Marconi Academy

MDRS155E – Operation

Module 1 - Introduction

Marconi Academy2 P SR540 E V4.2

Microwave Radio Technology

STM-1/42 Mbit/s

34 Mbit/s

2 Mbit/s34 Mbit/s

STM-1

STM-1

STM-1

STM-1

♦ Free-space propagation of electromagnetic waves

♦ Line of sight connection♦ Frequency range

• 3 to 38 GHz♦ Short-haul and long-haul

systems

Marconi Academy3 P SR540 E V4.2

Microwave Radio Technology

Long-haul system♦ Range

• 15 to 40 km(w/o diversity)

• 40 - >80 km(with diversity)

♦ Frequency range• 3 to 13 GHz

♦ Transmission capacity• 2 to 622 Mbit/s

Short-haul system♦ Range

• up to approx. 20 km♦ Frequency range

• 15 to 38 GHz♦ Transmission capacity

• 2 to 622 Mbit/s

Wave-guide

Indoor Unit

Outdoor Unit

Coaxialcable

Marconi Academy4 P SR540 E V4.2

Microwave Radio Technology - System Designations

Long-haul systems♦ MDRS 155/7500 - 64 QAM

• SDH microwave radio - 7R design♦ MDRS 155/6800 - 64 MLQAM E♦ MDRS 155/13000 - 128 MLQAM E

• SDH microwave radio - ETSI design• Short name: MDRS 155 E

♦ MDRS 2-34/7400 - 16 QAM♦ MDRS 2x34/7400 - 64 QAM

• PDH microwave radio - 7R design

Short-haul systems♦ MDRS 155/18700 - 16 QAM N

• SDH microwave radio - "NKRS"• Short name: MDRS 155 N

♦ MDRS 155/23000 - 16 MLQAM C• SDH microwave radio - "Compact"• Short name: MDRS 155 C

♦ MDRS 155/26000 - 128 MLQAM S• SDH microwave radio• Short name: MDRS 155 S

Marconi Academy5 P SR540 E V4.2

Circulator, Filter(CBN)

WaveguideRF

Circulator, Filter(CBN)

Waveguide

f [GHz]

Channel

BB = Baseband

e.g. 155 Mbit/s

Classical Design

Channel

Demodulator16 - 128 QAM

Modulator16 - 128 QAM

IF = Intermediate frequency

e.g. 140 MHz

RF = Radio frequency

e.g. 7.5 GHz, 18.7 GHz

TXTransmitter

RXReceiver

Marconi Academy6 P SR540 E V4.2

Channel 3

Channel 2

Channel 1

Rx side

RXDMChannel 3

Channel 1

Channel 2

MD

MD

MDChannel 3

Tx side

Channel 1MDTX

Tx side Rx side

DMRXCBNCBNTXMD

DM

DM

DM

RX

RX

RX

Classical Design

TX

TX

TX

f1 f2 f3

f1

f2

f3

f1 f2 f3

Band filter Circulator Absorber

Marconi Academy7 P SR540 E V4.2

f1’f1b

Microwave Radio Technology - Frequency Patterns

f1f1a

CBN CBN

TXMD

DMRX

f1a

f1a

f1a

f1b

DM RX

TX MD

f1b

f1b

f1f1a

f2f2a

f4f4a

f3f3a

f1`f1b

f2`f2b

f4`f4b

f3`f3b

Lower band Upper band

Allocated frequency range

Duplex spacing

Channel spacing

Channel width

Marconi Academy8 P SR540 E V4.2

f1f1a

f2f2a

f3f3a

f5f5a

f4f4a

f6f6a

Hhorizontal

Vvertical

f1f1a

f1f1a

f2f2a

f4f4a

f3f3a

f4f4a

f3f3a

f2f2a

Hhorizontal

Vvertical

90°

Hhorizontal

Frequency Patterns - Transmission via 2 Polarizations

1st polarizationV: vertical

Orthomode

transducer (OMT)

V

TXMD

DM RX

f1a

f1b

CBN

f1

TXMD

DM RX

f1a

f1b

CBN

f1

H

ACDP: Adjacent Channel Dual Polarisation

CCDP: Co- Channel Dual Polarisation

2nd polarization

Marconi Academy9 P SR540 E V4.2

16 QAM

1024QAM512QAM256QAM

128QAM

64QAM

16QAM

4PSK

Se

ns

itiv

ity

Channel width

f1f1a

f2f2a

f4f4a

f3f3a

Channel width

Bandwidth/Channel Width

Channel/bandwidths ♦ Transmission

• SDH

• 155 Mbit/s

♦ 16 QAM • < 45 MHz

• MDRS 155/...- 16 MLQAM

♦ 64 QAM• < 30 MHz

• MDRS 155/...- 64 MLQAM

♦ 128 QAM• < 26 MHz

• MDRS 155/...- 128 MLQAM

The higher the modulation stage ♦ the smaller the channel/

bandwidth (advantage)

