Asset Tool User for LTE by Ishan Marwah 1
© 2012 AIRCOM International Ltd
LTE – Frequency Bands
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© 2012 AIRCOM International Ltd
LTE – Frequency Bands Supported Channels (non-overlapping) E-UTRA Band
* X -
3
Downlink Bandwidth
Channel Bandwidth (MHZ)
1.4 3 1 60 2 60 42 20 3 75 53 23 4 45 32 15 5 25 17 8 6 10 7 70 25 8 35 11 9 35 10 60 11 25 12 18 12 6 13 10 7 3 14 10 7 3 ... 33 20 34 15 35 60 42 20 36 60 42 20 37 20 38 50 39 40 40 100 UE receiver sensitivity can be relaxed Channel bandwidth too wide for the band Not supported
5 12 12 15 9 5 2 14 7 7 12 5 3* 2* 2*
10 6 6 7 4 2* 1* 7 3* 3 6 2* 1* 1* 1*
15 4 4* 5* 3 X 4 2* 4 1* X X
20 3 3* 3* 2 X 3* 1* 3 1* X X X
4 3 12 12 4 10 8 -
2 1 6 6 2 5 4 10
1 1 4 4 1 3 6
1 X 3 3 1 2 5
© 2012 AIRCOM International Ltd
LTE – Frequency Bands
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E-UTRA Band
Bandwidth UL (MHz)
E-ARFCN UL
Bandwidth DL (MHz)
E-ARFCN DL
Duplex Mode
1
1920-1980
13000 – 13599
2110-2170
0 – 599
FDD
2
1850-1910
13600 – 14199
1930-1990
600 - 1199
FDD
3
1710-1785
14200 – 14949
1805-1880
1200 – 1949
FDD
4
1710-1755
14950 – 15399
2110-2155
1950 – 2399
FDD
5
824-849
15400 – 15649
869-894
2400 – 2649
FDD
6
830-840
15650 – 15749
875-885
2650 – 2749
FDD
7
2500-2570
15750 – 16449
2620-2690
2750 – 3449
FDD
8
880-915
16450 – 16799
925-960
3450 – 3799
FDD
9
1749.9-1784.9
16800 – 17149
1844.9-1879.9
3800 – 4149
FDD
10
1710-1770
17150 – 17749
2110-2170
4150 – 4749
FDD
11
1427.9-1452.9
17750 – 17999
1475.9-1500.9
4750 – 4999
FDD
12
698-716
18000 – 18179
728-746
5000 – 5179
FDD
13
777-787
18180 – 18279
746-756
5180 – 5279
FDD
14
788-798
18280 – 18379
758-768
5280 – 5379
FDD
...
…
…
…
…
33
1900-1920
26000 – 26199
1900-1920
26000 – 26199
TDD
34
2010-2025
26200 – 26349
2010-2025
26200 – 26349
TDD
35
1850-1910
26350 – 26949
1850-1910
26350 – 26949
TDD
36
1930-1990
26950 – 27549
1930-1990
26950 – 27549
TDD
37
1910-1930
27550 – 27749
1910-1930
27550 – 27749
TDD
38
2570-2620
27750 – 28249
2570-2620
27750 – 28249
TDD
39
1880-1920
28250 – 28649
1880-1920
28250 – 28649
TDD
40
2300-2400
28650 – 29649
2300-2400
28650 – 29649
TDD
…
© 2012 AIRCOM International Ltd
Frame Structures
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© 2012 AIRCOM International Ltd
LTE – Frame Structure
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Frame Structures -TDD
0
1
2
3
19 10 ms
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Frame Structures -TDD
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Frame Structures -FDD
10 ms 0
1
2
One Sub-frame = 1 mS 9
3
19 In half-duplex FDD operation, the UE cannot transmit and receive at the same time, while there are no such restrictions in full-duplex FDD © 2012 AIRCOM International Ltd
Frame Structures - FDD
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LTE Carriers
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Supported Channels (non-overlapping)
LTE Carriers
E-UTRA Band
