good modulation capacity equipment overview

7/26/2019 Good Modulation Capacity Equipment Overview

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Equipment Overview

FT42723EN02GLA3 © 2010 Nokia Siemens Networks

1

Contents

1 Introduction to the Equipment 3

1.1

The FlexiHybrid radio 4

1.2 Ethernet and PDH Common Platform 8

1.3 SDH Mux-Demux capability 11

1.4 RF Operating Bands 12

1.5 Capacity Bandwidth and Modulation (SVR 3.0) 14

1.6 Main Technical Data 19

1.7 Adaptive Power Control 20

1.8 ACM (Adaptive Coding / Modulation) 20

2 FlexiHybrid Applications 27

2.1 FlexiHybrid Network Positioning 27

2.2 Mobile Networks: Access Layer 28

2.3 Mobile Networks: Aggregation layer 29

2.4 Network Example: Tree 30

2.5 Network Example: Hybrid Backhauling 32

2.6 Network Example: Ring 33

Equipment Overview



Equipment Overview

FT42723EN02GLA3

© 2010 Nokia Siemens Networks2



Equipment Overview


3

1 Introduction to the Equipment



Equipment Overview

FT42723EN02GLA3


1.1 The FlexiHybrid radio

The NSN "FlexiHybrid" (FHy) is a point to point microwave radio providing highcapacity transmission, flexibility, a lot of features and convenience for wireless digitalcommunications networks.

It represents a new microwave architecture that is designed to address universalapplications for PDH SDH and Ethernet platforms. This advanced technologyplatform is designed to provide the flexibility to customers for their current and futurenetwork needs. The “FHy” is based upon a common platform to support a wide rangeof network interfaces and configurations. It supports:

• links up to 63xE1,

• 2x10/100BaseTX Ethernet,

• 4x10/100/1000 Base-TX Ethernet,

• 1x1000 Base SX/LX

• 1xSTM-1.

The “FHy” is spectrum and data rate scalable, enabling service providers ororganizations to trade-off system gain with spectral efficiency and channel availabilityfor optimal network connectivity.

The “FHy” enables network operators (mobile and private), government and accessservice provides to offer a portfolio of secure, scalable wireless applications for data,video, and Voice over IP (VoIP).

A microwave terminal is composed of an Indoor Unit (IDU) and one or two OutdoorUnits (ODU) as reported in Fig. 1 and Fig. 2.

Three types of ODU are available: HC AP/CC, HC AP/CC F and HC AP.

– Type HC AP/CC is available within the 6, 7, 8, 11, 13, 15, 18, 23 and 26 GHzbands for AP channeling and implements RF waveguide-connections towards theantenna, and cable-connections (IF) towards the IDU. The mechanicalcompatibility is with the SRAL XD antennas.

– Type HC AP/CC F is available within the 15, 18 and 23 GHz bands for APchanneling and implements RF waveguide-connections towards the antenna, andcable connections (IF) towards the IDU. The mechanical compatibility is with the

FlexiHopper antennas. – Type HC AP is available within the 32 and 38 GHz bands for AP channeling andimplements waveguide-connections (RF) towards the antenna and cable-connections (IF) towards the IDU.

The IDU has been designed to be frequency independent, and the ODU has beendesigned to be capacity independent. The “FHy” allows selection for multiple capacityoptions, modulation types, frequency channels and transmit output power levels toaccommodate and adhere to worldwide regulatory and spectral efficiencyrequirements.

The ODU, mounted outdoor, can support frequency bands from 6 to 38 GHz and can

be directly connected to the rear of antenna by means of four retaining latcheswithout using any waveguide. .



Equipment Overview


5

The following system configurations are available:

• 1+0 unprotected terminal,

• 1+1 Hot Stand-by protected terminal

• 1+1 Frequency Diversity protected terminal

• Add-Drop/ Repeater

• Ring

The “FHy” includes integrated Operations, Administration, Maintenance, andProvisioning (OAM&P) functionality and design features enabling simplecommissioning when the radio network is initially set up in field at the customer’spremises. Furthermore, a highlight of “FHy” is scalability and the capability to supporta ring -type architecture.



