PCR Paperless Chart Recorder & IRU600 EHP. Hassan Dakroub Solutions Architect

Transcription

1 PCR Paperless Chart Recorder & IRU600 EHP Hassan Dakroub Solutions Architect

2 WAVE PROPAGATION Microwave link propagation is influenced by REFRACTION, REFLECTION, and DIFFRACTION radiowave propagation. GEO, MEO, and LEO Satellites GEO: Geo-synchronous Earth Orbit MEO: Medium Earth Orbit LEO: Low Earth Orbit Ionosphere Sky Wave (MF, HF only) Troposphere Transmitting Antenna REFRACTED WAVE NON-REFRACTED (k=1) WAVE MULTIPATH RAYS Receiving Antenna Ground Wave True Earth s Curvature (LF/MF only)

3 TRATING k-factor FADING (1) k = 2/3rds UPWARD (INVERSE) BENDING, OFTEN WITH COLD FRONT MIGRATION OVER WARM MOIST TERRAIN, OBSTRUCTION FADE k = 1 STRAIGHT LINE OVER CURVED EARTH; DRY HIGH ELEVATION CLIMATE Ray bending is shown greatly exaggerated DUCTING STANDARD k = 4/3rds SLIGHT DOWNWARD REFRACTION; INLAND, TEMPERATE CLIMATE k = 3 SIGNIFICANT DOWNWARD REFRACTION; COASTAL, HUMID CLIMATE k = PARALLELS EARTH S CURVATURE; HEAVY DOWNWARD REFRACTION; COASTAL, VERY HUMID CLIMATE 8 k = -1 DOWNWARD BENDING TO EARTH; SEVERE DOWNWARD REFRACTION, DUCT ENTRAPMENT, BLACKOUT FADE TRUE EARTH S CURVATURE ( k = 1)

4 G TYPES, MULTIPATH Fading Type Typical AGC Recording Stable Atmospheric Multipath fading occurs when only a small number of secondary reflected or refracted paths are received simultaneously with the desired path. Fading characteristic is slow, but occasionally fast and deep fades occur. Turbulent Atmospheric Multipath causes fast but low magnitude fades with fewer outages. Remedy: Increased fade margin, reduces outage times. For each 10dB, outage is dropped by factor of 10. Multipath is highly selective, diversity ( space, frequency, hybrid) reduce outage by factor of 100 or more. Antenna orientation, and size for better selectivity against slightly off-path multipath rays. AVIAT NETWORKS AVIAT

5 FADING TYPES, REFLECTIONS FROM GROUND OR WATER Fading Type Typical AGC Recording A stable signal reflected from an exposed reflection point may add to the desired signal to: Increase the composite RF level by as much as 6 db. Completely cancel the signal, causing a 50 db or greater fade. A path hung-up on a stable reflection may remain depressed for days and weeks. Remedy: Fade margin can help. Non-Sapce Diversity paths could be shielded from the reflected signal by trees and screens. Any amount of space diversity spacing can eliminate outages from this type of fades. Antennas are tilted upwards, to increase discrimination to the reflected ray. AVIAT NETWORKS AVIAT

6 DE-CORRELATED REFLECTIONS (PATHLOSS RESULT) AVIAT NETWORKS AVIAT

7 FADING TYPES, RAINFALL Fading Type Typical AGC Recording This type of fade generally causes outages only above 10 GHz. Rain outage for lower for lower frequencies is very rare. Outages are caused by outages of the path. Thunderstorms average 5 miles in diameter, and 5-15 minutes in duration. Fades are non-selective, causing outages in both directions. Vertical polarization is less susceptible to rainfall attenuation, compared to horizontal Pol. Outages per year are directly proportional to path distance. Remedy: Increase Fade margin. Use Vertical polarization. Route diversity AVIAT NETWORKS AVIAT

8 11 GHZ AND 18 GHZ RAIN FADE EXAMPLE WASHINGTON, DC An increase in fade margin reduces the numbers of rain outage events and their durations only minimally* GHz Attenuation, db min rain outage (33 db fade margin) 18 GHz Time, Minutes *Frequency Band, Polarization, and Path Length have much greater impact on Rain Outage than fade margin

9 FADING TYPES, INVERSE BENDING AND ATTENUATION Fading Type Typical AGC Recording Cool Valleys, or Fog over Cold water, causes inverse bending for the signal, resulting in a diffraction loss. Non-selective and affects both directions simultaneously. Remedy: Increase antenna height and fade margin are the primary solutions.

10 ABL (GROUND-BASED) DUCT FADE ANATOMY View this slide in.pps(its presentation mode) to see animation (fade sequence) Reflection, Obstruction, and Duct Entrapment (Blackout) Fades Normal Propagation +10dB 0dB -10dB -20dB ABL Atmospheric Boundary Layer -30dB -40dB 21:00 22:00 23:00 24:00 1:00 2:00 3:00 4:00 5:00 6:00 7:00

11 FADING TYPES, BLACKOUT Fading Type Typical AGC Recording Low clearance paths traversing areas supporting super refractive ground-based layers have experienced complete loss of signal for up to 24 hours. A rising atmospheric layer may intercept and trap the path. The failure is occasionally preceded by reflection fades, and an obstruction layer. Remedy: Design path over a 150 duct layer and K=1, with space diversity. Deploy with a high-low configuration. Widely spaced diversity antennas may help. AVIAT NETWORKS AVIAT

12 PCR Paperless Chart Recorder Overview Information extracted from Aviat Networks radios is presented in a single-screen graphical format, enabling the analyst to quickly assign for appropriate and timely remedial actions a path performance issue to a radio module, antenna feeder system component, external RF or EMI interference, or to a geoclimatic issue. PCR can reveal multipath and power fading types, ducting layer entrapment, defocusing, and signal dispersion (distortion) events, inappropriate diversity spacings, antenna misalignments, movements, and k-factor decouplings, interferences, site noise, maintenance activity, and module behavior.