Since the appropriate LTE Frequency Band and LTE Frame Structure have been selected or defined then the Carriers can be defined
* X -
12
Downlink Bandwidth
Channel Bandwidth (MHZ)
1.4 3 1 60 2 60 42 20 3 75 53 23 4 45 32 15 5 25 17 8 6 10 7 70 25 8 35 11 9 35 10 60 11 25 12 18 12 6 13 10 7 3 14 10 7 3 ... 33 20 34 15 35 60 42 20 36 60 42 20 37 20 38 50 39 40 40 100 UE receiver sensitivity can be relaxed Channel bandwidth too wide for the band Not supported
5 12 12 15 9 5 2 14 7 7 12 5 3* 2* 2*
10 6 6 7 4 2* 1* 7 3* 3 6 2* 1* 1* 1*
15 4 4* 5* 3 X 4 2* 4 1* X X
20 3 3* 3* 2 X 3* 1* 3 1* X X X
4 3 12 12 4 10 8 -
2 1 6 6 2 5 4 10
1 1 4 4 1 3 6
1 X 3 3 1 2 5
Bandwidth (MHz)
1.4
3
5
10
15
20
# of RBs
6
15
25
50
75
100
Subcarriers
72
180 300 600 900 1200 © 2012 AIRCOM International Ltd
Supported Channels (non-overlapping)
LTE Carriers
E-UTRA Band
Since the appropriate LTE Frequency Band and LTE Frame Structure have been selected or defined then the Carriers can be defined
* X -
Assign Carrier to Frequency Band
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Downlink Bandwidth
Channel Bandwidth (MHZ)
1.4 3 1 60 2 60 42 20 3 75 53 23 4 45 32 15 5 25 17 8 6 10 7 70 25 8 35 11 9 35 10 60 11 25 12 18 12 6 13 10 7 3 14 10 7 3 ... 33 20 34 15 35 60 42 20 36 60 42 20 37 20 38 50 39 40 40 100 UE receiver sensitivity can be relaxed Channel bandwidth too wide for the band Not supported
5 12 12 15 9 5 2 14 7 7 12 5 3* 2* 2*
10 6 6 7 4 2* 1* 7 3* 3 6 2* 1* 1* 1*
15 4 4* 5* 3 X 4 2* 4 1* X X
20 3 3* 3* 2 X 3* 1* 3 1* X X X
4 3 12 12 4 10 8 -
2 1 6 6 2 5 4 10
1 1 4 4 1 3 6
1 X 3 3 1 2 5
Bandwidth (MHz)
1.4
3
5
10
15
20
# of RBs
6
15
25
50
75
100
Subcarriers
72
180
300
600
900
1200
© 2012 AIRCOM International Ltd
LTE – Carriers
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© 2012 AIRCOM International Ltd
LTE – Carriers
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© 2012 AIRCOM International Ltd
LTE – Carriers
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E-UTRA Band
Bandwidth UL (MHz)
E-ARFCN UL
Bandwidth DL (MHz)
E-ARFCN DL
Duplex Mode
1
1920-1980
13000 – 13599
2110-2170
0 – 599
FDD
© 2012 AIRCOM International Ltd
LTE – Carriers
10mhz
10 Mhz
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© 2012 AIRCOM International Ltd
LTE - Carriers Bandwidth (MHz) # of RBs Subcarriers
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1.4 6 72
3 15 180
5 25 300
10 50 600
15 75 900
20 100 1200
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LTE – Carriers R0 R0 R0 R0
R0 R0 R0 R0
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R0 R0 R0 R0
R0 R0 R0 R0
R0 R0 R0 R0
R0 R0 R0 R0
R0 R0 R0 R0
R0 R0 R0 R0
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LTE – Carriers R 1 R0 R 1
R0
R0
R 1 R0
R 1
R 1
R0 R 1
R0
R0
R 1 R0
R 1
Configuration of Carrier- 2 antenna
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Configuration of Carrier - 1 Antenna
R0
R0
R0
R0
R0
R0
R0
R0
Specific pre-defined resource elements (indicated by R0-3 in in the time-frequency domain) are carrying the cell-specific reference signal sequence.