♦ the more sensitive to

interference (disadvantage)

64 QAM

128 QAM

Marconi Academy10 P SR540 E V4.2

Frequency Patterns - Channel Spacings

3 4 5 6 7 8 9 1 0 1 1 1 2 1 3

f4f4a

f3f3a

Channelspacing

ITU-R F.382 6 Ch. 29 MHz 3824.5 - 4182.5 MHz

ITU-R F.382 6 Ch. 29 MHz 3413.0 - 3771.0 MHzITU-R F.497 8 Ch. 28 MHz 3422.5 - 3884.5 MHz

ITU-R F.635 7 Ch. 40 MHz 3620 - 4180 MHz

ITU-R F.635* 7 Ch. 40 MHz 3610 - 4170 MHz

ITU-R F.635 4 Ch. 80 MHz 3630 - 4190 MHz

4 (3.6/3.8/3.9 GHz)

ITU-R F.1099 7 Ch. 40 MHz 4430 - 4970 MHz

ITU-R F.1099 4 Ch. 80 MHz 4450 - 4990 MHz 5 (4.7 GHz)

ITU-R F.383 8 Ch. 29.65 MHz 5945.20 - 6404.79 MHzITU-R F.497 8 Ch. 28 MHz 5689 - 6151 MHz

6L (6.2 GHz)

ITU-R F.384 8 Ch. 40 MHz 6460 - 7080 MHz 6U (6.8 GHz)

ITU-R F.385 5 Ch. 28 MHz 7442 - 7708 MHz

ITU-R F.385* 5 Ch. 28 MHz 7428 - 7722 MHz

ITU-R F.385 5 Ch. 28 MHz 7121 - 7429 MHz

ITU-R F.385 5 Ch. 28 MHz 7457 - 7737 MHzITU-R F.385 8 Ch. 28 MHz 7442 - 7883 MHz

7 (7.5 GHz)

ITU-R F.386 8 Ch. 29.65 MHz 7747.70 - 8266.57 MHzITU-R F.386 3 Ch. 28 MHz 8293 - 8468 MHz

8 (8 GHz)

ITU-R F.387 8 Ch. 28 MHz 12765 - 13227 MHz 13 (13 GHz)

ITU-R F.387 12 Ch. 40 MHz 10715 - 11685 MHz

ITU-R F.387 12 Ch. 40 MHz 10695 - 11665 MHz

ITU-R F.387 12 Ch. 40 MHz 10735 - 11665 MHz

11 (11 GHz)

"Free" frequency patterns in Germany

Marconi Academy11 P SR540 E V4.2

40 MHz frequency pattern (e.g. 6.8 GHz)

Channel spacing40 MHz

f1

f1

f2 f4

f3 f4

f3

f2

64 QAM

Channel width30 MHz

Exploitation of Frequency Patterns

f1

f1

f2 f4

f3 f4

f3

f2

128 QAM

28 MHz frequency pattern(e.g. 7.5 GHz or 13 GHz)

f5

f5

f6

f6

f1

f1

f2 f4

f3 f4

f3

f2

26 MHz Channel width

128 QAM

f1

f2

f3 f5

f4 f6

64 QAM

30 MHz Channel width

Channel spacing 28 MHz

Marconi Academy12 P SR540 E V4.2

10 1001 2 5 20 500.01

0.1

1

10

100

dB/km

f/GHz

Rain25mm/h

Rain16mm/h

Rain150mm/h

mm/h (millimeters per hour)

Additional Attenuation

Attenuation due to precipitation ...♦ depends on the intensity

♦ depends on the radio hop length

♦ depends on the frequency

Marconi Academy13 P SR540 E V4.2

218 m

Half-power beamwidth, e.g. ...°

λ

Case 1 + =

λ = wavelength

Case 2 + =

Case 3 + =

Additional Attenuation - Multipath Propagation

e.g. 50 km approx. .... m

Marconi Academy14 P SR540 E V4.2

∆ ∆

Microwave Radio Technology - Space Diversity

DMRX

TX MDCBN

Main

+DMRX

TXMD CBN

Main

+

STM-1 STM-1

CBN

Div

RX

Lengthcompensation

CBN

Div

RX

Marconi Academy15 P SR540 E V4.2

Maximum Radio Hop Lengths

Space Diversity

Climate: Central Europe; BER=2x10E-5; Feeder: 2x30m; w/o Interference; Pout: 0.001%; rain is not considered

