RL 20 Trial overview
For internal use
1
© Nokia Siemens Networks
LTE Radio Parameters / v001 / Document Number
General
Project Phase
RL10 + 1800MHz, 15 MHz, MOCN, S1 flex
CP (M01/2011)
QPT (B12/2010)
Pilot projects
Early Projects
Release Trial(s)
For internal use
2
© Nokia Siemens Networks
LTE Radio Parameters / v001 / Document Number
P8
C5.1
RL20 Demo + Barcelona
Sales Trial(s)
Testing Schedule (Pilot, EP and Trials)
CP
JAN
FEB
MARCH
C5
APRIL
MAY
JUNE
P8
JULY
Pilot Projects
Telia DK / Fi
Telia Sonera SW / DK/ Fi
DTAG (800MHz)
DTAG (1.8/2.6 GHz)
RFP 1st August

Early Projects
LG U+
LG U+
SKT

Elisa Fi
TEF O2 (800 MHz)

Lightsquared
RL20 Trials (BL lead, BL supported, Region alone)

Optus
Verizon
TMO US
US Cellular / AMX Mexico
CUC
CUC
VDF Italy
TMO Croatia
MTS Belarus
Smartone HK
Megafone
Indosat
For internal use
3
© Nokia Siemens Networks
LTE Radio Parameters / v001 / Document Number
M1

