ALC1

ALC PDH RADIOTechnical Training

Instructor

Mr. Monthien Satantoranin

Senior Manager Technical Support

ALC2

Training TopicsTraining Topics

1. ALC Equipment Structure2. Installation , Configuration and Operating3. SCT Network Management4. Faults and Alarm Understanding5. Troubleshooting and Looback Test6. Path/Link Calculation

ALC3

ALC Equipment StructureALC Equipment Structure

1. ALC IDU ( Indoor Unit)2. ALC ODU ( Outdoor Unit)3. LIM ( Line Interface Module)4. RIM ( Radio Interface Module)5. Interconnection IDU to ODU cable

ALC4

Mains FeaturesMax capacity : 16 E1 + 3 Ethernet PortIDU size: 1U high only and single boardService channel: optional V11 codirectional. Loops: RF loop, IF loop and Baseband loopsATPC range : depending on frequency (20dB or 40 dB)Internal PRBSIDU-ODU cable: 370 meter of ¼” or RG8

IDU ( Indoor Unit)

ALC5

IDU (Indoor Unit)IDU (Indoor Unit)

21

RXTX

ALTEST

R

USER IN/OUTQ3 LCT

Trib. 13-14-15-16Trib. 5-6-7-8

Trib. 9-10-11-12Trib. 1-2-3-4

PS2

PS1

212

48V2

+ --+

48V1

Fuse: 3.15A (M)

IDU-ODU cable SMA connectors

120ohm E1 Sub-D type connectorsLCT USB

connector

SCT LAN port

PSU alarm LEDs

PSU connector

Tx Rx

1

2

TEST

ALR

Active branch (Tx / Rx)

Manual operation / Loop active

AlarmsReset

ALC6

ODU (Outdoor Unit)ODU (Outdoor Unit)

Volt/dBm in Rx

Reference Tooth

Weight = 4.5 Kg

ALC7

ODU Mounting ODU Mounting

Max.1 dB Loss

ALC8

ALC9

Unprotected ODU

1+1 ODU

1+0 ODU

ODUODU with with Integrated antennaIntegrated antenna

ALC10

Frequency signals:Tx IF 330 MHzRx IF 140 MHzTelemetry IDUODU 17.5 MHzTelemetry ODUIDU 5.2 MHzPower 48 VDC

Max length (1/4 inch or RG 8 cable)4/16QAM 370 m

Interconnection cableInterconnection cable

ALC11

Equipment CompositionEquipment Composition

ALC is made up by different sub-modules housed in two mechanical structures:

1) IDU LIM Controller RIM (one per branch)

2) ODU Radiotransceiver (RT, one per branch)

ALC12

Module functionalitiesModule functionalities

Service interfaces

Management software ports

Equipment controller

EOC

Alarm LEDs

User in / Alarm out facilities

Power supplyCable interfaceModulator (analog side) 330 MHzDemodulator (analog side) 140 MHz

Radio Power supply

Cable interface

IF unit

RF unit: Transmitter, Receiver

Line interfaces

Line Mux-Demux circuits, Service Mux-demux circuits

Bit insertion-extraction,

Modulator - Demodulator (digital side)

Switch management

BER counters

LIM

CONTROLLERRIM

RT

ALC13

Equipment Equipment structurestructure

ALC14

ControllerController

ALC15

LIM LIM Tx directionTx direction)

ALC16

LIM LIM Rx directionRx direction

FEC *

(block code)

errors

*FEC = Forward Error Corrector

Example: Without BER=10-6

With BER=10-13 (+2.5 dB)

ALC17

RIMRIM

ALC18

ODUODU

ALC19

ALALCC characteristics (1) characteristics (1) Tx power (4QAM/16QAM): 7 GHz +27 dBm / +22 dBm 15 GHz +25 dBm / +20 dBm 23 GHz +20 dBm / +15 dBm Tx/Rx spacing: 7 GHz 154/161/168/196/245 MHz 15 GHz 420/728 MHz 23 GHz 1008/1232 MHz Power consumption 1+0 < 30 W 1+1 < 55 W