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Downlink reference signal structure The downlink reference signal structure is important for channel estimation. The principle of the downlink reference signal structure for 1 antenna. Ref Signal TX1 = 8 for 15Khz spacing
© 2012 AIRCOM International Ltd
Configuration of Carrier- 2 Antennas
R1
R0
R0
R1
R1
R1
R0
R1
R1 R0
R0
R0
R1
R0
R0
R1
Downlink reference signal structure The downlink reference signal structure is important for channel estimation. The principle of the downlink reference signal structure for 2 antenna. Ref Signal TX2= 16 for 15Khz spacing
Specific pre-defined resource elements (indicated by R0-3 in in the time-frequency domain) are carrying the cell-specific reference signal sequence.
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© 2012 AIRCOM International Ltd
Configuration of Carrier- 3 Antennas
R1
R0
R0
R2
R1
R1
R1
R1
R2
R1
R0
R1
R0
R0
R0
R2
R2 R0
R0
R1
Specific pre-defined resource elements (indicated by R0-3 in in the time-frequency domain) are carrying the cell-specific reference signal sequence.
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Downlink reference signal structure The downlink reference signal structure is important for channel estimation. The principle of the downlink reference signal structure for 2 antenna. Ref Signal TX3= 20 for 15Khz spacing
© 2012 AIRCOM International Ltd
Configuration of Carrier- 4 Antennas
R1
R0
R3
R2
R0
R1
R1 R3
R1
R2
R0
R3
R1
R2
R0
R0
R2
R1
R0
R1
R0
R0
R3
R1
Downlink reference signal structure The downlink reference signal structure is important for channel estimation. The principle of the downlink reference signal structure for 2 antenna. Ref Signal TX3= 20 for 15Khz spacing
Specific pre-defined resource elements (indicated by R0-3 in in the time-frequency domain) are carrying the cell-specific reference signal sequence.
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Type1-DL Frame
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FDD Frame Structures UL Type1-FDD- Uplink UL Control Channel PUCCH transmission in one subframe is compromised of single PRB at or near one edge of the system bandwidth followed by a second PRB at or near the opposite edge of the bandwidth PUCCH regions depends on the system bandwidth. Typical values are 1, 2, 4, 8 and 16 for 1.4, 3, 5, 10 and 20 MHz UL Signals(S-RS & DM RS) S-RS estimates the channel quality required for the UL frequency-selective scheduling and transmitted on 1 symbol in each subframe DM-RS is associated with the transmission of UL data on the PUSCH and\or control signalling on the PUCCH Mainly used for channel estimation for coherent demodulation Transmitted on 2 symbols in each subframe 26
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Type1 - UL Frame
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© 2012 AIRCOM International Ltd
Setting the Overhead Parameters • After you have set the frequency parameters in the LTE Carriers dialog box, you can set the parameters on the Overhead tab. This tab enables you to define the associated fixed and variable signalling and control channel overhead of each carrier.
• LTE Frames are two-dimensional (time and frequency) entities, containing
various signalling and control channels. Each of these signals/channels occupy a certain amount of Resource Elements (REs) in both the uplink and downlink. In the downlink, the amount of occupied resources for certain channels also depends on the number of transmit antennas deployed.
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Site Data Base
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ECGI
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Bearers
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LTE – Bearers
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© 2012 AIRCOM International Ltd
LTE – Bearers
Downlink
The Default Uplink and Downlink LTE bearers are defined per CQI providing 15 DL bearers and 4 UL bearers.
