Concepts of 3GPP LTE.ppt

For internal use only
1 © Nokia Siemens Networks /
Concepts of 3GPP LTE
Long Term Evolution

Orthogonal Frequency Division Multiplexing
25.892 Figure 1: Frequency-Time Representation of an OFDM Signal
OFDM is a digital multi-carrier modulation scheme, which uses a large
number of closely-spaced orthogonal sub-carriers. Each sub-carrier is
modulated with a conventional modulation scheme (such as QPSK,
16QAM, 64QAM) at a low symbol rate similar to conventional single-carrier
modulation schemes in the same bandwidth.

Why OFDM for the downlink?
OFDM already widely used in non-cellular technologies and was considered
by ETSI for UMTS in 1998
CDMA was favoured since OFDM requires large amounts of baseband
processing which was not commercially viable ten years ago
OFDM advantages
• Wide channels are more resistant to fading and OFDM equalizers are
much simpler to implement than CDMA
• Almost completely resistant to multi-path due to very long symbols
• Ideally suited to MIMO due to easy matching of transmit signals to the
uncorrelated RF channels
OFDM disadvantages
• Sensitive to frequency errors and phase noise due to close subcarrier
spacing
• Sensitive to Doppler shift which creates interference between subcarriers
• Pure OFDM creates high PAR which is why SC-FDMA is used on UL
• More complex than CDMA for handling inter-cell interference at cell edge

CDMA vs. OFDM
CDMA
• All transmissions at full system bandwidth
• Symbol period is short – inverse of system bandwidth
• Users separated by orthogonal spreading codes
OFDM
• Transmission variable up to system bandwidth
• Symbol period is long – defined by subcarrier spacing and
independent of system bandwidth
• Users separated by FDMA & TDMA on the subcarriers

OFDM vs. OFDMA
LTE uses OFDMA – a variation of basic OFDM
OFDM = Orthogonal Frequency Division Multiplexing
OFDMA = Orthogonal Frequency Division Multiple Access
OFDMA = OFDM + TDMA
User 1
User 2
User 3
Subcarriers
Symbols
(Time)
OFDM
Subcarriers
Symbols
(Time)
OFDMA
OFDMA’s dynamic allocation enables better use of the channel for multiple
low-rate users and for the avoidance of narrowband fading & interference.

LTE uses SC-FDMA in the uplink
Why SC-FDMA?
SC-FDMA is a new hybrid modulation technique combining the low PAR
single carrier methods of current systems with the frequency allocation
flexibility and long symbol time of OFDM
SC-FDMA is sometimes referred to as Discrete Fourier Transform Spread
OFDM = DFT-SOFDM
TR 25.814 Figure 9.1.1-1 Transmitter structure for SC-FDMA.
DFT
Sub-carrier
Mapping
CP
insertion
Size-NTX Size-NFFT
Coded symbol rate= R
NTX symbols
IFFT
Frequency domain Time domain
Time domain

Comparing OFDM and SC-FDMA
QPSK example using N=4 subcarriers
The following graphs show
how this sequence of QPSK
symbols is represented in
frequency and time
1, 1 -1,-1 -1, 1 1, -1 1, 1 -1,-1 -1, 1 1, -1
15 kHz
Frequency
fc
V
CP
OFDMA
Data symbols occupy 15 kHz for
one OFDMA symbol period
SC-FDMA
Data symbols occupy N*15 kHz for
1/N SC-FDMA symbol periods
60 kHz Frequency
fc
V
CP

OFDM modulation
1,1 +45°
-1,-1 +225°
-1,1 +135°
1,-1 +315°
f0
(F cycles)
f0 + 15 kHz
(F+1 cycles)
f0 + 30 kHz
(F+2 cycles)
f0 + 45 kHz
(F+3 cycles)
One OFDMA symbol period
…
…
…
…
Each of N subcarriers is
encoded with one QPSK
symbol
N subcarriers can
transmit N QPSK
symbols in parallel
One symbol period
The amplitude of the combined four
carrier signal varies widely depending
on the symbol data being transmitted
With many
subcarriers the
waveform
becomes
Gaussian not
sinusoidal
Null created by transmitting
1,1 -1,-1 -1,1 1,-1
1,1
-1,1
1,-1
-1,-1
I
Q

SC-FDMA modulation
To transmit the sequence:
1, 1 -1,-1 -1, 1 1,-1
using SC-FDMA first create a
time domain representation
of the IQ baseband sequence
+1
-1
V(Q)
One SC-FDMA
symbol period
+1
-1
V(I)
One SC-FDMA
symbol period
Perform a DFT of length N
and sample rate N/(symbol
period) to create N FFT bins
spaced by 15 kHz
V,Φ
Frequency
Shift the N subcarriers
to the desired
allocation within the
system bandwidth
V,Φ
Frequency
Perform IFFT to create
time domain signal of the
frequency shifted original
1,1
-1,1
1,-1
-1,-1
Insert cyclic prefix
between SC-FDMA
symbols and transmit
Important Note: PAR
is same as the original
QPSK modulation
1,1
-1,1
1,-1
-1,-1
I
Q

What is MIMO
Multi-Input Multi-Output
Space-Time Processing ( 2D processing )
Tx
M-Antennas
Rx
N-Antennas
CHANNEL

SISO
Single-Input Single-Output
SIMO
Single-Input Multi-Output
MISO
Multi-Input Single-Out

Why MIMO
• Increasing channel capacity
• Increasing robustness
• Increasing coverage
MIMO Classification
• Spatial Multiplexing
• Spatial Diversity

Spatial Multiplexing
(2 Tx BS, 2 Rx MS)
• Matrix B with vertical encoding takes one set of data (“layer”) and maps it
to 2 transmit streams, with half the data on each antenna: doubles the
transmitted data rate (rate 2)
• Transmitted signals pass through 4 channels hxx. Signals at receive
antennas are a combination of signals from both Tx antennas.
• Signal recovery requires knowledge of channels, which are estimated from
pilots
[ ]
[ ]=[ ] s0
s1
r0
r1
h00 h01
h10 h11
R=HS
or
S=H-1R
Bits to
Symbol
Mapping
e.g. QPSK
Tx
Symbol
to
Antenna
Mapping
b0 ,b1 ,b2 ,b3... s0, s1, S2, S3, ...
1,1,1,0... -1-j1, 1-j1...
s0, s2...
s1 ,s3...
I
11
01 00
t1, t2 (time)
10
Q
Antenna 0
Antenna 1
r0, r2 ...
Rx
r1, r3 ...
h00
h01
h10
h11
Antenna 0
Antenna 1