ALC20

ALC characteristics (2) Rx HBER (10E-3) thresholds (4QAM/16QAM): - in 16x2 7 GHz -84 dBm / -80 dBm 15 GHz -83.5 dBm / -79.5 dBm 23 GHz -83 dBm / -79 dBm - in 4x2 7 GHz -90 dBm / -86 dBm 15 GHz -89.5 dBm / -85.5 dBm 23 GHz -89 dBm / -85 dBm Max Rx power - 20 dBm

ALC21

Installation ,Configuration andInstallation ,Configuration andOperatingOperating

1. IDU, ODU Installation2. SCT :Network Management Software3. LCT :Local Craft Terminal4. Parameter and Configuration5. Alarm Monitoring 6. Backup ,Upload and Download firmware

ALC22

Installation

IDU InstallationPower Supply and GroundingE1 Cable and WiringAntenna and ODU Mounting

ALC23

Installation

IDU Installation (1)USB/LCT

E1

Power Supply

IDU to ODU

Cable

ALC24

Installation

IDU Installation (2)

IDU to ODU Cable

ALC25

InstallationPower Supply and Grounding

Power Supply

-48 to -57.6 Vdc

Nominal Consumption

44 watts (1+0)

24 watts ( IDU only)

ALC26

InstallationPower Supply and Grounding

1= IDU grounding point 5=IDU matching tail grounding

2=ODU grounding point 6=Battery grounding point

3= IDU-ODU interconnect cable 7=Grounding cord connect to Earth ground rod

4=Cable grounding/Station ground

ALC27

InstallationODU Grounding

ALC28

Installation

E1 Cable and Wiring

ALC29

Installation

Antenna and ODU Mounting

ALC30

Installation

Antenna and ODU Mounting

ALC31

InstallationAntenna and ODU Mounting

ALC32

Installation

Antenna and ODU Mounting

ODU final housing position for

Vertical Polarization

ODU final housing position for

Horizontal Polarization

ALC33

Antenna and ODU mounting1 2 3

4 5 6

ALC34

SCT/LCT : Main Features SCT/LCT connection SCT Main Window Menus Routing Stored Routing Table Station management Commang Logger Equipment features management Configuration backup/restore Alarm monitoring LCT Main Window Manus Radio Parameter Configurations

ALC35

SUBNETWORK and LOCAL SUBNETWORK and LOCAL CRAFT TERMINALCRAFT TERMINAL

SCT/LCTSCT/LCT

PERSONAL COMPUTER WITH GRAPHICAL DISPLAYPERSONAL COMPUTER WITH GRAPHICAL DISPLAY

WINDOWS 98, NT, 2000, XP SW PLATFORMWINDOWS 98, NT, 2000, XP SW PLATFORM

TCP/IP COMMUNICATION PROTOCOL USING:TCP/IP COMMUNICATION PROTOCOL USING: RS232 Serial port (COM1/2 + PPP)RS232 Serial port (COM1/2 + PPP) USB +PPPUSB +PPP Ethernet LAN Ethernet LAN

ALC36

““ALC” RADIO IP PROTOCOL STACKALC” RADIO IP PROTOCOL STACK

TCP / UDP

LLC 802.2MAC 802.3

802.3(ETH LAN)

IP / OSPF

ASYN-RS23257.6Kb/s

APPLICATION SOFTWARE

SNMP

EOC (Radio)64Kb/s

P P P

LCTUSB

ALC37

SCT : Connections

C

ALC38

Connection to the equipmentConnection to the equipment

ALC39

Login

User: SYSTEM (read & write) ; RLOM (read only)