Uplink
CQI is a report sent from the UE to the eNodeB suggesting the appropriate Modulation and Coding to be used by the eNodeB. 33
© 2012 AIRCOM International Ltd
Channel Quality Indicator Reporting Each default Bearers has Control & Traffic SINR requirements according to
PDSCH
PUSCH
PUCCH
CQI Report The UE may not have PUSCH resources 34
CQI
Modulation
Actual coding rate
Required SINR
1
QPSK
0.07618
-4.46
2
QPSK
0.11719
-3.75
3
QPSK
0.18848
-2.55
4
QPSK
308/1024
-1.15
5
QPSK
449/1024
1.75
6
QPSK
602/1024
3.65
7
16QAM
378/1024
5.2
8
16QAM
490/1024
6.1
9
16QAM
616/1024
7.55
10
64QAM
466/1024
10.85
11
64QAM
567/1024
11.55
12
64QAM
666/1024
12.75
13
64QAM
772/1024
14.55
14
64QAM
873/1024
18.15
15
64QAM
948/1024
19.25 © 2012 AIRCOM International Ltd
Channel Quality Indicator Reporting 15 Default Bearers
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CQI
Modulation
Actual coding rate
Required SINR
1
QPSK
0.07618
-4.46
2
QPSK
0.11719
-3.75
3
QPSK
0.18848
-2.55
4
QPSK
308/1024
-1.15
5
QPSK
449/1024
1.75
6
QPSK
602/1024
3.65
7
16QAM
378/1024
5.2
8
16QAM
490/1024
6.1
9
16QAM
616/1024
7.55
10
64QAM
466/1024
10.85
11
64QAM
567/1024
11.55
12
64QAM
666/1024
12.75
13
64QAM
772/1024
14.55
14
64QAM
873/1024
18.15
15
64QAM
948/1024
19.25 © 2012 AIRCOM International Ltd
Bearers
S is the average received signal power, I is the average interference power, and N is the noise power. 36
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TDD
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TDD
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Uplink Bearers
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Uplink UL 64QAM
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Uplink UL 64QAM
SINR=+12.75
UL 16QAM
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Uplink
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Limiting the Service Area
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Limiting Service area to 1Km
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MIMO
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Single User MIMO Principle 4 Closed-loop spatial multiplexing Here the UE reports both the RI and index of the preferred pre-coding matrix.
Spatial Multiplexing does increase throughput but this comes at an expense of higher SINR requirements as shown on the LTE bearers
Rank Indicator (RI) is the UE’s recommendation for the number of layers, i.e. streams to be used in spatial multiplexing. RI is only reported when the UE is operating in MIMO modes with spatial multiplexing 46
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Multi User – MIMO MU-MIMO is used to increase the cells’ throughput. This is achieved by co-scheduling terminals on the same Resource Blocks.
Spatial Multiplexing does increase throughput but this comes at the expense of higher SINR requirements, as shown on the LTE bearers 47
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Multi User – MIMO Applying MU-MIMO will make no obvious changes to a network unless it is overloaded In order for MU-MIMO to be used, there is a higher Traffic & Control SINR requirement defined
Spatial Multiplexing does increase throughput but this comes at the expense of higher SINR requirements, as shown on the LTE bearers 48
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MU-MIMO
MU-MIMO increases cell throughput and number of terminals 49
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Single User MIMO Principle Spatial Multiplexing does increase throughput but this comes at the expense of higher SINR requirements as shown on the LTE bearers
SU-MIMO
SU-MIMO Tx Diversity
This is the coverage area for SU-MIMO +22dB 50
Roughly speaking, Diversity is used to improve coverage DLRS SNR © 2012 AIRCOM International Ltd
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© 2012 AIRCOM International Ltd
How AAS Support Affects Simulations Cell in Site Database (AAS Settings tab)
Look-Up Table (Tab Name)
SU-MIMO - Diversity (downlink) SU-MIMO - Diversity (uplink) SU-MIMO - Multiplexing (downlink)
DL SD SINR Adjustment UL SD SINR Adjustment DL SM Rate Gain
DL SD SINR Adjustment UL SD SINR Adjustment DL SM Rate Gain Adjustment
-
-
DL SM SINR Offsets
SINR Delta for SUMIMO
Required SINR is adjusted by the specified delta value.*
UL SM Rate Gain
UL SM Rate Gain Adjustment
-
Achievable User Data Rate is multiplied by the corresponding table value.*
-
UL SM SINR Offsets
-
DL MU-MIMO SINR Offsets and
SU-MIMO - Multiplexing (uplink)
SU-MIMO - Adaptive Switching (uplink and/or downlink)** MU-MIMO (uplink and/or downlink)**
Clutter Parameters MIMO SINR Delta (Column name) Offset on Bearer
-
Required DL SINR is divided by the corresponding table value.* Required UL SINR is divided by the corresponding table value.* Achievable User Data Rate is multiplied by the corresponding table value.*
SINR Delta for SURequired SINR is adjusted by the MIMO specified delta value.* All or any of the above, depending on channel conditions, and/or the cell-specific thresholds, if enabled.
