Data Throughput in CDMA 2000 cellular network

7/28/2019 Data Throughput in CDMA 2000 cellular network

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PROPRIETARY1

Data Throughput in CDMA2000 1X

Dr. Joseph Shapira


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PROPRIETARY2

Throughput

The forward link throughput is limited by the available power.

Link efficiency is the power required to deliver one bit/sec

The power required to support users at location is

;;; rPGGGrErP RTbT

Sector

bitsdtransmitteofNumberThroughputTP

sec

;r

;;; rRrLErP bT Link efficiency

Energy/bit for this service

Data rate

GT,R Antenna gain

PG Path gain (1/path loss)

b

b

R

E

LE


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PROPRIETARY3

Link Efficiency

Efficiency decreases with 4th exponent of the range

Efficiency depends on the antenna pattern

RequiredEb depends on the interference

Eb/It is a set requirement per type of transmission/service

I

C

W

R

I

E b

t

b


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PROPRIETARY4

Throughput is Translated into

Required Eb/It (or C/I) ValuesLatency vs. requiredEb/It

HARQ allows for higher FER and lower Eb/It, but higher latency

Data ratevs. requiredEb/It

Higher data rate requires higher, more sensitive modulation

constellation and less code protection, thus higher Eb/It,

Each Data Transmission Type/ service

has itsEb/Itvs. Max Data-Rate Curve


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PROPRIETARY6

Types of Data Transmission

Conversationallow end-to-end delay, symmetric traffic.Mainly circuit-switched voice services, and (circuit or

packet-switched) video telephony.

StreamingTransmission of data that can be processed as asteady continuous stream. Asymmetric, latency-tolerant.Typical services are web broadcast and video on demand.

InteractiveRequest response pattern. Short round-tripdelay. Typical applications are web browsing, videogames, location-based services.

BackgroundApplications that do not require immediateattention. Starting from SMS, email services and to filestransfer.


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PROPRIETARY7

CDMA2000 FL Configurations

Six forward linkRadio Configurations (RC) are defined for 1x,

- Different length Walsh codes, from 4 to 128 chips, to suit the application.

- QPSK modulation

- Turbo codes

- Fast FL power control (800Hz). There are 1, 0.5 and 0.25 dB steps- Transmit diversity

- Additional channels to accommodate a variety of applications.

- Frame lengths20 ms for signaling and user information, 5 ms for control

information.

- Forward Common Auxiliary Pilot Channel (FCAPiCh), and Forward.

- Dedicated Auxiliary Pilot Channel (FDAPiCh) to support smart antennatransmission


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PROPRIETARY8

Radio Configurations

RC Data rate (Kbps) FEC Encoder rate Modulation TD

1 1.2; 2.4; 4.8; 9.6 1/2 BPSK

2 1.8; 3.6; 7.2; 14.4 1/2 BPSK

3 1.2; 1.35; 1.5; 2.4; 2.7; 4.8; 9.6;

19.2; 38.4; 76.8; 153.6

1/4 QPSK +

4 1.2; 1.35; 1.5; 2.4; 2.7; 4.8; 9.6;

19.2; 38.4; 76.8; 153.6; 307.2

1/2 QPSK +

5 1.8; 3.6; 7.2; 14.4; 28.8; 57.6; 115.2; 230.4 1/4 QPSK +

10 81.6; 158.4; 163.2; 312.0; 316.8; 326.4; 465.6; 619.2;624.0; 633.6; 772.8; 931.2; 1238.4; 1248.0; 1545.6; 1862.4;

2476.8; 3091.2

1/5 QPSK,

8-PSK,

16 QAM


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PROPRIETARY9

FL: Cell Throughput Parameters

Users activity requirements

Distribution of the needs per type within the cell coverage.

This is an operators inputCell resources

Power, channel cards, antenna gain

Cell environmentC/I map. Depends on path-gain, antenna pattern, fading,

diversity, neighboring cells


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PROPRIETARY10

C/I vs. range

for different orthogonality values

-15

-10

-5

0

5

10

15

0.05

0.15

0.25

0.35

0.45

0.55

0.65

0.75

0.85

0.95

1.05

1.15

r/R

C/I[dB]

al=.99 al=.95 al=.7 al=.5 al=al(r)


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PROPRIETARY11

Addressing the Throughput

1. C/I map (by prediction or drive test)

2. Required C/I - Get the required data rate per service typein each location (from operator or audit)

3. By comparing mapsget the max DR per service ineach location

4. Power allocation per service type

5. Integrate power over sector

6. Modify coverage/ service mix to meet power limit

EIRPPilotIEICnP tcBin _*


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PROPRIETARY12

Planning/ Optimization Approach

Divide the cell into bins according to environment and

activity.

Represent average values per bin

Trade-off coverage with max throughput per service per

bin, and service mix, to meet power limit.

Incorporate resource management rules ( vendor

dependent).

Validate by drive test

Monitor over time and change the allocations per actual

activity


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PROPRIETARY13

Throughput Enhancement

Enhance C/I in deficient bins by:

1. Distributed access (repeaters)

2. Polarization matching

3. Beam directivity

4. Transmit diversity5. Load balancing (beam tilt/ shift/ shape)


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PROPRIETARY14

Throughput Validation Methodology

Drive test

Measure C/I ,Ec, Ec/Itmaps

Conduct sessions of each type of data

transmission

Compare with prediction

Calibrate prediction


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PROPRIETARY15

Attention to Resource Management

Each vendor has its resource managementalgorithms:

AOC for controlling power saturation Hashing and channel (FA) transfer for

balancing load and controlling SHO

Etc.These have to be reviewed and incorporated

into the optimization.


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PROPRIETARY16

CDMA2000 1X Rev D RL

- Independent fundamental and supplementalchannels.

- Supplemental R-PDCH (after request and grant)- Scheduler according to data type and link status

- Coherent reverse link with a continuous pilot peruser.

- Frame lengths - 20 ms for signaling and userinformation, 5 ms for control information.

- Adaptive threshold Soft Handoff


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PROPRIETARY17

Noise rise considerations

The noise rise is limitedby max. slope (powercontrol stability).

A data burst shifts thenoise rise.

Admission is based onthe noise rise marginavailable.

This is a policy issue(resource allocation

between services).

Nominal full load

ST dB Max. slope

Data burst


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PROPRIETARY18

Thank YouContact

Dr. Joseph Shapira

PresidentComm&Sens

Tel. +972 4 8251653

Cell +972 54 660708

Email:[email protected]

Date post:	03-Apr-2018
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Data Throughput in CDMA 2000 cellular network

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