Password: siaemicr

ALC40

History log

Equipments inside the stationStations

ALC41

Log as SYSTEM an equipment in monitor

Read again the status of the equipment

User management and time alignment Configuration

upload/download and station management

History log

management

Configuration of the equipment

list of commands

Configuration of the connection

ALC42

SCT Menu-EquipmentSCT Menu-Equipment

ALC43

SCT Menu-OptionSCT Menu-Option

ALC44

SCT Menu-NetworkSCT Menu-Network

ALC45

SCT Menu-ToolSCT Menu-Tool

ALC46

Equipment menuEquipment menu Equipment configuration

Agent, name, time

Alarms, group by group

Alarms’ configuration

Test, loops, manual operations

Firmware update

Performance monitoring

Units

Automatic troubleshooting

Alarms reading (refresh)

Routing and addressing

ALC47

ALC48

PropertiesPropertiesEquipment name

Agent, used in alarm history and in subnetwork wizard

Equipment time alignment and network time alignment

Software restart (doesn’t cut the traffic)

ALC49

View Current AlarmsView Current Alarms

ALC50

Alarm configurationAlarm configuration

ALC51

Manual operations listManual operations list

ALC52

Firmware UpdateFirmware UpdateFirmware Switch

Download of the firmware

Upload of the actualfirmware

ALC53

Download of the new firmwareDownload of the new firmware

Position of the file firmware.dwl

Overwriting of old firmware (total dowload – slow)

Download of different sections only (fast) or towards peripheral (radio)

Bench switch after the download

ALC54

Performance MonitoringPerformance Monitoring

Quality results

Output power

Input power

Start/Stop of selected item

Show of the resultsof the selected item

ALC55

UNITS

Status

Part number Part number

Kind of troubleTrouble severity

ALC56

DiagnosisDiagnosis

Reading the actual alarms the Diagnosis prepares an explanation of every trouble and the procedures to follow to solve the problem

ALC57

Port addressesPort addressesAll SIAE equipments, regarding SCT software and supervision, are routers: all interfaces need an address and relevant subnet mask

Addresses can be set clicking:

1. Set values

2. Store

3. Restart

Client (always)

ALC58

RoutingRouting

ALC59

RoutingRoutingALC Port and Address

ALC60

RoutingRoutingALC Port and Address in daisy chain

ALC61

Routing tableRouting table

Type and address

of crossed port

Type and address of crossed port towards

Destination

Netmask and IP address of Destination

Default destination

ALC62

Stored Routing TableStored Routing TableThe “Stored Routing Table” adds routing lines, after a

Restart, to the running Routing Table of the NE.In this way we can change Ports addresses (operation that

needs a restart) without loosing a remote NE:1. In “Stored Routing Table” add the routing lines

relevant to new port addresses you are going to set2. Set the new port addresses (…the equipment restarts)3. After the restart the equipment has new addresses and

the routing table configured already: the NE management is still running

ALC63

Station managementStation managementNEs connected to SCT can be assigned in

various stations using the tool :“Subnetwork Configuration Wizard”

ALC64

Alarm correlation Alarm correlation Every alarm is reported withAlarm beginning Alarm end (gravity info is maintained)

ALC65

Alarm acknowledgementAlarm acknowledgement

Alarm acknowledge is available inalarm history list: every acknowledgement can be managed completely in station list: new alarm info is highlighted by an asterisk

ALC66

Command loggerCommand loggerCmd Logger reads the list of operations, executed by the users,

stored on the controller of the equipment.The “log”, uploaded from equipment, is stored on the PC for

further consultations. Following filters are available: Operations date User address User type Operation name

ALC67

Configuration upload/downloadConfiguration upload/downloadUpload (from equipment)From Tool menu, open the proper TemplateSelect Upload operation and the equipment you want to upload information fromSave them in a file (*.cfg)

Download (to equipment)From Tool menu, open the proper file (*.cfg)Select Download operation and the equipment you want to download information to

Uploaded parameters and *.cfg file are editable using

Equipment Configuration Wizard.

ALC68

Configuration TemplateConfiguration TemplateConfiguration template: it is relevant to equipment radio parameters as frequency, attenuation, capacity, thresholds,…

Address configuration template: it is relevant to management parameters as port IP addresses, routing tables, remote elements tables, OSPF.

