Asset Lte - Slides- Robi a1o5y

Asset Tool for LTE by Ishan Marwah 1

© 2012 AIRCOM International Ltd

LTE – Frequency Bands

2

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LTE – Frequency Bands ed 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 ed

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

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LTE – Frequency Bands

4

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

…

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Frame Structures

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LTE – Frame Structure

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Frame Structures -TDD

0

1

2

3

19 10 ms

7

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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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ed 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 ed

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

ed 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

13

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 ed

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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LTE – Carriers

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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

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LTE – Carriers

10mhz

10 Mhz

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LTE - Carriers Bandwidth (MHz) # of RBs Subcarriers

18

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

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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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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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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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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

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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 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 – 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 – 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 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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How AAS 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 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 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

52

-

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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Enabling AAS for LTE Cells • MU-MIMO

• 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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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 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 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 ing Carrier has been assigned to the Service, all UL and DL Bearers will be available for selection as the ing 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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© 2012 AIRCOM International Ltd

Services

After defining the General Service Parameters, one or more Carriers can be related to the Service. Since a ing Carrier has been assigned to the Service, all UL and DL Bearers will be available for selection as the ing 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 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 • • •

• •

•

89

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 s.

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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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© 2012 AIRCOM International Ltd

Simulation – DL Transmission Mode

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© 2012 AIRCOM International Ltd

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 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 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

© 2012 AIRCOM International Ltd

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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© 2012 AIRCOM International Ltd