motorola rnp 1 mcch throughput

8/12/2019 Motorola RNP 1 MCCH Throughput

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General Business Information

MOTOROLA and the Stylized M Logo are registered in the US Patent & Trademark Office.All other product or service names are the property of their respective owners. Motorola, Inc. 2006.

Mission Critical Radio Network Planning

- Part I

Jens Jakobsen

Senior Systems Architect


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General Business InformationMOTOROLA and the Stylized M Logo are registered in the US Patent & Trademark Office.

All other product or service names are the property of their respective owners. Motorola, Inc. 2006.

Slide 3

TETRA Systems

MSO

MSO

MSO

Inter-MSO

Link

Key Features Group calls

Call priority

Security

Reliability

Dedicated capacity

TETRA: Terrestrial Trunked Radio - formerly known as Trans European Trunked Radio


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Slide 4

What are we Planning for?

Reliabili ty and Availability

99.7%, 99,98% or 99.999% availability?

Resilience to earthquakes, flooding or power outages?

Fallback operation Radio Coverage

Indoor handheld, outdoor or outdoor vehicle coverage?

Geographical coverage

Group and Individual Call Quality Call blocking probability

Call drop probability

Call setup latency

Audio quality and delay

Packet and Short Data Quality Bit-rate

Packet loss

Delay and jitter


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Slide 5

Reliability Features

Redundancy

Network elements

Communication links

Geographical redundancy

Fallback Modes

Base station can operate independently of MSO

Direct mode operation between mobiles


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Slide 6

Failure Mode and Effects Analysis

Steps to perform an FMEA

1. Review the design.

2. Brainstorm potential failuremodes.

3. List potential effects of failure.

4. Assign Severity Numbers

5. Assign Occurrence Numbers

6. Assign Detection Numbers

7. Calculate the Risk Priority Number

8. Develop the Action Plan

FMEA standards.

MIL-STD-1629A: Military Standard

Procedures for Performing a FailureMode, Effects and Criticality

Analysis

http://www.fmeainfocentre.com/dow

nload/MILSTD1629.htm ECSS-Q-30-02A: Space

Q.9000 ISO/CD20827: Automotive

IEC 60812: Electro-technical

Prior to step 1 there is a step involving protocol establishment and planning of the exercise
http://www.fmeainfocentre.com/download/MILSTD1629.htmhttp://www.fmeainfocentre.com/download/MILSTD1629.htmhttp://www.fmeainfocentre.com/download/MILSTD1629.htmhttp://www.fmeainfocentre.com/download/MILSTD1629.htm


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Slide 7

Reliability Engineering

Series Components

Parallel Components

A1 =MTBF1

MTBF1 + MTTR1

1

2

1 2

A2 =MTBF2

MTBF2 + MTTR2

A = 1 - (1- A1) * (1-A2)

A1 =MTBF1

MTBF1 + MTTR1

A2 =MTBF2

MTBF2 + MTTR2

A = A1 * A2

Reference: Patrick D. T. OConner Practical Reliability Engineering, p 129


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Slide 8

Call Profile

Group Individual and Telephony Calls

Call arrival rate per subscriber

Call duration Number of participating base stations per group call

Number of inter-MSO calls

Grade of service

Packet Data

Traffic rate per subscriber (uplink/downlink)

Short Data

Short data arrival rate per subscriber (uplink/downlink)

Mobility Management

Cell re-select rate per subscriber


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Reference: Frantisek Ginzl, City Radio System City of Prague, Tetra World Congress 2005.


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Slide 10

Base Station Capacity Planning

Base Station Subscribers Erlang Channels Tranceivers

1 15 0.75 4 2

2 30 1.50 6 2

3 120 6.00 13 4

4 90 4.50 11 3

5 90 4.50 11 3

6 15 0.75 4 2

7 25 1.25 5 2

Using Erlang B. GoS/Blocking = 0.01. Each subscriber generates 5 milli-Erlang. Each TRX is 4 timeslots.


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Slide 11

Inter-MSO link Capacity Planning

Do the Erlang magic on voice calls

Matrix with busy hour traffic load foreach MSO-MSO pair

Add packet, short data and networkmanagement

Matrix with busy hour traffic load foreach MSO-MSO pair

Apply routing protocol to determine

traffic load of each link Such as MSO1-MSO4 path is through

MSO2.

Apply agreed link failures to obtain

needed failover capacity Such as one concurrent link failure

Result: Required Inter-MSO bandwidth

Inter-MSO

Link

MSO

1

Inter-MSO

LinkMSO

2

MSO

3

MSO

4


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Slide 12

Main Control Channel Capacity Planning

Main Control Channel

Power-on registrationsCell re-select

Call setup / teardown

Short data messagesPacket data control

Timeslots

Frequency 3Frequency 2

Frequency 1 3 2 1 0

7 6 5 411 10 9 8

Main Control Channel (MCCH)


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Slide 13

ALOHA Throughput

Reference: Andrew Tanenbaum, Computer Networks, third edition, Prentice-Hall 1996, Figure 4-3

Tetra has 34 random accessopportunities per second.

Max throughput: ~ 13 msg/s


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Reference: Deputy Chief Constable Ricky Gray, G8 Summit, Tetra World Congress 2005.Reference: Deputy Chief Constable Ricky Gray, G8 Summit, Tetra World Congress 2005.


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Reference: Deputy Chief Constable Ricky Gray, G8 Summit, Tetra World Congress 2005.Reference: Deputy Chief Constable Ricky Gray, G8 Summit, Tetra World Congress 2005.Reference: Deputy Chief Constable Ricky Gray, G8 Summit, Tetra World Congress 2005.


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Slide 17

Recursive Network Planning

MSO

Network

Configuration

Fault

Management

Performance

Statistics

Accounting

Records

Network

Management

Subscriber

Provisioning

motorola rnp 1 mcch throughput

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