Both configurations are necessary during first installation or when Controller module is substituted with a spare one: you can use a file to download or set every parameter manually.

ALC69

Full backupFull backup

The whole amount of parameters (equipment parameters, address parameters and remote element table) can be uploaded from equipment, saved in a file (*.bku), downloaded to equipment.

These parameters cannot be editated.

ALC70

LCTLCTfor for ALALCC

ALC71

Configuration

BitrateModulation

Link ID (local only)

GeneralGeneral

ALC72

1) General preset:thresholds

HBer,LBer, EWL thresholds

Rx Power Low thresholds

ALC73

2) General preset:Rx switches

1+1

1+0

In case of Hber, Lber, EWL, first CRC correction

In case of no Rx

ALC74

Main parameters of the link are:

Configuration

Capacity

Modulation

Link ID

Frequency

Radio link parametersRadio link parameters

For local terminal

Setting has to be copied in remote terminal

Frequency

Capacity

Modulation

Link ID

Only “Configuration” has to be set locally (on local and after on remote)

For both local and remote terminal

ALC75

PRBS (Pseudo Random Bit Sequence)Alarm on “Checked signal” lineMeasure results and duration

Tributary selection if checked is Signal 2MBit

P.R.B.S replaces the traffic on selected channelP.R.B.S. test is pointed out as Manual Operation (subject to timeout)

Checked signal selection

Measure status

Pattern type

Sync Los events during test

ALC76

ATPC ATPC (Automatic Tx Power Control)(Automatic Tx Power Control)

ALC77

ATPC CharacteristicsATPC Characteristics

Maximum ATPC range: This range is limited by the amount of fixed attenuation with respect to the nominal TX power

Power Control Criteria: Remote terminal Received Signal Level (RSL) and BER

ATPC speed: 30 dB/s

Purpouse: To counteract the effect of flat fading, minimizing nodal interferences

ALC78

MaintenanceMaintenance

1. Reriodical Check2. Alarm Meaning3. Root Cause of Failure4. Troubleshooting 5. Loop Facilities

ALC79

Periodical Checks are used to check for radio equipment operation without the presence of any alarm conditions

Periodical Check

Check of the TX Power

Check of the Receive Signal Strength

( Reading Value must be match with link hop Cal.)

Check of BER and HOP performance

ALC80

Normal operating conditionNormal operating condition

Rx level on both ODU match values given by hop calculation.

Rx level accuracy: -40 dBm -75 dBm range ± 3dB -30 dBm -40 dBm range ± 4dB

ALC81

Faulty condition: alarm notificationFaulty condition: alarm notificationA faulty condition is pointed out byIDU front panel LEDs:

- AL: alarms, internal or external- TEST: manual operation active

SCT window:- Log history area (with alarm correlation)- Equipment view current alarms (with alarms grouping)

ALC82

ALARMSThere are two directions of alarms: Tx and Rx

Tx – This line starts in LIM and arrives to output flange: when a situation of more alarms is occurring, the most significative alarm of them is at the beginning of Tx chain, all the others after are due to this

Rx – This line starts in output flange and arrives to LIM: when a situation of more alarms is occurring, the most significative alarm of them is at the beginning of Rx chain, all the others after should be caused by this

Most Significant alarmRx

Tx

RIM

LIM

ODU

LIM

RIM

ODU

ALC83

COMMON group

Alarms not related to a specific part of the equipment but relevant to the link.

Example:.

– EOC radio alarm (relevant SCT management)– Link telemetry fail (relevant traffic, ATPC info, man op)

If both alarms are ON, the link is interrupted. Investigation must be made on a possible condition of bad

propagation, or equipment failure

ALC84

ALC85

No link between Local and Remote station. Traffic is cut.

Link telemetry is inserted in main radio frame in Bit Insertion circuit inside LIM, and contains commands for the remote station: switch off the radios on remote side in case of local RF loop, Link ID, ATPC info.

Telemetry link is a connection between local and remote IDUs.