UL MU-MIMO SINR Offsets
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-
How a Simulation of Network Performance is Affected
SINR Delta for MUMIMO
The number of served terminals is increased by the factor specified in the Average Co-scheduled Terminals. Also, Required SINR is adjusted by the specified delta value on the bearer.*
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Order of AAS Modes in the Simulator AAS Modes Enabled
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Sequence Attempted by Simulator
Sequence Attempted by Simulator if Cell-specific MIMO Threshold(s) are Enabled
SU-MIMO Adaptive Switching
1. SU-MIMO Multiplexing
If Adaptive SU-MIMO RS SNR threshold is enabled:
2. SU-MIMO Diversity
SU-MIMO Multiplexing is employed above the threshold, and then SU-MIMO Diversity below the threshold.
SU-MIMO Diversity and MU-MIMO
1. MU-MIMO
If MU-MIMO RS SNR threshold is enabled:
2. SU-MIMO Diversity
MU-MIMO is employed above the threshold, and then SUMIMO Diversity below the threshold.
SU-MIMO Multiplexing and MU-MIMO
1. SU-MIMO Multiplexing
If MU-MIMO RS SNR threshold is enabled:
2. MU-MIMO
SU-MIMO Multiplexing is employed above the threshold, and then MU-MIMO below the threshold.
SU-MIMO Adaptive Switching and MU-MIMO
1. SU-MIMO Multiplexing
If Adaptive SU-MIMO RS SNR and MU-MIMO RS SNR thresholds are enabled:
2. MU-MIMO
3. SU-MIMO Diversity
Initially, SU-MIMO Multiplexing is employed above the Adaptive SU-MIMO RS SNR threshold, then MU-MIMO is employed above the MU-MIMO RS SNR threshold, and finally SU-MIMO Diversity is employed. © 2012 AIRCOM International Ltd
AAS Settings in Site DB
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© 2012 AIRCOM International Ltd
Enabling AAS Support for LTE Cells • MU-MIMO Support
• This is an example of the MU-MIMO settings:
• For the downlink and/or uplink, you can set the Average Co-scheduled Terminals, a factor that can increase the number of served terminals.
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How do we set this up in ASSET?
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Bearers - LTE Parameters
Above this threshold switch to SU-MIMO If enabled Below this threshold switch to SU-MIMO Diversity
SU-MIMO
SU-MIMO Diversity
+22dB 57
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DL Transmission Mode
Switches on DLRS SNR 58
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Services
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© 2012 AIRCOM International Ltd
Introduction QoS differentiation (i.e. prioritisation of different services according to their requirements) becomes extremely important when the system load increases The most relevant parameters of QoS classes are: • Transfer Delay • Guaranteed Bit rate Delay sensitive QoS Classes have guaranteed bit rate requirements.
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Services When running a simulation, ASSET first attempts to serve the GBR demands of both Real Time and Non-Real Time services, taking into account the Priority values of the different services.
Allocation and Retention Priority (ARP)
Resources are first allocated to the service with the highest priority, and then to the next highest priority service, and so on.