0 0 0 1 1 0 0 1
0 0 0
1 0
1 1 1
1 1 0 0 1 1
r h s h s n h h
r s n
h h
r s n
r h s h s n
 
 
   
  
  
     
     
  
     

        
 

r Hs n
s0, -s1
*
s1 ,s0
*
TX
h0
h1
r0, r1 ...
RX
Solution: 0 0
1 0 1
2 2
1
1 0
0 1
1
1
s r
h h
r
h h
h h
s







 
   
        
  
  
 
 
s H r
t1, t2
Transmission Diversity using Alamouti STBC

Single user MIMO
SU-MIMO
eNB 1 UE 1
Σ Σ
= data stream 1
= data stream 2

Multiple user MIMO
UE 2
UE 1
eNB 1
MU-MIMO
Σ
= data stream 1
= data stream 2

The LTE air interface
Consists of two main components – signals and channels
Physical signals
• These are generated in Layer 1 and are used for system
synchronization, cell identification and radio channel
estimation
Physical channels
• These carry data from higher layers including control,
scheduling and user payload
The following is a simplified high-level description of the
essential signals and channels.
eMBMS, MIMO and some of the alternative frame and CP
configurations are not covered here for reasons of time

Signal definitions
DL Signals Full name Purpose
P-SCH Primary Synchronization Channel Used for cell search and
identification by the UE. Carries part
of the cell ID (one of 3 orthogonal
sequences).
S-SCH Secondary Synchronization
Channel
Used for cell search and
identification by the UE. Carries the
remainder of the cell ID (one of 170
binary sequences).
RS Reference Signal (Pilot) Used for DL channel estimation.
Exact sequence derived from cell ID,
(one of 3 * 170 = 510).
UL Signals Full name Purpose
RS (Demodulation) Reference Signal Used for synchronization to the UE
and UL channel estimation

Channel definitions
DL Channels Full name Purpose
PBCH Physical Broadcast Channel Carries cell-specific information
PDCCH Physical Downlink Control Channel Scheduling, ACK/NACK
PDSCH Physical Downlink Shared Channel Payload
UL Channels Full name Purpose
PRACH Physical Random Access Channel Call setup
PUCCH Physical Uplink Control Channel Scheduling, ACK/NACK
PUSCH Physical Uplink Shared Channel Payload

Signal modulation and mapping
DL Signals Modulation Sequence Physical Mapping Power
Primary
Synchronization Signal
(P-SCH)
One of 3 Zadoff-Chu
sequences
72 subcarriers centred
around DC at OFDMA
symbol #6 of slot #0
[+3.0 dB]
Secondary
Synchronization Signal
(S-SCH)
Two 31-bit M-sequences
(binary) – one of 170 Cell
IDs plus other info
72 subcarriers centred
around DC at OFDMA
symbol #5 of slot #0
Reference Signal (RS)
OS*PRS defined by Cell
ID (P-SCH & S-SCH)
Every 6th subcarrier of
OFDMA symbols #0 & #4
of every slot
[+2.5 dB]
UL Signals Modulation Sequence Physical Mapping Power
Reference Signal (RS) uth root Zadoff-Chu
SC-FDMA symbol #3 of
every slot

Channel modulation and mapping
DL Channels Modulation Scheme Physical Mapping
Physical Broadcast Channel
(PBCH)
QPSK
72 subcarriers centred around
DC at OFDMA symbol #3 & 4 of
slot #0 and symbol #0 & 1 of slot
#1. Excludes RS subcarriers.
Physical Downlink Control
Channel (PDCCH)
QPSK
OFDMA symbol #0, #1 & #2 of
the first slot of the subframe.
Excludes RS subcarriers.
Physical Downlink Shared
Channel (PDSCH)
QPSK, 16QAM,
64QAM
Any assigned RB
UL Channels Modulation Scheme Physical Mapping
Physical Random Access
Channel (PRACH)
QPSK Not yet defined
Physical Uplink Control
Channel (PUCCH)
BPSK & QPSK
Any assigned RB but not
simultaneous with PUSCH
Physical Uplink Shared
Channel (PUSCH)
QPSK, 16QAM,
64QAM
Any assigned RB but not
simultaneous with PUCCH

OFDM (DL) – Physical Layer
Frequency
#0
#1
#2
#3
#4
#5
#19
#18
#17
#16
NBW
DL subcarriers
NBW
RB subcarriers (=12)
Power

Physical Layer definitions – TS36.211
Frame Structure
Ts = 1 / (15000x2048)=32.552nsec
Ts: Time clock unit for definitions
Frame Structure type 1 (FDD/TDD)
FDD: Uplink and downlink are transmitted separately
TDD: Subframe 0 and 5 for downlink, others are either downlink or uplink
#0 #2 #3 #18
#1 ………. #19
One subframe
One slot, Tslot = 15360 x Ts = 0.5 ms
One radio frame, Tf = 307200 x Ts = 10 ms
Subframe 0 Subframe 1 Subframe 9

Agilent Confidential
Page 24
Slot Structure ( Time Domain )
7 OFDM symbols @ Normal CP
Cyclic Prefix
160 2048 144 2048 144 2048 144 2048 144 2048 144 2048 144 2048
1slot = 15360 Ts
13 Aug 2007
0 1 2 3 4 5 6
6 OFDM symbols @ Extended CP
Cyclic Prefix
512 2048
1slot = 15360 Ts
4 5 5
4
512 2048 512 2048 512 2048 512 2048
512 2048
5
3
2
1
0 4
 
2048
15000
1
s 

T
3 OFDM symbols @Extended CP downlink only
Cyclic Prefix
1024 4096
1slot = 15360 Ts
0 1 2
1 2
1024 4096 1024 4096