Equipment Overview

FT42723EN02GLA3


This ring or consecutive point radio architecture is self-healing in the event of anoutage in the link and automatically re-routes data traffic, thereby ensuring thatservice to the end user is not interrupted.

Figures Fig. 1 and Fig. 2 show the Microwave Split Mount Architecture.

Fig. 1 Example of FlexiHybrid system composition: 1+0 integrated antenna.



Equipment Overview


7

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Fig. 2 Example of FlexiHybrid system composition: 1+1 integrated antenna



Equipment Overview

FT42723EN02GLA3


1.2 Ethernet and PDH Common Platform

Availability of Fast and Giga Ethernet ports, as well as full QoS support andthroughput up to 311 Mbps make FlexiHybrid the best choice for Ethernet backbonebuilt with microwave radios.

Radio

PDHEthernet

Ethernet E1s

Native Ethernet + TDM

:

:XC

X:

Fig. 3 Ethernet and PDH common platform



Equipment Overview


9

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Max

Ethernet

capacity:

311Mb/s

LAN 1

LAN 2

LAN 3

LAN 4

Embedded Switch (with

VLAN tagging and Rapid

Spanning Tree)

QoS: 4

Priority

queues

LAN 5

Flow control

Up to two

radiodirection in

one IDU

ODU HC

AP/CC

(GigE Master IO Unit)

5 x Eth Port:

4x10/100/1000BaseT

1xGbE (SFP)

Fig. 4 Ethernet Gigabit Interface



Equipment Overview

FT42723EN02GLA3




Equipment Overview


11

1.3 SDH Mux-Demux capabili ty

The Mux-Demux option gives the following features:• it provides for a STM-1 Terminal Mux/Demux capability

• It can Mux/Demux up to 63 x E1 from an STM-1 signal

• Performance monitoring via WebGUI

• Only the front-panel STM-1 signal may be routed to the STM-1 Mux/Demux

21 x E1 Optional Input /Output unit is not available with SVR 1.1.

STM-1Mux-Demux

Cross-point Switch

Mini IOOptional IO

unit IO unit

ModemEast

ModemWest

STM-1Up to 16 E1 Up to 16 E1

IDU

Up to 21 E1

Fig. 5 SDH Mux-Demux Capability

WARNINGThe 42xE1 I/O unit associated with the 21xE1 Expansion Optional Unit givesthe possibility to manage up to 63xE1; however this configuration can'tsupport the STM Mini I/O card



Equipment Overview

FT42723EN02GLA3


1.4 RF Operating Bands

Complete Coverage of RF Spectrum5 levels modulation, 7-14-28-56 MHz channel bandwidth

RF Band (GHz)

4QAM, 16QAM, 32QAM, 64 QAM 128QAM

28 MHz

56 MHz

* * 32 QAM, 64QAM, 128QAM

7 8 13 15 18 23 26 28 386 1110

4QAM, 16QAM

4QAM, 16QAM, 32 QAM

14 MHz

7 MHz

Fig. 6 RF Operating Bands

WARNINGOnly 14 and28 MHz channels are supported by SVR 1.1/1.2/1.3/1.4

7 MHz is supported by SVR 2.1/2.2/3.0



Equipment Overview


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-/6L4

-/6L16

-/6L32

6U/6L64

6U/6L128

256

MOD (qam)

5628147BW(Mhz)

6U/6L GHz ODU

4

16

32

64

7,8,11128

256

MOD (qam)

5628147BW(Mhz)

7, 8, 11 GHz ODU

13/26/32/3813/26/32/384

13/26/32/3813/26/32/3816

13/26/32/3813/26/32/3832

13/26/32/3864

13/26/32/38128

256

MOD (qam)

5628147BW(Mhz)

13, 26, 28, 32, 38 GHz

15/18/2315/18/2315/18/234

15/18/2315/18/2315/18/2316

15/18/2315/18/2332

15/18/2364

15/18/23128

256

MOD (qam)

5628147BW(Mhz)

15, 18, 23 ODU

New feature release item

Fig. 7 SVR3.0: Bands, Modulations, Channel bandwidths



Equipment Overview

FT42723EN02GLA3


1.5 Capacity Bandwidth and Modulation (SVR 3.0)

The following tables show capacities, Bandwidth and modulations actually supported.

