ANALOGUE vs DIGITAL RADIO SYSTEMS Networks for Telemetry Applications.

ANALOGUE vs

DIGITAL RADIO SYSTEMS

ANALOGUE vs

DIGITAL RADIO SYSTEMS

Networks for Telemetry Applications

Where are Data Radio Systems Used?Where are Data Radio Systems Used?

• Wide area networks for machine to machine data communications.Wide area networks for machine to machine data communications.• Remote monitoring and control of industrial systems.Remote monitoring and control of industrial systems.• Remote logging and reporting to SCADA and MES systems.Remote logging and reporting to SCADA and MES systems.• Security and remote access systems. Security and remote access systems.

Telemetry System ModelTelemetry System Model

CONTROLCENTRE

CommunicationsNetwork

SCADA SYSTEM

HUMAN INTERFACE&

DATA MANAGEMENT

MONITORING&

CONTROL

BULKWATERSUPPLY

TELEMETRY NETWORK

SEWAGE&

WASTE

STATUS POINTS&

ALARMS LOGGED DATA&

ALARMS

METERINGSTATIONS

Analogue Radio Network TopologyAnalogue Radio Network Topology

RemoteStation

Radio Modem

RTU

Radio Repeater

RemoteStation

Radio Modem

RTUMaster Station

SCADA

Radio Modem

Distant Stations

Features of Analogue Radio SystemsFeatures of Analogue Radio Systems

• Analogue Radio SystemsAnalogue Radio Systems

– Can cover large distances with repeatersCan cover large distances with repeaters

– Slow over the air data rate – max 1200baudSlow over the air data rate – max 1200baud

– Requires additional interface module between radio and device – Requires additional interface module between radio and device –

Serial to FSK converterSerial to FSK converter

– Radio requires unique alignment for each device interface – Radio requires unique alignment for each device interface –

Cannot just be swapped out on service/replacementCannot just be swapped out on service/replacement

– No management available on radio networkNo management available on radio network

– High maintenance on radios – routine tuningHigh maintenance on radios – routine tuning

– Lower cost of deployment – analogue radios are cheaperLower cost of deployment – analogue radios are cheaper

Digital Radio Network TopologyDigital Radio Network Topology

RemoteStation

Radio Modem

RTU

Radio Repeater

RemoteStation

Radio Modem

RTUMaster Station

SCADA

Radio Modem

Distant Stations

Features of Digital Radio SystemsFeatures of Digital Radio Systems• Digital Radio SystemsDigital Radio Systems

– Can cover large distances with repeatersCan cover large distances with repeaters

– Fast over the air data rate – Fast over the air data rate –

Typically 9600baud but can go up to 19200baudTypically 9600baud but can go up to 19200baud

– Better sensitivity – typical -112dBm @ 9600baudBetter sensitivity – typical -112dBm @ 9600baud

– Does not require additional interface module between radio and device – Does not require additional interface module between radio and device –

Direct Serial or Ethernet interface to the radioDirect Serial or Ethernet interface to the radio

– Radio does not require alignment for device interface – Radio does not require alignment for device interface –

Plug & Play for replacement/servicePlug & Play for replacement/service

– Comprehensive management software for radio networks – Comprehensive management software for radio networks –

Diagnostics, configuration, interface to other environments (SCADA)Diagnostics, configuration, interface to other environments (SCADA)

– No maintenance on radios – no routine tuningNo maintenance on radios – no routine tuning

– Higher cost of deployment – digital radios are more expensiveHigher cost of deployment – digital radios are more expensive

0

500

1000

1500

2000

2500

3000

PreEmp DeEmp PreEmp DeEmp PreEmp DeEmp Data Total

Transmission Stage

Tim

e (m

s)

Analogue @ 1200baud

Digital @ 9600baud

Base Station Repeater #1 Repeater #2

Time of Flight ComparisonTime of Flight ComparisonAnalogue vs Digital Radio

960bits Data Packet

700

300 40

0

200 30

0

100

800

2800

2 2 22 2 2 100

112

Comparison SummaryComparison Summary

Low cost of maintenanceHigher cost of maintenance

Higher cost of deploymentLower costs of deployment

Comprehensive network management toolsNo “in band” remote management

Once off setup, no routine maintenanceRoutine alignment and tuning

Direct interface for Serial/Ethernet devicesRequires additional interface to device

Max 19200baud over the air data rateMax 1200baud over the air data rate

Supports repeater networksSupports repeater networks

Digital RadioAnalogue Radio8 x

Faster