Slot structure and physical resource element
Downlink – OFDM
NDL
symb OFDM symbols
One downlink slot, Tslot
:
:
NDL
RB x NRB
sc subcarriers
Resource block
NDL
symb x NRB
sc
Resource element
(k, l)
l=0 l=NDL
symb – 1
NRB
sc subcarriers
Condition NRB
sc
NDL
symb
Frame
Structure
type 1
Frame
Structur
e type 2
Normal
cyclic prefix
∆f=15kHz 12 7 9
Extended
cyclic prefix
∆f=15kHz 12 6 8
∆f=7.5kHz 12 3 4
Resource Block
0.5 ms x 180 kHz

Slot structure and physical resource element
Uplink – SC-FDMA
NUL
symb SC-FDMA symbols
One uplink slot, Tslot
:
:
NUL
RB x NRB
sc subcarriers
Resource block
NUL
symb x NRB
sc
Resource element
(k, l)
l=0 l=NUL
symb – 1
NRB
sc subcarriers
Condition NRB
sc
NUL
symb
Frame
Structure
type 1
Frame
Structure
type 2
Normal
cyclic prefix
12 7 9
Extended
cyclic prefix
12 6 8
Resource Block
0.5 ms x 180 kHz

Frame Structure (DL) – Slot/Frame
Nsymb
DL OFDM symbols (=7 OFDM symbols @ Normal CP)
Cyclic Prefix
160 2048 144 2048 144 2048 144 2048 144 2048 144 2048 144 2048 (x Ts)
1slot = 15360
1
0 2 3 4 5 6 1
0 2 3 4 5 6
0 1 2 3 4 5 6
P-SCH
S-SCH
PBCH
PDCCH
Reference Signal
1 frame
1 sub-frame
1 slot
#0 #1 #8
#2 #3 #4 #5 #6 #7 #9 #10 #11 #12 #19
#13 #14 #15 #16 #17 #18
Ts = 1 / (15000x2048)=32.552nsec
Configuration
CP length Guard interval
FS type1 FS type2
Normal CP ∆f=15kHz
160 (#0) 512 (#8 slot#0)
224 otherwise
0 (slot#)
288 otherwise
144 (#1..#6)
Extended CP
∆f=15kHz 512 (#0 .. 5)
768 (#7 slot#0)
512 otherwise
0 (slot#)
288 otherwise
∆f=7.5kHz 1024 (#0..#2)
1280 (#3 slot#0)
1024 otherwise
-----

Ts = 1 / (15000x2048)=32.552nsec
Ts: Time clock unit for definitions
Frame Structure type 2 (TDD)
DwPTS, T(variable)
One radio frame, Tf = 307200 x Ts = 10 ms
One half-frame, 153600 x Ts = 5 ms
#0 #2 #3 #4 #5
One subframe, 30720 x Ts = 1 ms
Guard period, T(variable)
UpPTS, Ｔ(variable)
One slot,
Tslot =15360 x Ts = 0.5 ms
#7 #8 #9
For 5ms switch-point periodicity
For 10ms switch-point periodicity

TDD Downlink and Uplink Allocation
Configuration Switch-
point
periodicity
Subframe number
0 1 2 3 4 5 6 7 8 9
0 5 ms D S U U U D S U U U
1 5 ms D S U U D D S U U D
2 5 ms D S U D D D S U D D
3 10 ms D S U U U D D D D D
4 10 ms D S U U D D D D D D
5 10 ms D S U D D D D D D D
6 10 ms D S U U U D S U U D
•5ms switch-point periodicity: Subframe 0, 5 and DwPTS for downlink,
Subframe 2, 7 and UpPTS for uplink
•10ms switch-point periodicity: Subframe 0, 5,7-9 and DwPTS for downlink,
Subframe 2 and UpPTS for Uplink

#0 #1 #8
#2 #3 #4 #5 #6 #7 #9
1
0 2 3 4 5 6 1
0 2 3 4 5 6 1
0 2 3 4 5 6 1
0 2 3 4 5 6
1
0 2 3 4 5 6
1 0 2 3 4 5 6
Nsymb
Cyclic Prefix
160 2048 144 2048 144 2048 144 2048 144 2048 144 2048 144 2048 (x Ts)
1slot = 15360
0 1 2 3 4 5 6
Ts = 1 / (15000x2048)=32.552nsec
1 slot
Subframe 0
Downlink
P-SCH
S-SCH
PBCH
PDCCH
PDSCH
Reference Signal
Uplink
Reference Signal
(Demodulation)
PUSCH
UpPTS
Downlink TDD Resource Mapping ( Single Antenna Port )
1
0 2 3 4 5 6 1
0 2 3 4 5 6
Subframe 1
(Special Field)
Subframe 2 Subframe 3

Frame Structure Type 1 (DL) - Physical Mapping
P-SCH - Primary Synchronization Channel
S-SCH - Secondary Synchronization Channel
PBCH - Physical Broadcast Channel
PDCCH - Physical Downlink Control Channel
PDSCH – Physical Downlink Shared Channel
Reference Signal – (Pilot)
64QAM
16QAM QPSK
Frequency
Time

Downlink – Let’s verify this with the 89600 VSA
1
0 2 3 4 5 6 1
0 2 3 4 5 6
Slot#0 Symbol#0
RS only
RS + PDCCH

1
0 2 3 4 5 6 1
0 2 3 4 5 6
Slot#0 Symbol#1
PDCCH

1
0 2 3 4 5 6 1
0 2 3 4 5 6
Slot#0 Symbol#3
PBCH
PBCH + PDSCH

1
0 2 3 4 5 6 1
0 2 3 4 5 6
Slot#0 Symbol#4
RS only
RS + PBCH
RS + PBCH + PDSCH

1
0 2 3 4 5 6 1
0 2 3 4 5 6
Slot#0 Symbol#5
S-SCH
S-SCH + PDSCH

P-SCH
P-SCH + PDSCH
1
0 2 3 4 5 6 1
0 2 3 4 5 6
Slot#0 Symbol#6

RS only
RS + PBCH
1
0 2 3 4 5 6 1
0 2 3 4 5 6
Slot#1 Symbol#0
RS + PBCH + PDSCH

Downlink – Let’s verify this with the 89600 VSA (Mixed)
1
0 2 3 4 5 6 1
0 2 3 4 5 6
Slot#0 Symbol#4
RS only
RS + PBCH
RS + PBCH + PDSCH
(QPSK)
RS + PBCH + PDSCH
(QPSK+16QAM)
RS + PBCH + PDSCH
(QPSK+16QAM+64QAM)