E1 numberChannel

BandwidthModulation

Ethernet Data

( Mbps)STM-1

0E1 7 MHz QPSK 8 0

0E1 7MHz 16QAM 17 0

0E1 14 MHz QPSK 17 0

0E1 14MHz 16QAM 36 0

0E1 14MHz 32QAM 47 0

0E1 28MHz QPSK 35 0

0E1 28 MHz 16QAM 74 0

0E1 28 MHz 32QAM 95 0

0E1 28 MHz 128QAM 0 1

0E1 28 MHz 128QAM 55 + 100 0

0E1 28 MHz 128QAM 78 + 77 0



Equipment Overview


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E1 numberChannel

BandwidthModulation

Ethernet Data (Mbps)

2E1 7MHZ QPSK 4

2E1 7MHZ 16QAM 13

2E1 14 MHz QPSK 13

2E1 14MHz 16QAM 32

2E1 14MHz 32QAM 42

2E1 28 MHz QPSK 30

2E1 28 MHz 16QAM 70

2E1 28 MHz 32QAM 90

2E1 28 MHz 128QAM 144

4E1 7 MHZ QPSK 0

4E1 7 MHZ 16QAM 9

4E1 14 MHz QPSK 9

4E1 14 MHz 16QAM 28

4E1 14 MHz 32QAM 38

4E1 28 MHz QPSK 26

4E1 28 MHz 16QAM 66

4E1 28 MHz 32QAM 86

4E1 28 MHz 128QAM 136



Equipment Overview

FT42723EN02GLA3


E1 number ChannelBandwidth

Modulation Ethernet Data (Mbps)

8E1 7 MHz 16QAM 0

8E1 14 MHz QPSK 0

8E1 14MHz 16QAM 20

8E1 14MHz 32QAM 30

8E1 28MH QPSK 18

8E1 28MHz 16QAM 57

8E1 28MHz 32QAM 78

8E1 28MHz 128QAM 128

E1 numberChannel

BandwidthModulation

Ethernet Data

( Mbps)

16E1 14 MHz 16QAM 3

16E1 14 MHz 32QAM 14

16E1 28 MHz QPSK 2

16E1 28 MHz 16QAM 41

16E1 28 MHz 32QAM 61

16E1 28 MHz 64QAM 86

16E1 28 MHz 128QAM 112

E1 numberChannel

BandwidthModulation

Ethernet Data

( Mbps)

18E1 14 MHz 16QAM 018E1 14 MHz 32QAM 10

18E1 28 MHz QPSK 0

18E1 28 MHz 16QAM 37

18E1 28 MHz 32QAM 57

18E1 28 MHz 64QAM 82

18E1 28 MHz 128QAM 112



Equipment Overview


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E1 numberChannel

BandwidthModulation

Ethernet Data

( Mbps)32E1 28 MHz 16QAM 8

32E1 28 MHz 32QAM 29

32E1 28 MHz 128QAM 88

42E1 28 MHz 32QAM 8

42E1 28 MHz 128QAM 68

63E1 28 MHz 128QAM 26



Equipment Overview

FT42723EN02GLA3




Equipment Overview


19

1.6 Main Technical Data

Main technical data are reported in Fig. 8.

Technical Data

Fig. 8 Main Technical Data



Equipment Overview

FT42723EN02GLA3


1.7 Adaptive Power Control

FlexiHybrid implements an Adaptive Power Control (APC) architecture where thereceiving Radio continuously measures link metrics (RSL and SNR) and determinesif the link partner’s transmit power needs to be adjusted to maintain link performance.

