Modulation, QPSK = Quadrature Phase Shift Keying, RACH = Random Access Channel, RAT = Radio Access Technology, RF = Radio Frequency, RLC = Radio Link Control, RRC = Radio Resource Control, RRM = Radio Resource Management, S-GW = Serving Gateway, SC-FDMA = Single Carrier Frequency Division Multiple Access, TD-LTE = Time Division – Long Term Evolution, TDD = Time Division Duplex, UE = User Equipment, UL = Uplink, UMTS = Universal Mobile Telecommunications System.
Installation and maintenance R&S®RTO/RTE/RTM
R&S®NRP
Wideband radio communication tester
R&S®CMW500
www.rohde-schwarz.com/technology/LTE
R&S®FSH/ZVH Handheld spectrum/cable and antenna analyzer
R&S®TS-LBSlocation based services test system
R&S®TS8980 RF and RRM test system