If resources are still available after the GBR demands have been met, then different scheduling algorithms can be employed to attempt to serve the MBR of real time services. 62
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LTE QoS
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LTE Services – Bearer Selection Method
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Services
No carrier defined OR BEARER
When running a simulation, ASSET first attempts to serve the GBR demands of both Real Time and Non-Real Time services, taking into account the Priority values of the different services.
After defining the General Service Parameters one or more Carriers can be related to the Service. Since a supporting Carrier has been assigned to the Service, all UL and DL Bearers will be available for selection as the Supporting Bearers. 65
© 2012 AIRCOM International Ltd
Services
A Minimum Bit Rate (Min-GBR) and a Maximum Bit Rate (Max-MBR) have been specified for the service. If a terminal achieves connection to one or more of the available bearers, the eNodeB will firstly allocate enough resources to it in order to achieve Min-GBR.
It will keep allocating more resources to it until the terminal either reaches the Max-MBR ceiling, or until there not more resources available due to cell loading.
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LTE – Bearers
The Default Uplink and Downlink LTE bearers are defined per CQI providing 15 DL bearers and 4 UL bearers. The most preferable bearer is DL-CQI-15 and the least preferable bearer is DL-CQI-1
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Services
The Default Uplink and Downlink LTE bearers are defined per CQI providing 15 DL bearers and 4 UL bearers
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Services
The Default Uplink and Downlink LTE bearers are defined per CQI providing 15 DL bearers and 4 UL bearers
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Services
After defining the General Service Parameters, one or more Carriers can be related to the Service. Since a supporting Carrier has been assigned to the Service, all UL and DL Bearers will be available for selection as the Supporting Bearers.
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Terminal Types
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Terminal Types
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Terminal Category
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Terminal Types
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Terminal Types
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Terminal Types
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Traffic Raster
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Packet Scheduler
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Packet Scheduler If resources are still available after the GBR demands have been met, then different scheduling algorithms can be employed to attempt to serve the Max Bit Rate.
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Packet Scheduler
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Round Robin Scheduler UE 1 Data Request
UE 2 Data Request
UE 6
UE 5
UE 1 Data sent
UE 2 Data sent
UE 3 data Request
UE 4
UE 3 Data sent
UE 4 Data Request
UE3
UE 4 Data sent
UE 5 Data Request
UE 2
UE 5 Data sent
The aim of this scheduler is to share the available/unused resources equally among the RT terminals
UE 1 UE 6 Data sent
UE 6 Data Request
NodeB Buffers
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NodeB Packet Scheduler
The Round Robin approach is completely random, as it simply allocates the same resources to all terminals in turns © 2012 AIRCOM International Ltd
Proportional Fair If resources are still available after GBR demands have been met:
• Terminals with higher data rates get a larger share of the available resources
• Each terminal gets either the resources it needs to satisfy its RT-MBR demand or its weighted portion of the available/unused resources, whichever is smaller
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Proportional Demand If resources are still available after the GBR demands have been met: The aim of this scheduler is to allocate the remaining unused resources to RT terminals in proportion to their additional resource demands.
Proportional Demand completely ignores RF conditions
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Max SINR Terminals with higher bearer rates(and consequently higher SINR) are preferred over terminals with lower bearer rates (and consequently lower SINR). This means that resources are allocated first to those terminals with better SINR/channel conditions, thereby maximising the throughput.
where S is the average received signal power, I is the average interference power, and N is the noise power.
Best RF conditions are served first.
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Max SINR Own-signal interference in LTE an occur due to :
• Inter-symbol interference due to multipath power exceeding cyclic prefix length
• Inter-carrier interference due to Doppler spread (large UE speed) In LTE, orthogonality is often assumed unity for simplicity:
a = 1 is assumed for LTE and hence Iown = 0. where S is the average received signal power, I is the average interference power, and N is the noise power.
Best RF conditions are served first. 85
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Simulating Network Performance
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Monte Carlo-Based Simulation When simulating network performance, ASSET uses Monte Carlo algorithms, which can provide a good balance between accuracy and usability.