The Adaptive Power Control algorithm lowers the Tx Power to between the 1E-6 and1E-12 BER level. If SNR or signal-level decreases, the Tx Power is increased tomaintain the 1E-6 BER.

The receiving Station, measures the RSL and SNR once per second, and transmits apower adjustment request to the remote transmitting Station. Once per second TX

side processes the adjustment power requests and increases or decreases transmitpower as requested. If the transmit power is at the limit, an alarm is generated.

The transmit power may be changed in user configurable increments of 1dB to 8dB.

The FlexiHybrid Adaptive Power Control capability is to reduce interference indensely deployed networks.

1.8 ACM (Adaptive Coding / Modulation)

FlexiHybrid Adaptive Coding / Modulation capability (or "ACM", in the following)provides for automatic changes of the link capacity in response to link performance.This capability will help ensure a link is maintained, at reduced capacity, duringdegraded link performance due to weather or other anomalous conditions; on theother hand, at link improvement ACM may allow carrying extra capacity for lowerpriority traffic FlexiHybrid ACM foresees the configuration of three levels, eachassociated to one different mode, which specifies the pattern of modulation, channelspacing and payload mix; of course, the modes selected for the three levels must bethe same channel spacing.

Level1 is always associated to the highest capacity (i.e. highest modulation) mode,

Level2 to the intermediate-capacity mode, and Level3 to the lowest-capacity mode.

After ACM is enabled, it starts at Level1. If the link performance falls below theoperating threshold configured for Level1, ACM automatically switches to Level2.

If the link performance further degrades below the operating threshold configured forLevel2, then ACM automatically switches to Level3.

The user will always have to set three levels. If the user wishes to make the ACMwork with two levels only, the user must set Level2 and Level3 with the same mode.This allows enabling ACM in RF bands and channel spacing combinations whereonly two modulations are supported; for example, the 7 MHz channel spacing (in 15,18 and 23GHz RF bands in SVR 2.1) supports only QPSK and 16 QAM.

Both directions of the link always work at the same ACM level, so each ACM switch



Equipment Overview


21

involves in the same way both directions of the link.

In order to allow automatic reversion from Level3 to Level2 or from Level2 to Level1when link performances improve, the "Revertive switching" mode must be enabled.

Otherwise, if revertive switching is disabled, any switch to higher-capacity levels mustbe done manually by the user, because in this case only switches to lower-capacitylevels are automatic.

If the revertive switching is enabled, ACM will automatically switch either upwards ordownwards among the three levels to ensure the highest capacity for current linkconditions.

At link capacity variation, traffic is prioritized according to the traffic type.

E1 Traffic Prioritization:

If Level2 or Level3 has fewer E1 channels than Level1, higher numbered channels

will be dropped first.For example:

• Level1 supports a 16E1-mode: E1 channels 1 through 16 will be transmitted;

• Level2 supports a 8E1-mode: E1 channels 1 through 8 will be transmitted, while inthis case E1 channels 9 through 16 will be dropped;

• Level3 supports a 4E1-mode: E1 channels 1 through 4 will be transmitted, while inthis case E1 channels 5 through 16 will be dropped.

It is worth nothing here that number of E1 channels should be in descending orderwhile going from Level1 to Level3 [#E1 Level 1 > #E2 Level 2 > #E1 Level 3].

Ethernet Traffic Prioritization:

Ethernet traffic is prioritized by means of QoS. Therefore higher priority Ethernettraffic will be assigned the highest priority when Ethernet capacity is reduced after an ACM switch (e.g. from Level2 to Level3), while lower-priority packets will be morelikely dropped.

• Changes between levels are not hitless, but will cause temporary traffic loss.

ACM is designed so that at ±2 dB/s fading speed the maximum traffic loss will be100 ms for both cases of ACM switches to lower or upper levels. Occasional trafficloss events of some second duration may be allowed.