0 10 20 30 40 50 60 70 80 90 100

Hop Length / km

MDRS 155/3900-64 MLQAM

With Space Diversity

MDRS 155/4700-64 MLQAM

With Space Diversity

MDRS 155/6200-64 MLQAM

With Space Diversity

MDRS 155/6800-64 MLQAM

With Space Diversity

MDRS 155/7500-64 MLQAM

With Space Diversity

MDRS 155/8000-64 MLQAM

With Space Diversity

MDRS 155/13000-64 MLQAM

With Space Diversity

1.2 m

2 m

3 m

Antennae-

Diameter

Marconi Academy16 P SR540 E V4.2

Microwave Radio Technology - Frequency Diversity

f1a

f3a

f1b

RPS CBNChannel 1

MD TX

MD TX

DM

f3b

RX

RXDM

f1 f3

f

f3f3a

f1f1a

f3’f3b

f1’f1b

Marconi Academy17 P SR540 E V4.2

b 211λ

zone:dst Fresnel ⋅+

Microwave Radio Technology - Fresnel Zone

Radius b

Distance d

Marconi Academy18 P SR540 E V4.2

Microwave Radio Technology - System Designation

3 + 1N

Betriebskanal (BK)Operation Channel (OP)

MErsatzkanal (EK)

Protection Channel (PR)

RPSCBN

STM-1

STM-1

STM-1

DM RX

TXMD

DM RX

TXMD

DM RX

TXMD

DM RX

TXMD

OP1

OP2

OP3

PR

RPS

CBNDM RX

TXMD

DM RX

TXMD

DM RX

TXMD

DM RX

TXMD

STM-1

STM-1

STM-1

OP1

OP2

OP3

PR

CBN

OP1

PR

OP2

OP3

Hhorizontal

Vvertical

OP1 PR

Hhorizontal

Vvertical

OP2 OP3

Marconi Academy19 P SR540 E V4.2

CBN

CBN

System Designation - 3+1 Configuration Example

PR1 TXMD PR1RX DM

RXDMOP1

OP2

OP3

PR1

RXDM

RXDM

RXDM

STM-1

STM-1

STM-1

TX MDOP1

OP2

OP3

PR1

TX MD

TX MD

TX MD

STM-1

STM-1

STM-1

TXMDOP1

OP2

OP3

TXMD

TXMD

STM-1

STM-1

STM-1

RX DMOP1

OP2

OP3

RX DM

RX DM

STM-1

STM-1

STM-1

Occas. traffic (OT)

Occas.traffic (OT)

Occas.traffic (OT) Occas.

traffic (OT)

Marconi Academy20 P SR540 E V4.2

CBN

10dBCBN

1+0 Equipment Protection - "1+1 HSB" Configuration

RPS RPS

f1f1a

f1`f1b

f1a

f1a

TX

TX

Station BStation A

Ch. 1

(STM-1)Ch. 1

(STM-1)

DM RX

f1b

DM RXf1b 10dBOP

PR f1b PR

TX MDf1b

TX MD

OP

OP

PR

MD

MD

RX

f1a

RXf1a

DM

DM

PR

OP

Marconi Academy21 P SR540 E V4.2

1+0 Equipment Protection - Space Diversity

f1f1a

f1`f1b

CBN

Station BStation A

Ch. 1

(STM-1)Ch. 1

(STM-1)RPS RPS

f1b PR

TX MDf1b

TX MD

OP

OP

PR

MD

MDf1a

f1a

TX

TX

CBN

RX

f1a

RXf1a

DM

DM

PR

OP

CBN

CBN

DM RX

f1b

DM RXf1bOP

PR

Marconi Academy22 P SR540 E V4.2

TXMDCh. 1

(STM-1)

DM RX

horizontal f1a

f1b

Ch. 1

(STM-1)

DMRX

TX MD

f1a

f1b horizontal

140MHz

140MHzCBN CBN

Ch. 2

(STM-1)

DMRX

TX MD

f1a

f1b

TXMDCh. 2

(STM-1)

DM RX

vertical

f1a

f1b vertical

140MHz

140MHz

PWPW

CBN CBN

OP2f1

V

f1OP1

f

H

Block Diagram - 2+0 Configuration with XPIC

Clock synchronizationData compensation

V VH H

2 Waveguidepro Station

Marconi Academy23 P SR540 E V4.2

RXTX

HH

MD CBN CBN

RXTX

VV

MD CBN CBN

PW PW

Terms of Microwave Radio Technology - XPIC Principle

H

H + x•V

f

H

V

XPD

XPIC

f

H

V

ATDE

x•V

x•H-x•V

-x•H

V + x•H

ATDE +

ATDE +V

Marconi Academy24 P SR540 E V4.2

Interferences♦ Reason: Interferences on the same channel

Radio hop identifier ♦ prevents the transmission of a co-channel interferer

(e.g due to overlengths)