Frame Structure (UL) – Slot/Frame
Nsymb
Cyclic Prefix
160 2048 144 2048 144 2048 144 2048 144 2048 144 2048 144 2048 (x Ts)
1slot = 15360
1
0 2 3 4 5 6
0 1 2 3 4 5 6
Reference Signal
(Demodulation)
1 slot
#0 #1 #8
#2 #3 #4 #5 #6 #7 #9 #10 #11 #12 #19
#13 #14 #15 #16 #17 #18
1 frame
1
0 2 3 4 5 6
1 sub-frame
Configuration
CP length
Guard
interval
FS type1 FS type2
Normal CP
160 (#0)
224 (#0..#8) 288
144 (#1..#6)
Extended CP 512 (#0..#5) 512 (#0 ..#7) 256

Frame Structure Type 1 (UL) - Physical Mapping
64QAM
16QAM QPSK
PUSCH - Primary Uplink shared Channel
Reference Signal – (Demodulation)
Frequency
Time

PUSCH
Uplink – Let’s verify this with the 89600 VSA (Sample#1)
1
0 2 3 4 5 6 1
0 2 3 4 5 6
Slot#0 Symbol#0

PUSCH
1
0 2 3 4 5 6 1
0 2 3 4 5 6
Slot#0 Symbol#3

PUSCH
1
0 2 3 4 5 6 1
0 2 3 4 5 6
Slot#0 Symbol#0

PUSCH
1
0 2 3 4 5 6 1
0 2 3 4 5 6
Slot#0 Symbol#3
Uplink – Let’s check it by VSA (Sample#2)

Agenda
LTE Context and Timeline
LTE major features
Overview of the LTE air interface
Agilent LTE design and test solutions
• Test items
• Simulation
• Baseband
• Sources
• Analysis
• Integrated mobile test platform

LTE development challenges
Shortened time-plan for development and deployment
• Development in parallel with standards refinements
Early requirement for full functional testing
• Interoperability testing likely to show up different
interpretations of standards
• Mix of FDD and TDD based testing
• System test for MIMO architecture
Channel bandwidth up to 20MHz / 172.8 Mbps
• Component and device capabilities will be greater than
network capability
• Huge strain on mobile platform design

Transmitter Characteristics – eNB
6.2 Base Station Output Power
6.3 Output Power Dynamics
6.4 Transmit ON/OFF Power
6.5 Transmit Signal Quality
• 6.5.1 Frequency Error
• 6.5.2 Error Vector Magnitude
• 6.5.3 Time alignment between transmitter
branches
6.6 Unwanted Emissions
• 6.6.1 Occupied bandwidth
• 6.6.2 Adjacent Channel Leakage Power Ratio
(ACLR)
• 6.6.3 Operating band unwanted emissions
( same as SEM)
• 6.6.4 Transmitter spurious emission
These transmitter tests are work
in progress and the definitions
and requirements covered in this
presentation are working
assumptions per TR36.804
v1.2.0 & TS 36.104 V8.1.0

Transmitter Characteristics – UE
6.2 Transmit Power
6.4 Control and Monitoring Functions
• 6.5.1 Frequency error
• 6.5.2 Transmit modulation
6.6 Output RF Spectrum Emissions
• 6.6.2 Out of band emission
– 6.6.2.1 Spectrum emission mask (SEM)
– 6.6.2.3 Adjacent channel leakage power ratio (ACLR)
• 6.6.3 Spurious emissions
6.7 Transmit Intermodulation
assumptions per TR36.803
v1.1.0 & TS 36.101 v8.1.0

Output Power Dynamics – eNB
Power control dynamic range
The RE power control dynamic range is
the difference between the power of a RE
and the average RE power for a BS at
maximum output power for a specified
reference condition.
Total power dynamic range
The upper limit of the dynamic range is
the OFDM symbol power for a BS at
maximum output power. The lower limit of
the dynamic range is the OFDM symbol
power for a BS when one resource block is
transmitted. The OFDM symbol shall carry
PDSCH and not contain RS.
Modulation scheme
used on the RE
RE power control dynamic range
(dB)
(down) (up)
QPSK (PDCCH) [-6] [TBD]
QPSK (PDSCH) [-6] [+3 …4]
16QAM [-4] [+3]
64QAM [-0] [+0]
E-UTRA
channel bandwidth (MHz)
Total power dynamic
range (dB)
1.4 [8]
3 [12]
5 [14]
10 [17]
15 [19]
20 [20]

Frequency Error Test
A quick test is use the Occupied
BW measurement (Agilent
89601A VSA SW shown)
An accurate measurement can
then be made using the
demodulation process
If the frequency error is larger
than a few sub-carriers, the
receiver demod may not
operate, and could cause
network interference
The same
source shall be
used for RF
frequency and
data clock
generation.
Minimum Requirement:
–UE: ±0.1 ppm
–Wide Area BS: ±0.05
ppm
–Medium Range and Local
Area BS: TBD

Error Vector Magnitude Measurement
eNB – Downlink (OFDM)
Measurement Block: EVM is
measured after the FFT and a
zero-forcing (ZF) equalizer in
the receiver
BS TX Remove
CP
FFT
Per-subcarrier
Amplitude/phase
correction
Symbol
detection
/decoding
Reference point
for EVM
measurement
Pre-/post FFT
time / frequency
synchronization
Current working assumptions for downlink EVM
limits are:
Parameter Unit Level
QPSK % [17.5]
16QAM % [12.5]
64QAM % [7 to 8]
Signal BW 89650S
(typ)
MXA
(typ)
5 MHz 0.28 % 0.5 %
10 MHz 0.32 % 0.5 %
20 MHz 0.35 % 0.56 %
Agilent Signal Analyzer EVM Performance –
Both Uplink and Downlink
The basic unit of EVM
measurement is defined over one
subframe (1ms) in the time domain
and 12 subcarriers (180kHz) in the
frequency domain

Occupied bandwidth- eNB
Transmission
Bandwidth [RB]
Transmission Bandwidth Configuration [RB]
Channel Bandwidth [MHz]
Resource
block
Channel
edge
Channel
edge
DC carrier (downlink only)
Active Resource Blocks
Channel bandwidth BWChannel [MHz] 1.4 3 5 10 15 20
Transmission bandwidth configuration NRB 6 15 25 50 75 100