This 100 msec value is achieved as a sum of (1) 'worst-case' latency of ACMswitch between two sides of the link (2) 'worst-case' re-configuration time and (3)'typical' acquisition time for the modem. Under worst-case modem acquisitionscenarios, this may go higher.

Link quality is monitored through the CER and RM parameters.

• CER. is the Channel Error Rate in the Viterbi decoder, it corresponds to the

rate of mismatches between hard decisions and decoded decisions (Itcorresponds to the "uncoded" BER, not to the BER at the user interface). It isperiodically monitored, and when it rises above a configured threshold, it triggersan ACM switch to the next lower modulation ("down-1-level switch" in the

following).



Equipment Overview

FT42723EN02GLA3


• RM (Revertive Margin). CER is used for down-1-level switches. It cannot be usedalso for switches to the next higher modulation ("up-1-level switch", in thefollowing) since the estimated CER is often 0 when link is good.

Therefore, if "Revertive Switching" is enabled, to allow up-1-level-switching, the"Alpha Flunk" rate (or AF) in the Viterbi decoder is internally considered.

The user can set the desired hysteresis margin to control the revertive switches.

Three capacity levels are provided by FlexiHybrid:

• Level 1: Maximum capacity available

• Level 2: Capacity is reduced when link performancefalls below specified operating thresholds

• Level 3: Capacity is further reduced when linkperformance falls below specified operatingthresholds

Radio link engineering willdetermine the availability of areference capacity level. The targetavailability is calculated using theparameters of the reference

capacity (mainly the threshold).

Level 1

Level 2

Level 3

Fig. 9 Adaptive Modulation



Equipment Overview


23

A defined number of E1 can be

assigned to each Capacity level (the

E1 capacity should be lower or equal

than the max capacity of the level)

n 3

A defined Ethernet Capacity can be

assigned to each level (the ethernet

capacity should be lower or equal

than the max capacity of the level)

c 1

c 2

c 3

Level 1

Level 2

Level 3

TDM traffic

Ethernet traffic

n 1

n 2

n 3

Level 1

Level 3

Level 2

Fig. 10

Capacity

16 QAM

QPSK

32 QAM

64 QAM

128 QAM

The switching criteria is based on two parameters:

1. CER (Channel Error Rate)

2. AF (Alpha Flunk) Estimation of symbol over noise - energy ratio.

Both parameters are dependant from the received signal level andmodulation type

Rx Level

Level 1

Level 2

Level 3

Fig. 11



Equipment Overview

FT42723EN02GLA3


1.8.1 Scope of ACM Applicability

1.8.1.1 Supported Modules

From SVR 2.1 ACM is supported by both the Controller and Controller2 Modules, andby all the Master IO Modules supported in SVR3.0.

1.8.1.2 Supported RF Bands

From SVR 2.1 ACM is supported for the 15, 18 and 23GHz, and within these RFbands, for all supported combinations of channel spacing and modulation, i.e.:

• 7 MHz with QPSK and 16 QAM;

• 14 MHz with QPSK, 16 QAM and 32 QAM;

• 28 MHz with QPSK, 16 QAM, 32 QAM, 64 QAM and 128 QAM.

1.8.1.3 Supported Modes

All modes with the same bandwidth can be used to configure the ACM levels with thefollowing constraints:

• two modes with the same bandwidth and modulation but with different payload mixcannot be used as different ACM levels; in other words, different ACM levelsrequire modes with different modulations;

• as the AF indicator does not allow revertive switching from QPSK to 64 QAM orfrom QPSK to 128 QAM, then QPSK and 64 QAM, or QPSK and 128 QAM will notbe allowed as adjacent ACM levels;

• Level1, Level2, and Level3 must be associated to the highest, intermediate, andlowest modulation, respectively; moreover the number of E1 channels should be indescending order while going from Level1 to Level3 [#E1 Level 1 > #E2 Level 2 >#E1 Level 3];

• modes with STM-1 payload transport (i.e. mode #139 from SVR 2.1) cannot beconfigured for ACM configuration;

• modes with Ethernet "Plus" mode (i.e. modes #140 and #141 from SVR 2.1)cannot be configured for ACM configuration;

• the possible modes combinations released in SVR 3.0 are listed in Fig. 12



Equipment Overview


25

Fig. 12 Released configurations for ACM in SVR 2.1

1) 16QAM at Level 3 is also allowed, QPSK has been certified because of is theworst condition.