TEST - if this alarm occurs, a double IDU loop (both branches) can be done: if this alarm disappears, local IDU is OK and the problem is after (propagation, local radios, remote equipment).

Link telemetry fail

ALC86

Communication Radio EOC Data link

No link between Local and Remote station or wrong port address configuration.

EOC is the channel involved in management communication.

If EOC radio link is active:

- Traffic is OK

- Management is cut (no remote)

ALC87

PRBS FailWhen PRBS is working and no signal is received on checked signal, in PRBS window the field Sync Los Alarm is active together with PRBS Fail in Current alarms window

Every ON-OFF transitionincreases the field

PRBS Fail Alarm Counter

ALC88

Communication 2Mb EOC Data link

No EOC channel is present on selected tributary in selected timeslot : wrong port address configuration or no tributary input (LOS). EOC is the channel involved in management communication.

If EOC 2Mb link is active:-Management is cut (no remote)- If relative LOS is active, traffic on that tributary is cut

ALC89

Revertive

When a branch is declared preferential, the switch on opposite branch gives Revertive alarm.

The return to preferential branch, when available again, happens after “Wait Time” period.

ALC90

2Mb/s G.704 (Trib.x) Radio Fail/AIS and/or Line Fail/AISWhen management messages come via tributary timeslot, further checks are performed on both directions of this tributary

ALC91

Tx FailTx Fail

When on remote side both radios don’t receive, on local side a Tx switch command is performed and Tx fail alarm is enabled.

When this alarm is on,check local ODU in stand by

This functionality is enabledin LCT – General PresetThe alarm remains activeuntil Reset is given

ALC92

Link IDLink IDAlarm is on if Link ID check is enabled (Link ID 0) and remote Link ID is different from the local one.

Traffic is cut but signal is received and measured. Output = AIS

This alarm causes:

ALC93

LIM groupLIM group

These alarms come fromExternal fault: tributary LOSLIM failure: -Multiplexer/demultiplexer failure -Modulator/demodulator failure Warning: modulator/demodulator

circuitry is spread into LIM and RIM modules.

RIM or ODU alarms propagation (seen in LIM as Baseband RX alarm)

ALC94

ALC95

Tributary-1 Signal loss

Loss Of Signal alarm is active when a situation opposite to that foreseen by configuration is performed on tributary interface:

No input oror

cable disconnected

Tributary connected

TRIB. STATUS

Tx

ALC96

Multiplexer fail

The alarm is given during multiplexing of input tributaries by

Overflow stuffing memories

Overflow is due to bad clock of one tributary (too fast: >+50ppm) or hardware failure

In case of Multiplexer Fail the signal forwarded to the radio is N x AIS (from all the N tributaries)

Tx

ALC97

Branch-x Modulator Fail

This alarm is active when at cable interface Tx IF modulated signal (330 MHz) is missing or is under a certain value; this is due to: Modulator faulty

Cable IDU-ODU open (that produces high VSWR value)

Traffic is cut

Tx

ALC98

Branch-x ODU-IDU Communication fail

This alarm occurs when on carrier used to receive information from ODU, or remote commands from other side, are detected:

CRC errors

Loss of frame

This carrier is separated from carrier used for opposite direction (IDUODU) and from TX or RX carriers

ALC99

Branch-x Demodulator Fail

Traffic is cut

This alarm is active when average deviation of symbol recognition is higher of a certain level.

Every problem in constellation gives Demodulator alarm: Problem of digital conversion of received signal from RIM I or Q signal missing High level of interference (bad quality but good Rx level) No Rx IF modulated signal (140 MHz) from ODU (no Rx, ODU faulty, IDU/ODU cable open)

Demodulator alarm causes:

Rx quality alarms (HBER, LBER, EWL) Rx signal alarms (BaseBand Rx)

Rx

Branch Rx quality alarm (software settable)

ALC100

Branch-x BaseBand RxThis alarm is active when

Bit Extraction does not work (in LIM)

Demodulator does not work (in LIM)