The Simulator can be used as Full simulation, with randomised snapshots, or Simulation without snapshots. With full simulation, the performance of the network can be analysed over a series of randomised snapshots, in which specified densities of user terminals are positioned in statistically determined locations. The ability of each terminal to make its connection to the network is calculated through an iterative process. The performance of the network is then analysed from the averaged results.
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Simulation with Snapshots • Takes a large number of randomised snapshots of network performance for different terminals over time
• In these snapshots, the UEs are in statistically determined positions and generated independently for each snapshot
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Simulation with Snapshots • Terminal count in a pixel is determined using a Poisson distribution with a • • •
• •
•
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mean given by the number of terminals in the traffic array At the start of the snapshot, the mobile and cell powers are initialised to zero to initialise the noise on the uplink and downlink Other parameters, such as power control error, are set randomly on UE The first terminal in the list is tested for failure conditions. If it does not fail, then its Tx power and the Tx power of the cells to which it is connected, are modified. The next terminal in the list is then tested for failure conditions, and so on. When the entire list has been tested, the simulator returns to the first terminal and repeats the process until convergence is reached When convergence is reached, the results of the snapshot are appended to the results of the overall simulation. The simulation moves on to the next snapshot When the simulation has completed all the specified snapshots, you can view your results using the arrays or view a summary of the data or reports
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LTE Simulator Wizard
Choose your specified output
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Simulation without Snapshots • If you run a simulation without running snapshots (static analysis), you must ensure that the cell loading parameters for the cells/sectors have been specified in the Site Database
• The parameters are set on the Cell Load Levels subtab, under LTE Params tab
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Simulator Outputs • ASSET provides ways of setting your own array
definitions so that you can specify exactly which arrays you want to be output when you use the Simulator
• The easiest way is to use the Auto Setup option. This
ensures that all the relevant array types and their parameter combinations are included in the simulation outputs for display and analysis.
• You can also define your own customised collection of
output array types from the Simulator. This enables you to specify array definitions to determine precisely which arrays you want to output and display, in any combination of parameters you choose. This method is probably only beneficial for advanced users.
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Auto Setup Option Make the required selections for EXCLUSION from the output arrays.
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Customised Output
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Simulation – Best RSRP
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Simulation – RSRQ
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Simulation Report
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Simulation – Cell Centre / Cell Edge
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Simulation – Achievable DL Bearer
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Simulation – DL RS SINR
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Simulation – DL Transmission Mode
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Pixel Analyser The Pixel Analyser visualises detailed signal strength information that has been accumulated during a simulation.
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Information about Simulated Terminals • The aim of this feature is to provide the user with a set of arrays that
show the locations of terminals generated by the simulation snapshots, and to show whether the terminals succeeded or failed to make a connection. The following arrays are provided for each terminal type used in the simulation. •
Terminal Info: Failure Rate
•
Terminal Info: Failure Reason
•
Terminal Info: Speed
• The arrays are only available in simulations that run snapshots, and
where the user has checked the Allow Terminal Info Arrays box on the 2nd page of the simulation wizard.