2) The value medium or High in this case are critical because they can cause thesystem to not return to the higher level.

WARNINGIn East/East configuration the following limitations are present:

– when the ACM is switching it can happen that the changes in Ethernetpayload throughput in the two directions (from one NE to the other) are notsimultaneous (one direction can show some delay in reaching the finalEthernet rate with respect to the other);

– occasionally the Ethernet payload can be lost for about 30s;

– ACM switch in one radio affects also the payload in the other radio;

– when the Mux/Demux option is present the ACM switch causes the

activation of STM1 alarms.



Equipment Overview

FT42723EN02GLA3


1.8.2 ACM Configuration Parameters

The User can enable or disable ACM and to enable or disable the revertive switching

when ACM has been enabled.

CER and RM thresholds for down- and up-1-level switching are not configurable bythe user (they are fixed). The CER threshold (for down-1-level switches) is selectedaccording to the following strategy: It provides the minimum distance from theBER=10-6 (at the user interface) that guarantees the ACM maximum switch time (i.e.that prevents the modem unlocking) with the declared fading speed.

This strategy aims at:

• avoiding the long switching times (typically than 2 seconds) that occur when areceiver unlocks;

•

employing a higher mode as long as possible before switching to a lower one. Infact, if ACM is disabled, a mode will be working until it reaches its BER=10-6threshold; therefore, if ACM is enabled, that same mode should be used until itsBER is as close as possible to its 10-6 threshold.

According to this strategy, from SVR 2.1 the proper CER threshold is fixed to 10-6.The revertive margin for the up-1-level switches guarantees a proper hysteresis forthe revertive switching. Hysteresis margin reduces the chance of frequent changesbetween modulations; furthermore it prevents unstable conditions of the ACM loop,when ACM could be indefinitely bouncing between two levels even if link conditionsare stable (e.g. after some fading activity).

The revertive margin is selected according to the following strategy:

• providing the lowest hysteresis margin that prevents ACM levels bouncing. This isaimed at raising the probability of an up-1-level switch, i.e. of higher throughput,when the link conditions improve.

The quality parameter AF used in SVR2.1 for the up-1-level switching does

not make it possible to properly control the revertive margin within aspecified range (e.g. 3 dB ±1dB) for all the RF bands.

Furthermore, for each ACM level the following parameters can be configured bythe user:

• ACM Switch Delay. This delay is configurable in the range 1÷2 seconds with a

granularity of ½ second. This parameter contains a delay value that describes thetime between 2 samples for CER polling: it is necessary that two CER samples,one "ACM Delay Switch" seconds after the other, cross the CER threshold beforethe down-1-level switch procedure is initiated. Of course, ACM Delay Switch is nota configuration parameter of Level3.

• Revertive Switch Delay. This value is configurable only if revertive switching hasbeen enabled, in the range 1÷2 seconds with a granularity of ½ second. This delayrefers to the time between consecutive polling actions of the AF threshold: it isnecessary that two AF samples, one "Revertive Delay Switch" seconds after theother, cross the AF threshold before the up-1-level switch procedure is initiated. Of

course, Revertive Delay Switch is not a configuration parameter of Level1.