Demodulator does not receive from RIM or ODU

BaseBand Rx causes:

Demultiplexer Fail

Traffic is cut

Rx

ALC101

Demultiplexer Fail

The alarm is given during demultiplexing by:

Frame Alignment Word not recognised (LOF - loss of frame)

Overflow destuffing memories

Overflow memories of hitless Rx switch

BaseBand Rx alarm

In case of Demultiplexer Fail, output is AIS (from all the tributaries)

Rx

ALC102

RIM group

These alarms come from External fault: demodulator fail alarm and

ODU alarm are generated when ODU becomes faulty

RIM failure: PSU alarm with cable open/short alarm or modulator/demodulator alarms are active

Warning: modulator/demodulator circuitry is spread into LIM and RIM modules.

ALC103

ALC104

Branch-1 Power SupplyThis alarm is active when the PSU (Power Supply Unit) of one

RIM is switched off or is in failure condition

If the PSU is off, all the alarms of that RIM are activated:this alarm causes allRx Branch-1 alarms except those relevantRadio1 (is OFF)

Analysis order is:

PSUAll alarmedfrom now on

RT

IDU

ALC105

Branch-1 Cable open/shortThis alarm is active when the following situations occur:- Cable open alarm no current through cable interface: ODU is not supplied… so situation looks like PSU alarm (Rx alarms) with cable alarm instead PSU alarm- Cable short alarm overcurrent/low voltage through cable interface

Caused by high VSWRvalue of damaged cable

Cable opensituation

If both alarms are active, 48 V source has no enough current

ALC106

RT group

These alarms come fromExternal fault: Rx power low alarm is

generated because of bad propagation or by remote terminal faulty

ODU failure: PSU fail alarm or RF VCO alarm or RF IF alarm is activated

ALC107

ALC108

Branch-x IDU-ODU Communication fail

This alarm occurs in ODU when on carrier used to receive command from IDU, are detected:

CRC errors

Loss of frame

This carrier is separated from carrier used for opposite direction (ODUIDU) and from TX or RX carriers

ALC109

Branch-1 RT Radio Power Supply

This alarm is active when the Power Supply section of the radio doesn’t work properly or is in failure condition (voltage in input out of range).

Depending voltage value, radio can work.

When the under/over voltage is too high, radio is off and other alarms (cable open) cover this.

ALC110

Branch 1 RT VCO fail

This alarm occurs when VCO in RF unit is not able to lock any frequencies.

Every problem in VCO causes alarms in both directions: RF unit is not able to convert IF Tx in RF Tx (Tx Power Low alarm) and RF Rx in IF Rx .

In this situation the alarm is active together with Tx Power Low and all Rx alarms because RF channel is not locked.

Tx & Rx

ALC111

Branch 1 RT If fail

This alarm occurs when is not present IF signal inside ODU. There are two different IF signals but one alarm only.

No IF Tx : the alarm is on and causes Tx Power Low

No IF Rx: the alarm is on with all Rx alarms

Rt If fail can be caused by Modulator fail (no IF Tx)

When VCO is faulty, RF unit gives a IFRX signal made up of noise: this is enough to mantain IF fail alarm off (but Demodulator cannot work Rx alarms).

ALC112

Branch 1 RT Tx Power LowThis alarm occurs when Tx power is 3 dB under standard output of ODU-RF unit.

ATPC and manual attenuation do not affect this alarm that is due by internal failure of RF unit.

This alarm can be activated by a manual operation also: Tx Transmitter off in Radio Branch - Settings

If both Rx Power Low and Tx Power Low are active, RF unit inside ODU is faulty

Tx

ALC113

Branch 1 RT Rx Power LowThis alarm occurs when Rx power is under a defined threshold (about 10 dB under standard Rx level)

Threshold value can be set for both branches in range - 40 dBm- 99 dBm in LCT - General preset

The alarm Rx Power Low is a branch alarm and it is used to drive Rx switch

Rx

ALC114

UNIT group

This group generates alarms when one of the units, the equipment consists of, is faulty or does not respond to controller polling:

Unit failUnit is not respondingUnit is missingUnit hardware mismatchUnit software mismatch

ALC115

ALC116

OTHERALARMS

ALC117

Performance alarmsEvery performance measure can drive the relevant alarm if threshold is exceeded.