ACLR Requirements – eNB case
 Adjacent Channel Leakage power Ratio (ACLR) is the ratio of the
filtered mean power centred on the assigned channel frequency to the
filtered mean power centred on an adjacent channel frequency
 ACLR defined for two cases
• E-UTRA (LTE) ACLR 1 and ACLR 2 with rectangular measurement filter
• UTRA (W-CDMA) ACLR 1 and ACLR 2 with 3.84 MHz RRC measurement filter with
roll-off factor  =0.22.
ACLR limits defined
for adjacent LTE
carriers
ACLR limits defined
for adjacent UTRA
carriers

ACLR Limits – eNB case
TR 36.804 v1.0.0 Table 6.6.2.3-1: Working assumption for BS ACLR for adjacent E-UTRA carriers (paired spectrum)
E-UTRA
Channel BW
(MHz)2
ACLR limit for 1st and 2nd Adjacent channel relative to assigned channel frequency [dB]
UTRA1
5.0 MHz
E-UTRA2
1.4 MHz
E-UTRA2
3.0 MHz
E-UTRA2
5.0 MHz
E-UTRA2
10 MHz
E-UTRA2
15 MHz
E-UTRA2
20 MHz
1.4
ACLR 1 [45] [45] - - - - -
ACLR 2 [45] [45] - - - - -
3.0
ACLR 1 [45] - [45] - - - -
ACLR 2 [45] - [45] - - - -
5
ACLR 1 [45] - - [45] - - -
ACLR 2 [45] - - [45] - - -
10
ACLR 1 [45] - - - [45] - -
ACLR 2 [45] - - - [45] - -
15
ACLR 1 [45] - - - - [45] -
ACLR 2 [45] - - - - [45] -
20
ACLR 1 [45] - - - - - [45]
ACLR 2 [45] - - - - - [45]
NOTES: 1 Measured with a 3.84 MHz bandwidth RRC filter with roll-off factor  =0.22 centered on the adjacent channel.
2 Measured with a rectangular filter with a bandwidth equal to the transmission bandwidth configuration NRB ∙ 180 kHz centered on the 1st or 2nd adjacent channel

Spectrum Emission Mask (SEM)
Operating Band (BS transmit)
10 MHz 10 MHz
Operating Band Unwanted emissions limit
Carrier
Limits in
spurious domain
must be
consistent with
SM.329 [4]
OOB domain
Spectrum emissions mask is also known as “Operating Band Unwanted
emissions”
These unwanted emissions are resulting from the modulation process and
non-linearity in the transmitter but excluding spurious emissions
TR 36.804 v1.0.0 figure 6.6.2.2-1 Defined frequency range for Operating band unwanted emissions with an
example RF carrier and related mask shape (actual limits are TBD).
eNB example:
Base station SEM limits are
defined from 10 MHz below
the lowest frequency of the
BS transmitter operating
band up to 10 MHz above
the highest frequency of the
BS transmitter operating
band.

Spurious Emission Requirements
Spurious emissions are emissions caused by unwanted transmitter
effects such as harmonics emission & intermodulation products but
exclude out of band emissions
Example of spurious emissions limit for a BS
TS 36.104 v8.1.0 Table 6.6.4.1-1: BS Spurious emission limits, Category A
Band Maximum level Measurement
Bandwidth
Note
9kHz - 150kHz
-13 dBm
1 kHz Note 1
150kHz - 30MHz 10 kHz Note 1
30MHz - 1GHz 100 kHz Note 1
1GHz - 12.75 GHz 1 MHz Note 2
NOTE 1: Bandwidth as in ITU-R SM.329 [2] , s4.1
NOTE 2: Bandwidth as in ITU-R SM.329 [2] , s4.1. Upper frequency as in ITU-R SM.329 [2] , s2.5 table 1

Measuring system Set-up
For base station output power, output power dynamics,
transmitted signal quality, Frequency error, EVM, DL RS
power, Unwanted emissions
Measurement
equipment
(Global in-Channel
TX tester)
BS under test

Transmitter Characteristics – UE
6.2 Transmit Power
6.4 Control and Monitoring Functions
• 6.5.1 Frequency error
• 6.5.2 Transmit modulation
6.6 Output RF Spectrum Emissions
• 6.6.2 Out of band emission
– 6.6.2.1 Spectrum emission mask (SEM)
– 6.6.2.3 Adjacent channel leakage power ratio (ACLR)
• 6.6.3 Spurious emissions
6.7 Transmit Intermodulation
assumptions per TR36.803 v
1.0.0 & TS 36.101 v8.1.0

Transmit Signal Quality
UE – Uplink
Currently there are four requirements under the transmit
modulation category for a UE:
1. EVM for allocated resource blocks
2. In-Band Emission for non-allocated resource
blocks
3. I/Q Component (also known as carrier leakage power
or I/Q origin offset) for non-allocated resource blocks
4. Spectrum flatness (relative power variation across
the subcarrier of all RB of the allocated UL block ) for
allocated resource blocks
Let’s look at each one of these transmit modulation requirements…

Error Vector Magnitude Measurement
UE – Uplink (SC-FDMA)
DFT
IFFT
TX
Front-end Channel
RF
correction FFT
Tx-Rx chain
equalizer
In-band
emissions
meas.
EVM
meas.
0
0
…
…
…
IDFT
DUT
Tx
Test equipment
Rx
…
…
…
…
…
…
…
…
…
Modulated
symbols
Measurement Block
   
0
2
'
P
T
v
i
v
z
EVM
m
T
v m





for allocated Resource Block
 
v
z'
 
v
i
is modified signal under test
is the ideal signal reconstructed by the measurement equipment

Error Vector Magnitude Requirements
UE – Uplink
EVM – For allocated resource blocks
• EVM is a measure of the difference between the reference waveform and the
measured waveform
Minimum requirement
For signals above -40 dBm, the RMS EVM for the different modulations must not exceed
the value in the table below
Parameter Unit Level
QPSK % 17.5
16QAM % 12.5
64QAM % [tbd]
•It is not expected that 64QAM will be allocated at the edge of the signal
TS 36.101 v8.1.0 Table 6.5.2.1.1-1: Minimum requirements for Error Vector Magnitude