Terms of Microwave Radio Technology - Identifiers

0001

0010

0011

0100

f1a

f1b

f1a

f1b

f1a

f1b f1b

f1a

Marconi Academy25 P SR540 E V4.2

TX

Terms of Microwave Radio Technology - System Overview

Max. powere.g. +31 dBm

[1.25 W]

Output power

min. powere.g. -73 dBm

[50 pW]

Fadingmargin

Free space attenuation e.g. 143.9 dB

(Distance d = 50 km)(Frequency: f = 7.5 GHz)

( )f[GHz]d[km]log2092.40

a ⋅⋅+=

CBN

waveguide

e.g.5.3 dB

CBNwaveguide

Antenna

gain

e.g.41.4 dB

Antenna

gaine.g.

41.4 dB

CBNwaveguide

CBN

waveguidee.g.

5.3 dB

System attenuation

(e.g. 71.7 dB)

Input power

RX

System gain

Marconi Academy26 P SR540 E V4.2

[ ]

[ ]s Times

bitsrate Data

bits errors MeasuredBER

⋅

=

810072.1

1mins

Mbits155.52

bits100BER:Example −⋅=

⋅

=

Bit Error Ratio (BER)

Radio hopinterference

BER measuringunit

1E-9

1E-8

1E-7

1E-12

1E-11

1E-10

1E-6

1E-5

1E-4

BER

-70 -65 P-75 RX[dBm]

at A

Marconi Academy27 P SR540 E V4.2

Radio hopFailures

caused by various factors

Errored secondsES

0 < BER < 1E-3

Degraded minutes DM

1E-6 < BER < 1E-3

Error-free secondsEFS

BER = 0

Performance

Severely erroredseconds SES

BER > 1E-3(t < 10s)

Transmission Performance

ITU-T G826

> 30% errored blocks(t > 10 s)

< 30% errored blocks

< 30% errored blocks

0% errored blocks

> 30% errored blocks (t<10s)

Unavailable time Available time

Transmission performance of radio hops

Availability

ITU-T G821

BER > 1E-3 (t > 10 s) 0 < BER < 1E-3

Marconi Academy28 P SR540 E V4.2

• ES - (Errored Seconds)• SES - (Severely Errored Seconds)• UT - (Unavailable Time)

(SDH: UAS - Unavailable Seconds)

BER 1E-1 (0.1)

BER 1E-2 (0.01)

BER 1E-3 (0.001)

BER 1E-4 (0.0001)

BER 1E-5 (0.00001)

BER 1E-6 (0.000001)

BER 1E-7

BER 1E-8

BER 1E-9

BER 1E-10

BER 1E-11

t [s]

Transmission Performance

Marconi Academy29 P SR540 E V4.2

Tx side

T´ A´Z´ B´

C´

D´

TXMD

PW

TA ZB

C

D

Rx side

RX DM

PW

Terms of Microwave Radio Technology - Interfaces

T´ - Input Baseband

Z´ - Output Modulator (ZF)

A´ - Output Transmitter

B´ - Output RF Filter (TX)

C´ - Output Circulator (TX)

D´ - Input OMT (TX)

D - Output OMT (RX)

C - Input Circulator (RX)

B - Input RF Filter (RX)

A - Input Receiver

Z - Input Demodulator (ZF)

T - Output Baseband

Marconi Academy30 P SR540 E V4.2

1 1 0 0 0 0 1 1 0 0 0

Clock

Data 0 0 0 0 0

1 1 0 0 0 V 1 1 A 0 0 V A 0 0 V

HDB3

Baseband Code

CMI code♦ CMI - Coded Mark Inversion

♦ Free from DC due to alternating polarity

♦ Used for bit rates > 140Mbit/s• Binary value: log. 0

− first clock half always negative − second edge always positive − always positive rising edge

• Binary value: log. 1− entire clock period alternating with

positive and negative potential

HDB-3 code♦ Modified AMI code

♦ Transmission code for 2, 8 and 34 Mbit/s

• Additional bit V prevents sequences of

more than three log. 0s.

• Additional bit has same polarity as last

data bit.

• If no or an even number of log. 1s

follows two violation bits, an AMI

additional pulse is inserted three bits

before the next violation bit.

1 1 1 0 0 1 0 1 0 1 0

Clock

Data

CMI