Threshold in sec. relevant 15 minutes alarm

Threshold in sec. relevant 24 hours alarm

Threshold in dB of Rx alarm

alarm counter reset

15 minutes alarms severity

If 0, alarm is disabled

ALC118

Performance monitoring

15 min.

alarms

24 hours

alarms

P RX > -5

5 dBmPRX < -70 dBm

R = 15 minutes

ALC119

Recorder : Prx

date time dBm

LCT

ALC120

Measures“Performances” is a group of measures, 15 minutes by 15 minutes, day by day, recorded by the equipment itself and downloaded on the PC (the download needs bitrate).

These measures remain active also with SCT (and PC) disconnected.

“Recorder Prx “ is the recording of Rx power on a log file inside the PC: every time a new value is measured a new “record” is written inside the log file with info of when (day, hour, minutes and seconds) and how much (dBm measured).

This recording remains active until SCT is connected to the equipment.

ALC121

Current AlarmsCurrent Alarms

ALC122

Switch modesSwitch modes Auto Preferential: operator can select which branch must be

operative without alarms. Wait Time = time before coming back to the preferential

branch when alarms disappear. In this way the controller doesn’t switch continuously in case of fleeting alarms.

Reset = Wait Time is not respected Full auto: both branches have same priority

Manual forcing Operator can select which branch must be operative

despite alarms

ALC123

Tx switch criteriaTx switch criteria1. RIM PSU alarm2. Manual forcing3. Cable short/ Cable open alarm Modulator failure ODU unit failure alarm VCO failure alarm IF unit alarm

ODU PSU alarm Tx power low alarm4. Rx failure on both remote radios 5. Revertive Tx

Highest priority

lowest priority

ALC124

Rx switch criteriaRx switch criteria1. RIM PSU alarm2. Manual forcing3. Cable short/open alarm

Base band unit failure alarm Demodulator failure ODU unit failure alarm VCO failure alarm IF unit alarm

ODU PSU alarm High BER alarm (selectable: BER>10-3,-4,-5)4. Low BER alarm (selectable: BER >10-6,-7,-8) 5. Early warning alarm (selectable: BER >10-9,-10,-11,-12) 6. RF input low (selectable from -40dBm to -99dBm)7. CRC pulse8. Revertive Rx

Highest priority

lowest priority

ALC125

EQUIPMENT FEATURE MANAGEMENT

ALC126

LOOP FACILITIES

Local Tributary Loop : used to test the cable interfacing

for the equipment upstream

Remote Tributary Loop : used to test two direction link

performance making use of an unused 2 Mbit/s signal

Baseband Loop : it permit to test the LIM circuits

IDU Loop : it permit to test the complete IDU (optional)

RF Loop : it permit to test the complete radio terminal

ALC127

MU

X-D

EM

UX

RF

E1 LOOP

BASEBAND LOOP

IDU LOOP

RF LOOP

LIM

RIM 1 ODU 1

AL : available loops data direction: - towards the equipment that has enabled the loop (baseband, IDU, RF) - selectable for E1 loop - only local loops

MOD- DEMOD

LOOPSLOOPS

MUX-DEMUX

RF

E1 LOOP

BASEBAND LOOP

IDU LOOP RF LOOP

LIM

RIM 1 ODU 1

AL : available loops data direction: - towards the equipment that has enabled the loop (baseband, IDU, RF) - selectable for E1 loop - only local loops

MOD- DEMOD

Line side

Radio side

Branch 1

BASEBAND LOOP

ALC128

ALC loop:ALC loop:external PRBSexternal PRBS

E1 loop line side : loop works with line enabled or not

E1 loop radio side : loop works with line enabled on local side and on remote side

Base Band, IDU, RF loop : loop works if line used is enabled local side and on remote side

Line side Radio side

ALC129

looploopss::internal PRBSinternal PRBS

E1 loop line side: it is before PRBS checking pointE1 loop radio side: loop works with line enabled on

remote side, indifferent* on local side.Base Band, IDU, RF loop: loop works any status of

local* and remote line__________________________________________________________ * PRBS enables automatically the local side of used line

Alarm OFF: signal is back!