Occupied Bandwidth Requirement
Occupied bandwidth
Occupied bandwidth is a measure of the
bandwidth containing 99 % of the total
integrated mean power of the transmitted
spectrum on the assigned channel.
Occupied channel bandwidth / channel bandwidth
Channel bandwidth [MHz] 1.4 3.0 5 10 15 20
Nominal Transmission bandwidth
configuration for FDD
6 RB
(1.08 MHz)
15 RB
(2.7 MHz)
25 RB
(4.5 MHz)
50 RB
(9 MHz)
75 RB
(13.5 MHz)
100 RB
(18 MHz)
Minimum Requirement: The
occupied bandwidth shall be less than
the channel bandwidth specified in the
table below

ACLR Requirements – UE case
ACLR defined for two cases:
•E –UTRA (LTE) ACLR1 with rectangular measurement filter
•UTRA (W-CDMA) ACLR1 and ACLR 2 with 3.84 MHz RRC measurement filter with
roll-off factor  =0.22.
E-UTRAACLR1 UTRA ACLR2 UTRAACLR1
RB
E-UTRA channel
Channel
ΔfOOB
TR 36.803 v1.0.0 Figure 6.6.2.2 -1: Adjacent Channel Leakage requirements
The data presented in this slide is still 3GPP working assumptions

Spurious Emission Requirements
Frequency Range Maximum Level Measurement Bandwidth
9 kHz  f < 150 kHz -36 dBm 1 kHz
150 kHz  f < 30 MHz -36 dBm 10 kHz
30 MHz  f < 1000 MHz -36 dBm 100 kHz
1 GHz  f < 12.75 GHz -30 dBm 1 MHz
Spurious emissions are emissions caused by unwanted transmitter effects
such as harmonics emission & intermodulation products but exclude out of
band emissions
Example of spurious emissions limit for a UE
TS 36.101 v8.1.0 table 6.6.3.1-2: Spurious emissions limits

Amplifier Performance - ACLR
LTE QPSK-5MHz 4 carriers
eNB spec -45 dBc
amplifier expectation -55 dBc
desired sig gen -65 dBc
actual sig gen -68 dBc
Mixed LTE QPSK-5MHz / W-CDMA test model 1-64DPCH
eNB spec -45 dBc
actual sig gen -68 dBc adjacent to LTE
-70 dBc adjacent to W-CDMA
LTE 64QAM-20MHz 1 carrier
eNB spec -45 dBc
actual sig gen -71 dBc

Crossing the Analogue-Digital divide

Tools & Using Them Together

Agilent’s Current Measurement Solutions and
Plans for LTE - Commitment
Agilent will provide design and test tools across the R&D
lifecycle
Support for early R&D in components, base station equipment
and mobile devices with design automation tools and flexible
instrumentation, based on current measurement platforms
Refine test solutions and introduce tools for product
integration as development progresses to initial functional
prototypes
Be ready with manufacturing test capability for early ramp-up

Integrated Mobile
Test platform
New Platform for
multiple serial lanes
LTE Products
2006 2007 2008 2009 2010
3GPP LTE
UL/DL Signals
3GPP LTE UL/DL Analysis
and Demodulation
MIMO capability
ADS simulation
SW
Demod
Analysis SW
Signal
Generation
Signal
Analysis
Logic
Analysis
MIPI D_Phy
Commercial Release
Prototype Versions
MXG
MXA
Basic Coded RT
DigRF
89601A VSA
Proto VSA

Page 71
ADS Wireless Library for LTE
Explore and verify your designs
Current Status
• Library of simulation components for the Agilent EESof
Advanced Design System (ADS) to facilitate the generation
and analysis of 3GPP LTE compliant downlink (DL) and uplink
(UL) signals.
• First release Oct 2006. Major updates in Feb 07, May 07,
Sept 07.
• Based on latest physical layer specifications V8.0.0 *Sept 07).
• Generated signals are spectrally correct and encoded, and
can be multi-channel, fixed-length, real-time etc. as required.
• Signals can be exchanged with alternative simulation
platforms, and can be downloaded to, or uploaded from
hardware for real-world signal generation and analysis.
• Received signals can be demodulated and analyzed.
Next Steps
• Continue to follow developments in 3GPP specifications.
Add/evolve signal coding and further develop both DL and UL
transmitter measurements (such as EVM, Constellation etc.).
• Further commercial releases at regular intervals.

Page 72
Advanced Design System Simulation environment
An LTE downlink model in ADS

Page 73
Example here is from IEEE 802.11a/g
ADS “Connected Solutions”
Develop library elements for 3GPP LTE in order to build physical layer
models for both transmitter and receiver in software
Links to test equipment for prototype verification
Implement and deliver a design tool while standard
evolves phased implementation in close cooperation
with customer
Download
Analyze
RF
Component
or DUT

Demodulator
RF IF
Baseband
De-Coding
RF/RF BER
A/D
Converter
I
Q
Where can R&D BER Measurements be Performed?
Simulated Portion of System Design
MXG, ESG
MXA*, PSA
ADS, VSA SW
*Note: Different Analyzer(s) may be used, dependent on required capture depth
Simulated

Demodulator
RF IF
Baseband
De-Coding
RF/IF BER
A/D
Converter
I
Q
MXG, ESG
MXA*, PSA
ADS, VSA SW
Simulated Portion of System Design
*Note: Different Analyzer(s) may be used, dependent on required capture depth
Simulated

Demodulator
RF IF
Baseband
De-Coding
A/D
Converter
I
Q
Simulated Portion of
System Design
MXG, ESG
ADS, VSA SW
RF/Digital IF BER
Logic Analyzer
Simulated
I
Q
I Q

Baseband
De-Coding
Baseband
Encoding
Simulated
Simulated
Digital/Digital BER
ESG + N5102, or Logic Analyzer with
Pattern Generator Board
Logic Analyzers
ADS, VSA SW

Page 78
Digital Serial Stimulus / Analysis
• Current Status
 Introduced DigRF v3 products and solutions
 Bridge gaps between simulation, IC evaluation & handset integration.
 The N4850A & N4860A digital probes designed for 1Gbps
 For LTE digital interfaces that > 1Gbps leverage existing multi GHz
serial technology to support higher speed interfaces.
 Agilent is a MIPI member at Adopter level.
• Next Steps
• Support digital serial stimulus and analysis for
other RF-IC to BB-IC interfaces, integrated
with RF stimulus/analysis, to provide
comprehensive cross domain solutions.
• Review the physical layer specifications for
other (public and vendor-specific) interfaces
between the RF-IC and the BB-IC to guide
LTE specific implementation decisions.
• Agilent is committed to providing test tools for
DigRF v4.0.
N4850A 312Mbps DigRF v3 Digital Serial Acquisition Probe
N4860A 312Mbps DigRF v3 Digital Serial Stimulus Probe