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Information about Simulated Terminals Failure Reason array. 1 snapshot
Failure Reason array. 500 snapshots
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PCI Planning
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Introduction to PCI planning • Physical layer Cell Identity (PCI) identifies a cell within a network equivalent of UMTS scrambling code • There are 504 Physical Layer Cell Identities compared to 512 UMTS scrambling codes PCI are organised in 168 groups of 3 codes compared to 64 groups of 8 for UMTS scrambling codes
Physical layer Cell Identity = (3 × Group(0 to 167)) + Code 0-2
Id = 0 Id = 2
Id = 6 Id = 8
Cluster Group Id = 1 Id = 3
Id = 5
Id = 9
Id = 11 Id = 4
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Id = 7
Id = 10 © 2012 AIRCOM International Ltd
Physical Cell Identity (PCI)
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LTE PCI Schemas
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PCI planner In PCI planner you can specify a re-use distance from any cell which the planner will try not to assign the same PCI. Two methods:
Fixed This is a constant re-use distance from a cell, within which the planner will try not to assign the same PCI Automatic This is a variable re-use distance from a cell, within which the will try not to assign the same PCI
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Physical layer Cell Identity
Physical layer Cell Identity = (3 × Group(0 to 167)) + Code 0-2 = (3 x 2) + 2 =8
Group(0 to 167) Code (0-2)
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Minimising Groups. Physical layer Cell Identity = (3 × Group(0 to 167)) + Code 0-2
PCI=0
PCI=1
PCI=2
PCI=3
PCI= 4
PCI= 5
Group =0
Group =0
Group =0
Group =1
Group =1
Group =1
Code =0
Code =1
Code =2
Code =0
Code =1
Code =2
Carrier 1 PCI=0
Carrier 1 PCI=2
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Carrier 1 PCI=1
ONLY TWO GROUPS USED
Carrier 1 PCI=3
Carrier 1 PCI=4
Carrier 1 PCI=5
© 2012 AIRCOM International Ltd
Frequency shifts PCI =0
PCI =0
PCI =0
PCI =6
PCI
GRO UP
CO DE
CELL SPECIFIC FREQ SHIFT
0
0
0
0
1
0
1
1
2
0
2
2
3
1
0
3
4
1
1
4
5
1
2
5
6
2
0
0
CELL SPECIFIC FREQ SHIFT This determines the DLRS pattern (time frequency positions)
PCI =1
PCI =7 PCI =0
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PCI =0
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Minimising Groups. Physical layer Cell Identity = (3 × Group(0 to 167)) + Code 0-2
PCI=0
PCI=1
Group =0
Group =0
Code =0
Code =1
FREQ SHIFT FREQ SHIFT =0 =1
PCI=2 Group =0 Code =2
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Group =1 Code =0
PCI= 4 Group =1 Code =1
Carrier 1 PCI= 1
PCI= 5 Group =1
FREQ SHIFT FREQ SHIFT FREQ SHIFT =2 =3 =4
Carrier 1 PCI=0
Carrier 1PCI=2
PCI=3
Code =2
FREQ SHIFT =5
Carrier 1 PCI=3
PCI
GRO UP
CO DE
CELL SPECIFIC FREQ SHIFT
0
0
0
0
1
0
1
1
2
0
2
2
3
1
0
3
4
1
1
4
5
1
2
5
6
2
0
0
CELL SPECIFIC FREQ SHIFT This determines the DLRS pattern (time frequency positions)
Carrier 1PCI=4
Carrier 1 PCI= 5
© 2012 AIRCOM International Ltd
Minimising Codes.
PCI=0 Group =0 Code =0
PCI=6 Group =2 Code =0
FREQ SHIFT FREQ SHIFT =0 =0
PCI=9 Group =3 Code =0
PCI=12 Group =4 Code =0
PCI= 15
PCI= 18
Group =5 Code =0
Group =6 Code =0
FREQ SHIFT FREQ SHIFT FREQ SHIFT =3 =0 =4
FREQ SHIFT =0
Carrier 1 Carrier 1
PCI=0
PCI=12
Carrier 1 PCI=9
Carrier 1 PCI=6
Carrier 1 PCI=15
Carrier 1 PCI=18
PCI
GRO UP
CO DE
CELL SPECIFIC FREQ SHIFT
0
0
0
0
1
0
1
1
2
0
2
2
3
1
0
3
4
1
1
4
5
1
2
5
6
2
0
0
7
2
1
1
8
2
2
2
9
3
0
3
10
3
1
4
11
3
2
5
12
4
0
0
13
4
1
1
14
4
2
2
15
5
0
3
16
5
1
4
17
5
2
5
18
6
0
0
Very poor PCI planning 114
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Using a planning tool
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Very poor DLRS SINR
© 2012 AIRCOM International Ltd
Thank You
[email protected]
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