ALC130

Propagation LinkPropagation Link

fLLogdBAfs 2044.92Free space loss (L in Km, f in GHz)

Received power dBGdBGdBAdBmPdBmP RTfsTR

LPT PR

h

E.I.R.P = Pt + Gt+ Cable loss

ALC131

AntennaAntenna

2

22

10D

LogGAntenna gain

D

D = antenna diameter

= wave lenght = c/f

= Aeff / Ageo= antenna efficiency 0,6

c = speed of light = 18103 ms

ALC132

1) Refraction1) Refraction

k < 4/3 (sub-standard)

k = 4/3 (standard)k > 4/3 (super-standard)

Snell law: 2211 sennsenn 1

2

n1

n2

n1

n2

n3

n4

ALC133

2) h2) hgeogeo …earth is not flat…earth is not flat

hgeo

R0 = 6378 km

L

0

2

R

Lhgeo

0

2

Rk

Lhgeo

with k<4/3 , k=4/3 , k>4/3 considering the troposphere refraction (previous page)

considering geometrical visibility on a planet with no air

ALC134

3) First Fresnel zone3) First Fresnel zone

RM

2

LRM

L

A nth fresnel zone gives in phase contributes to radio waves propagation.

In order to avoid attenuation is important that first fresnel zone is without obstacle: to tower height calculation, must be add the ray of biggest Fresnel zone, the first zone

ALC135

Height of the towersHeight of the towersWe have to consider:

earth’s curvature

k effect (refraction)

first Fresnel zone free

From the first we obtain hgeo , with refraction hgeo becomes

and from the last we have to add also RM

geoh

20

2 L

Rk

LRhh Mgeotower

ALC136

exampleexampleL = 20 km

f = 23 GHz

k = 4/3

R0= 6378 km

mkmR

Lhgeo 47047.0

333.1 0

2

+

mL

RM 1.82

htower= 47m + 8.1m = 55.1m

ALC137

Fade MarginFade Margin…from previous page: 4QAM/16x2

L = 20 km PT= +20 dBm

f = 23 GHz HBER - 82 dBm

dBfLLogdBAfs 7.14526.5344.922044.92)(

x = gain of antennas

dBGdBGdBAdBmPdBmP RTfsTR

FM= PR-HBER PR= -82dBm + 40dB = -42dBm

FM = 40dB (purpouse)

GT+GR= 2G = PR-PT+Afs= -42dBm-20dBm+146dB=84dB

GT=GR=42dB D=60cm G=40dB D=80cm G= 42,6dB

ALC138

Rain attenuation (f > 8GHz )Rain attenuation (f > 8GHz )

freq \ rain 25 mm/h 100 mm/h

10 GHz 0.5 dB/km 2.5 dB/km

15 GHz 1.5 dB/km 7 dB/km

20 GHz 2.1 dB/km 10 dB/km

30 GHz 4 dB/km 15 dB/km

40 GHz 6 dB/km 20 dB/km

ALC139

Rain depolarizationRain depolarization

Wind

Drag (air resistence)

Drop weight

E

Hvertical polar. e.m. wave

E

H

horizontal polar. e.m. wave

I

GHz

hv

ALC140

MultipathMultipath

Indirect ray, depending on its phase, can increase or decrease the power of the main stream

Two rays model )(1 jebH

Direct ray: amplitude = Indirect ray: amplitude = b , phase delay = , time delay =

Direct ray

Indirect ray

A B

In B position, received signal has a notch every 1/ Hz with deepness depending on b

ALC141

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