Equipment Overview


27

2 FlexiHybrid Applications

2.1 FlexiHybrid Network Positioning

Fig. 13 shows the FlexiHybrid Network Positioning:

• first aggregation

• aggregation

FirstAggregation

InternetInternet

Tail

Aggregation

Backbone

1st Aggregation

Aggregation

1st Mile

Fig. 13 FlexiHybrid Network Positioning



Equipment Overview

FT42723EN02GLA3


2.2 Mobile Networks: Access Layer

FlexiHybrid can also be used inside the Access Layer as reported in Fig. 14

Fig. 14 FlexiHybrid inside the Access Layer

• Up to 311 Mbps Ethernet throughput

• Hybrid backhauling

• Ring protection for data and TDM traffic



Equipment Overview


29

2.3 Mobile Networks: Aggregation layer

FlexiHybrid inside the Aggregation Layer is reported in Fig. 15

Regional

Fiber/MW SDH ring

STM-4/16

End Site

End Site

End Site

MW SDH ring

1,2 x STM-1

NodeB

End Site

End Site

End Site

N x E 1 + E t h

MxE1+Eth KxE1+Eth

N x E

1 + E t h

MxE1+Eth

NxSTM-1+Eth

Regional

Fiber/MW SDH ring

STM-4/16

End Site

End Site

End Site

MW SDH ring

1,2 x STM-1

NodeB

End Site

End Site

End Site

N x E 1 + E t h

MxE1+Eth KxE1+Eth

N x E

1 + E t h

MxE1+Eth

NxSTM-1+Eth

Fig. 15 FlexiHybrid inside the Aggregation Layer

• E1, Ethernet Mixed Traffic Interfaces

• Hybrid backhauling



Equipment Overview

FT42723EN02GLA3


2.4 Network Example: Tree

•

Tree Network Example are reported in Fig. 16 and Fig. 17

62xE1

30xE1

16xE1

16xE1 SDH

Support of high PDH capacity (up to 63 E1)

in the Root link

Two directions in the same IDU

(Add/drop functionality)

62xE1

FlexiHybrid

2x(1+0)

32xE1

30xE1

16xE1

16xE1

FlexiHybrid

FlexiHybrid

STM-1

Fig. 16 Tree Network Example (1)



Equipment Overview


31

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16xE1

32xE1 4xE1

local

SDH

Link protection

52xE1

16xE1

16xE1Unprotected MW link

Protected MW link

STM-1 channelized interface to reduce

cabling and interconnections

FlexiHybrid 1+1

FlexiHybrid 1+1

STM-1

(32xE1)

16xE1

4xE1

52xE1

16xE1

32xE1

FlexiHybrid 1+0

STM-1

FlexiHybrid 1+1

Fig. 17 Tree Network Example (2)



Equipment Overview

FT42723EN02GLA3


2.5 Network Example: Hybrid Backhauling

Hybrid Backhauling example is shown in Fig. 18.

Tail Site

Hub Site

Fiber/Aggregation Hub Site

Unprotected MW link

Protected MW linkFlexi BTS

Node B

IDUs are connected in order to

act as a HUB

4xE1 + 20Mbps12xE1 + 60 Mbps

FlexiHybrid (1+1)

FlexiHybrid (2+0)

GE

STM1(8xE1)

4xE1 + 20Mbps

4xE1 + 20Mbps

GE 140Mbps

STM-1 (28xE1)

FlexiHybrid (1+1)

GE 12xE1

12xE1 + 60Mbps

12xE1 + 60Mbps

4xE1 + 20Mbps

Fig. 18 Network Example: Hybrid Backhauling



Equipment Overview


33

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2.6 Network Example: Ring

FlexiHybrid in Ring configuration is shown in Fig. 19 and Fig. 20.

16/32/42/63 E1

Eth

Flexibility: wide range of configuration

and number of access interfaces

Ring node with one IDU

w/o external equipment (ADM,Switch)

PDH ring protection

Ethernet ring protection (Rapid

Spanning tree)

FlexiHybrid

Fig. 19 Ring Configuration (1)



Equipment Overview

Fig. 20 Ring Configuration (2)

good modulation capacity equipment overview

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