Page 79
BB/RF Interface Stimulus / Analysis Overview
Two modes of operation
Emulation: The stimulus and analysis pods
actively drive and terminate the BB/RF bus, thus
emulating the BB ASIC's interface. The test
equipment provides support for RF ASIC
configuration / control, and drives it with signal
payload data.
Spying: The analysis pod passively monitors the
bus to collect data for further analysis. The test
equipment parses the traffic and presents the
transactions (XML-based protocol viewer) and
payload (89601A Vector Signal Analyzer).
BB ASIC
TEST EQPT
(emulation)
RF ASIC
BB ASIC
TEST EQPT
(spying)
RF ASIC

Page 80
RF-IC Validation (DigRF example)
89601A Vector Signal Analyzer software
RF-IC
Signal Studio Signal Creation Software
N4850A
Acquisition Probe
N4860A
Stimulus Probe
Tx
Rx
16900
Logic Analyzer
MXA Spectrum Analyzer
MXG Signal Generator

89601A VSA Software
DigRF v3 Protocol/Packet
Viewer
The N4850A outputs
34 channels RX and
34 Channels TX,
Signal Ended to the
Logic Analyzer.
N4850A Graphical Part Two: Analysis Probe to LA Interface
Split analyzer-
Tx and Rx can
be running at
completely
different
speeds.

Page 82
RF-IC / BB-IC Integration (DigRF example)
DSP
DigRF
v3.xx
89601A Vector Signal Analyzer
RF
Logic Analyzer Oscilloscope Spectrum Analyzer
RF
BB-IC RF-IC
MXG Signal Generator
Signal Studio
Signal Creation Software
DigRF
uC
DigRF
v3.xx
Vis Port
Digital

SC-FDMA
Page 83
Page 83
Page 83
Signal Studio for LTE
Signal Studio Signal Generator LTE Signal

LTE Signal Analysis
Features/Capabilities Summary
89601A LTE Modulation Analysis: Option BHD

Page 85
LTE Signal Analysis
Downlink Capabilities (based on 36.211 V8.0.0)
• Synchronisation to ADS 2006U1(or U2).407
Dev 1 generated LTE Downlink signals
• Supports Antenna Port 0..3 RS pilot
subcarrier/symbol mappings per TS36.211 OS
and PN9 PRS
• Supports latest PSCH using ZC root indices
25, 29, 34 for cell ID Groups 0, 1, 2
respectively.
• Auto detect / report RS Orthogonal Sequence
• Auto detection of RS PRS
• Latest RS subcarrier antenna mappings
• PDCCH can occupy the first L OFDM symbols
in first slot of subframe, where L<=3.
• User can configure PDCCH symbol
allocations on a subframe-by-subframe
resolution.
• Demod. user specified Slot# and OFDM
symbol#
• User definition of up to 6 PDSCH 2D Data
Bursts for EVM analysis (format QPSK,

Analyzing OFDM impairments using 89601A
This downlink signals
shows a common
OFDM impairment
where the allocated
subcarriers have
an image
The distortion that
create this image was
0.1dB IQ gain
imbalance
The lower trace
shows the increased
EVM at the image
Requirements will be
developed to limit the
image
Allocation Image
EVM by subcarrier

Page 87
LTE Signal Analysis
Uplink Capabilities (based on 36.211 V8.0.0)
• Synchronisation to ADS 2006U1(or
U2).407 Dev1 generated LTE Uplink
signals
• Multiple resource block allocations
restricted to sub carrier DFT sizes which
are multiples of 2, 3 and 5 as per current
3GPP working assumption.
• The DM RS Pilot symbol is located in 4th
symbol (i.e. sym=3) of allocated slots.
• Demodulation of user specified SC-FDMA
symbol# within a Slot of Radio Frame
• Assumes DM RS Pilot symbol contains
Zadoff-Chu Sequence mapped to every
subcarrier within allocated contiguous RB
size.
• User definition of PUSCH two-
dimensional Data Bursts for EVM
analysis (format QPSK, 16QAM, 64QAM)
• Supports Half-Subcarrier-Shift = On/Off
• Uplink frequency lock range approx. +/-

Page 88
LTE Signal Analysis - Measurements
• Sync Correlation
• Freq Error (Hz)
• IQ Offset (dB)
• EVM (%RMS and dB), EVM Peak
(%pk and sub carrier location)
• Data EVM (%rms and dB), EVM
Peak (%pk and sub carrier location)
• Pilot EVM (%rms and dB), EVM
Peak (%pk and sub carrier location)
• Common Pilot Error (%rms)
• Symbol Clock Error (ppm)
• CP Length
• Slot #, Symbol #
• Channel EVM table metrics
– Downlink supports P-SCH, S-SCH,
RS Pilot, PBCH, PDCCH, PDSCH
01 thru 06 (dB, %rms, %pk, Peak
Loc'n)
– Uplink supports DM Pilot, PUSCH
(dB, %rms, %pk, Peak Loc'n)
• Channel Power table metrics
– Downlink supports P-SCH, S-SCH,
RS Pilot, PBCH, PDCCH, PDSCH
01 thru 06 (dB relative to un-
boosted reference)
– Uplink supports DM Pilot, PUSCH
(dB relative to un-boosted reference)

Page 89
LTE Signal Analysis – Trace views
• Channel Freq Response (Adj. Diff Mag Spectral Flatness,
Magnitude, Phase, Group Delay)
• Common Pilot Error (Magnitude, Phase)
• Differential Pilot Error (Timing)
• EVM Spectrum (composite EVM displayed per Sub-Carrier, or per
Resource Block)
• EVM Time (composite EVM displayed per OFDMA/SC-FDMA symbol)
• Power Spectrum (composite Power displayed per Sub-Carrier, or per
Resource Block)
• Power Time (composite Power displayed per OFDMA/SC-FDMA symbol)
• Symbol Demod IQ Constellation/Vector
• Symbol Demod Spectrum Magnitude
• Symbol Demod Time Magnitude
• Symbol Data (Demodulated symbol bits represented as two
hexadecimal characters per sub carrier)