Physical channels and signals - recap
For internal use
4
© Nokia Siemens Networks
LTE Radio Parameters / v001 / Document Number
Overview - Channels
Upper Layers
DL
UL
RLC
DCCH
DTCH
CCCH
MTCH
MCCH
DTCH
DCCH
CCCH
PCCH
BCCH
Logical channels
MAC
UL-SCH
RACH
MCH
DL-SCH
PCH
BCH
Transport channels
PHY
PUSCH
PUCCH
PRACH
LTE Radio Parameters / v001 / Document Number
PMCH
For internal use
5
© Nokia Siemens Networks
PDCCH
PCFICH
PHICH
PDSCH
PBCH
Air interface
Downlink Physical Signals and Channels
• Downlink Physical Signals
– Reference Signals
– Synchronisation Signals
• Downlink Physical Channels
– Physical Broadcast Channel (PBCH)
– Physical Downlink Shared Channel (PDSCH)
– Physical Downlink Control Channel (PDCCH)
– Physical Control Format Indicator Channel (PCFICH)
– Physical Hybrid-ARQ Indicator Channel (PHICH)
– Physical Multicast Channel (PMCH)
For internal use
6
© Nokia Siemens Networks
LTE Radio Parameters / v001 / Document Number
Overview – Control Information
CQI, PMI, RI,
ACK/NACK
CQI, PMI, RI,
ACK/NACK
SR
eNode B
DL control
configuration
1x per cell
RNTI
DL scheduling
UL Grant
UL PWRC
n x per cell
HARQ Info
For internal use
7
© Nokia Siemens Networks
LTE Radio Parameters / v001 / Document Number
Resource Block
• Physical Resource Block or Resource Block (PRB or RB):
12 subcarriers in frequency domain (180kHz) x 1 slot period in time domain
(0.5ms)
Capacity allocation is based on Resource
Subcarrier 1 0 1 2 3 4 5 6 0 1 2 3 4 5 6
Blocks
0 1 2 3 4 5 6 0 1 2 3 4 5 6
0 1 2 3 4 5 6 0 1 2 3 4 5 6
180 KHz
0 1 2 3 4 5 6 0 1 2 3 4 5 6
0 1 2 3 4 5 6 0 1 2 3 4 5 6
0 1 2 3 4 5 6 0 1 2 3 4 5 6
0 1 2 3 4 5 6 0 1 2 3 4 5 6
0 1 2 3 4 5 6 0 1 2 3 4 5 6
0 1 2 3 4 5 6 0 1 2 3 4 5 6
0 1 2 3 4 5 6 0 1 2 3 4 5 6
0 1 2 3 4 5 6 0 1 2 3 4 5 6
• Note: Although 3GPP definition of RB
refers to 0.5ms, in some cases it is
possible to found that RB refers to 12
subcarriers in frequency domain and 1ms
in time domain. In particular, since the
scheduler in the eNodeB works on TTI
basis (1ms) RBs are considered to last
1ms in time domain. They can also be
known as ‘scheduling resource blocks’
Subcarrier 12 0 1 2 3 4 5 6 0 1 2 3 4 5 6
1 slot
1 slot
1 ms subframe
For internal use
8
© Nokia Siemens Networks
LTE Radio Parameters / v001 / Document Number
Resource
Element
Physical Layer Downlink Summary
DL-Channel
DLOverview
Frequency
Central 72 subcarriers (6 RBs)
Total System Bandwidth e.g. 10MHz (50 RBs)
DL-Physical Data & Control Channel
For internal use
9
© Nokia Siemens Networks
LTE Radio Parameters / v001 / Document Number
Reference Signals: OFDMA Channel Estimation
• Channel estimation in LTE is based on reference signals (like CPICH functionality
in WCDMA)
• Reference signals position in time domain is fixed (0 and 4 for Type 1 Frame)
whereas in frequency domain it depends on the Cell ID
• In case more than one antenna is used (e.g. MIMO) the Resource elements
allocated to reference signals on one antenna are DTX on the other antennas
• Reference signals are modulated to identify the cell to which they belong.
symbols
6
0
symbols
6
subcarriers
subcarriers
0
Antenna 1
For internal use
10
© Nokia Siemens Networks
LTE Radio Parameters / v001 / Document Number
Antenna 2
Synchronization Signals allocation (DL)
• Synchronization signals:
– Transmitted during the 1st and 11th slots
within a radio frame
– Occupy the central 62 Subcarriers (around
the DC subcarrier) to facilitate the cell
search
– 5 Subcarriers above and 5 Subcarriers
below the synch. Signals are reserved and
transmitted as DTx
– Synchronisation Signal can indicate 504
(168 x 3) CellID different values and from
those one can determine the location of
cell specific reference symbols
For internal use
11
© Nokia Siemens Networks
LTE Radio Parameters / v001 / Document Number
Generic - Physical Layer Cell Id
• Physical Layer Cell Identity defines a cell, but it is not necessarily unique in the network
• It consists of the two parts; Physical layer Cell Identity Group and Physical layer Identity
• Physical Layer Cell Identity = 3 x Physical layer Cell Identity Group + Physical layer Identity
• Decoded during synchronisation using primary and secondary sync signal
• PSS/SSS are used for:
– Initial cell search and neighbor cell search
• As a result of cell search the UE should acquire:
– PHY cell ID
Strongest Signal
– DL center frequency
– 10ms and 5ms timing
– CP length
– Duplex mode (TDD/FDD)
Cell ID Group 0
(3 L1 id’s)
168 Cell ID
groups
Cell ID Group i
(3 L1 id’s)
Primary
Synchronization Signal
L1 id, slot (0/10)
Secondary
Synchronisation Signal
Group 167
Phy L Cell ID
Physical Layer
Cell ID, Frame
Alignment
For internal use
12
© Nokia Siemens Networks
LTE Radio Parameters / v001 / Document Number
DL Physical Channels Allocation
• PBCH:
– Occupies the central 72 subcarriers across 4
symbols
– Transmitted during second slot of each 10 ms
frame on all antennas
• PCFICH:
– Transmitted during the first symbol of each TTI
– Occupies up to 16 RE per TTI
• PHICH:
– Tx during 1st symbol of each TTI or alternativ during
symbols 1 to 3 of each TTI  PhichDur
– Each PHCIH group occupies 12 RE
• PDCCH:
– Occupies the REs not used by PCFICH and PHICH
and Reference Signals within the first 1, 2 or 3
symbols of each TTI (case 1.4 MHz: within the first 2,
3 or 4 symbols)
– In RL09/10: configuration static by
MaxNbrOfOFDMSymsForPDCCH
• PDSCH:
– Is allocated the RE not used by signals or other
physical channels
For internal use
13
© Nokia Siemens Networks
LTE Radio Parameters / v001 / Document Number
RB
UL Physical Channels
• PUSCH: Physical Uplink Shared Channel
– Intended for user data (carries traffic for multiple
UEs) and control data
– If control data is to be sent when traffic data is being
transmitted, UE multiplexes both streams together
• PUCCH: Physical Uplink Control Channel
– Carries H-ARQ Ack/Nack indications, uplink
CCCH
DCCH
DTCH
Logical
RLC
Transport
RACH
scheduling request, CQIs and MIMO feedback
– Only control information is sent. The UE uses
Resources Element at the edges of the channel
UL-SCH
MAC
PHYS.
• PRACH: Physical Random Access Channel
– For Random Access attempts. PDCCH indicates the
resource elements for PRACH use
– PBCH contains a list of allowed preambles (64 per
cell) and the required length of the preamble.
For internal use
14
© Nokia Siemens Networks
LTE Radio Parameters / v001 / Document Number
PRACH
PUSCH
PUCCH
UL Channels
The mapping of transport channels and UL control information (UCI) to physical
channels is a task of the physical layer (PHY). Furthermore reference signals are
provided by the physical layer which do not transfer any higher layer information.
Logical channel mapping is provided by the MAC layer.
Physical channel for data and signalling from higher layers:
• Physical Uplink Shared Channel, PUSCH.
• Physical Random Access Channel, PRACH.
Physical channels with UL control - related signalling:
• Physical Uplink Control Channel, PUCCH.
and signals with no information of higher layers:
• Demodulation Reference Signals (DRS).
• Sounding Reference Signal (SRS).
For internal use
15
© Nokia Siemens Networks
LTE Radio Parameters / v001 / Document Number
UE Channel state information (CSI) feedback types in LTE
• The purpose of CSI feedback is to provide
•
•
•
•
•
the eNodeB information about DL channel
state to help in the scheduling decision.
Compared to the WCDMA/HSPA, the main
new feature in the channel feedback is the
frequency selectivity of the report
CSI is measured by the UE and signaled to
the eNodeB using PUCCH or PUSCH
Channel state information in LTE can be
divided into three categories:
– CQI - Channel Quality Indicator
(2) UE CSI
measurement
– RI - Rank Indicator
– PMI - Precoding Matrix Indicator
In general the CSI reported by the UE is just a
recommendation
– The eNodeB does not need to follow it
The corresponding procedure for providing
information about the UL channel state is
called Channel Sounding and it is done using
the Sounding Reference Symbols, SRS (not
considered in this presentation)
For internal use
16
© Nokia Siemens Networks
LTE Radio Parameters / v001 / Document Number
(1) eNodeB
transmission
(3) UE
feedback
PDCCH Uplink Grant
• The eNodeB allocates the Uplink resources to the UEs by sending an UL
Grant
UL Grant contents
•Resource Block assignment
–Indicates the PRB the UE may use for transmission
–Signaling format: index of starting PRB & number of contiguous PRBs
•Modulation and Coding Scheme and the Redundancy version (5 bits)
•Power control command (2 bits)
•Cyclic Shift for the demodulation reference symbols
•CQI request flag
•PUSCH Hopping flag
•New data indicator
TDD specific
•UL index (indicates which UL subframe the grant refers to)
•Downlink assignment index
For internal use
17
© Nokia Siemens Networks
LTE Radio Parameters / v001 / Document Number