Spectrum Analyzer HW platforms
PSA with 40MHz or 80MHz analysis
BW
• Can be used as RF front end to external PC
where 89601A VSA based LTE application is
running
MXA with 25MHz analysis BW
• Can be used as RF front end to external PC
where 89601A VSA based LTE application is
running

Agilent N5106A PXB
MIMO Receiver Tester
Value Proposition
For R&D engineers developing and integrating MIMO receivers for LTE, WiMAX, and emerging
wireless standards, the N5106A PXB MIMO Receiver Tester simulates real-world conditions to test
beyond standards requirements more quickly and validate design robustness earlier in the
development cycle to minimize design uncertainties and rework.
Designed For Engineers Who Are Doing…
BTS and mobile BB ASIC design validation
RF and BB integration design validation
Co-existence test with multi-format generation
0
Page 91

Agilent N5106A PXB
MIMO Receiver Tester
Industry Leading Baseband Performance
Up to 4 baseband generators (with up to 8 faders)
125 MHz BW & 512 MSa of memory per BBG
Real-time signal creation for receiver test
Support analog and digital IQ outputs
Signal Creation Software
Supports multiple signal creation apps
• LTE, WiMAX, W-CDMA, GSM/EDGE
Fading
Up to 8 real-time faders (with RF in or up to 4 BBGs)
Up to 125 MHz real-time fading BW
Up to 24 paths per fader
Stress devices beyond standard requirements with custom
fading setups to ensure design robustness
MIMO
Up to 4x2 MIMO in one box
Supports MIMO channel models + diversity
Power management and noise calibration
Upgrade to higher order configurations in one hour
Page 92

Page 93
Page 93
N5106A PXB
Transforming MIMO Test
Real-Time Generation
Digital or Analog I/Q outputs
RF outputs
1 Output
1 Output
2 Outputs
2 Outputs

Page 94
Page 94
N5106A PXB
Transforming MIMO Test
MIMO RF Fading
RF in & Digital or Analog I/Q out
RF in & RF out
2x2 MIMO
2x2 MIMO
4x2 MIMO
4x2 MIMO
2x4 MIMO
2x4 MIMO

Page 95
LTE UE Design Flow Solutions
E6620A

Page 96
E6620A
E6620A

Page 97
E6620A
E6620A

Page 98
 Design Validation: Radio and Protocol
 Radio Conformance Test

Page 99
LTE_001 HIT 2008
Agilent Restricted
8/8/2022
FPGA
BB L1/PHY
RF Proto
ASIC Development
BB L1/PHY
RF Chip Dev Design
Validation
Pre-
Conformance
Protocol Development
L2/L3 MAC/RLC
BB
ASIC
RFIC Digital
Interface
Design
Integration
Conformance
Design
Simulation
Manufacturing
LTE Network
Deployment
Network Signaling Analysis
 Just introduced for LTE & SAE
 Enables passive probing & analysis of LTE network
interfaces
 Total visibility for all layers from L1 to L7
 Complete decoding of all protocol messages
J7880A Signaling
Analyzer with J6860A
distributed performance
manager

Agilent 3GPP LTE Portfolio

Agilent LTE Resources:

E6620A Integrated Mobile Test Platform: Specifications
L1 PHY
DSP Engine
PDCP
RLC
MAC
Protocol Processor
UP/DOWN CONV.
20MHz B/W RF
RF I/O
digital I/O
A
P
I
RF I/O
RF I/O*
SISO
MIMO
(2x2 DL)
*Optional 2nd Source/Receiver for 2x2 MIMO
Scalable single box Solution
• 2G/3G/3.9G (LTE) capable
• LTE L1-L2 signalling stack + scripting API
• 20MHz BW
• Data rates up to 100 Mbps DL / 50 Mbps UL
• 2x2 MIMO
• 2 cells
• Digital Baseband Fading
• RF Parametric Measurements
Scripted testcases

Coming
Soon!
Software Solutions
• ADS LTE Design
Libraries
• N7624B Signal Studio
• 89601A VSA Software
Distributed
Network
Analyzers
Conformance Network
Digital VSA
VSA, PSA, ESG, Scope, Logic
R&D
Network Analyzers, Power supplies, and More!
MXA/MXG
R&D
Agilent 3GPP LTE Portfolio
Signalling
Agilent/Anite SAT LTE –
Protocol Development
Toolset
Agilent/Anite SAT LTE – UE Protocol Conformance
Development Toolset
E6620A Wireless
Communications
Platform
Drive Test
Introduced
at MWC
NEW!
Introduced
at MWC
Coming
Soon!

Page 104
Any Questions?

Chipset Interfaces: Analog IQ
Spectrum
Analyzers,
Scopes,
Analog VSAs

Modern Design has the
ADCs placed in the RFIC, -
making the Chip interface
Digital.
Chipset Interfaces: Digital IQ
Digital
VSA/N4850A/N4860A
This was made
possible by
technology changes
in substrates and
electronics.
It makes it much easier to
turn around a BBIC-which
can take months.

The Test & Measurement Challenge
Cross Domain Solutions
RF-IC / BB-IC Integration
RF-IC Validation
BB-IC Turn-on
RF
A/D
A/D
D/A
D/A
IF
Baseband
Digital
RF
A/D
A/D
D/A
D/A
IF
Baseband
Digital
DESER
SER
DESER
SER
Digital Serial IQ + Control
Analog IQ
Evolving To:
Digital
Serial
Was:
Analog
Measurement

LTE Integrated Mobile Test Platform
RLC/MAC interface for protocol test
Full LTE signalling stack
Protocol conformance test
GSM/GPRS, W-CDMA/HSPA
2x2 MIMO
Scalable single box solution
• 2G/3G/3.9G capable
• 20MHz BW
• 2x2 MIMO
• 2 cells
• RF parametric measurements
• Signalling Conformance Test
• RF Conformance Test
initial introduction: Mid-2008
RF conformance test
RF parametric measurements

Agilent LTE Brochure
5989-6331EN
www.agilent.com/find/lte

Concepts of 3GPP LTE.ppt

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