13 PCR Data Collection Target performance data, status, and analog traces include: Continuous second-by-second main/diversity receive signal level (RSL) tracks; also power output, SNR, and ODU temperature ( 0 C) traces in Eclipse and ODU 600 radios Individual main/diversity receiver error performance alarms as well as transmitter and receiver module status alarms Early warning (anticipatory) signal degradation, amplitude slope, and data eye quality alarms for some radios Transmitter and receiver 1+1 on-line status (but not fast Eclipse and ODU 600 frame-by-frame errorless data switches) Traffic alarms such as ES (errored seconds) and SES/LOF outages (loss of frame or packets) Exacting local and GMT dates and times

14 PCR Data Extraction from Portal for Eclipse and ODU 600 Radios Aviat Networks Portal Diagnostics/History screen provides radio A/B RSL traces and performance alarms over a 7 day period. Extracting long-term PCR data from this Portal screen to a file folder is but a single click away. Export PCR data tab

15 The PCR History Data Viewer All Data Screen AVIAT

16 The PCR History Data Viewer Visible Menu Screen Up to 4 Analog traces, and up to 32 alarms can be selected to be shown. Analog traces and alarms differ between platforms.

17 The PCR History Data Viewer Screen - Expanded This PCR screen can then be expanded from All Data with a right mouse click to any lesser 1-, 2-, or 3-month, week, 1- or 2-day, 1-, 3-, or 12-hour, or 1- or 15- minute period on a single screen display with its user-selected A/B alarms and analog tracks (receiver RSLs, transmitter powers, SNR tracks, and ODU temperatures) for a more detailed examination, as seen in its 3 hr screen below.

18 THE PCR HISTORY DATA VIEWER SCREEN EXAMPLE 2 The PCR screen below is a one week display showing RxA1/A2 main/diversity receiver alarms and errorless data switching, and DS1 traffic performance in one direction of an active 10.5 GHz space diversity overwater hop exhibiting noncorrelative fades and thus no tributary error degradation or SES outages.

19 THE PCR HISTORY DATA VIEWER SCREEN EXAMPLE 3 PCR screen prints can be pasted into Excel or PowerPoint to add annotations for a report, as seen below. The error performance of this Eclipse IRU 600 hop with excessive clearance is highly degraded by an exposed long-delayed specular reflection causing 20 db early dispersive (spectrum distorting) fade outages. With inadequate antenna discrimination, this hop s path clearance was lowered 50 ft.

20 THE PCR HISTORY DATA VIEWER SCREEN EXAMPLE 4 PCR can easily identify antenna movements and instabilities from snow and ice loads and wind gusts - load release and wind gust jerks - as is clearly seen in the PCR data extracted from a 10.5 GHz Eclipse IRU 600 hop deployed in New England. Local weather station records for those days of interest are pasted into the screen. Dual and quadruple PCR screens with synchronized dates and times, as seen in the following slides, are essential to the evaluation of hop performances.

21 POWER FADING AND REFRACTIVE MULTIPATH CAUSED BY ABL DUCT ENTRAPMENTS PCR screen shows the main and diversity signals entrapped in severe ABL (atmospheric boundary layer) surface ducts causing fast refractive multipath fade outages. This power fade lowered the receive signal levels (fade margins) in both the main and diversity receivers some 20 db over this 1hr period, resulting in fast, frantic refractive multipath fades to below the receivers -70 dbm outage thresholds that caused two OC-3 tributary outage events.

22 POWER FADING CAUSED BY SIGNAL DEFOCUSING (BLACKOUT) FADES PCR History Data Viewer identifies beam-defocusing fades in a diversity or non-diversity hop that divert or spread the RF wave front from the receive antennas by their sudden, deep losses of signal that affect the main and diversity paths equally Fortunately, defocusing fades that cause catastrophictraffic outages are rare, most often occur in flatland hops deployed in difficult geoclimateregions, and usually of short (5-15 minute) duration, although this Gulf of Mexico blackout fade lasted 2 hours.

23 POWER FADING CAUSED BY ANTENNA MISALIGNMENT (DECOUPLING OR TOWER INSTABILITY) The above PCR Screen shows both directions of a long 7.5 GHz path whose performance in one direction is heavily impacted by the slow twisting of the top of a tower at one site (Zaragoza, lower screen). The 12ft (3.7m) main )transmit) antenna at its top is twisted slowly off-path over 2 degrees, causing far-end 40+ db A1/A2 main/diversity receiver RSL losses and STM-1 tributary outages at Gonzalez (upper PCR screen), but excellent error performance - only A1 (main) receiver, not STM-1, outages - at Zaragoza (lower screen). The lower PCR screen above shows the more stable A2 diversity antenna lower on Zaragoza s tower twisted only slightly off-path (red trace), so its RSL was still high thus no STM-1 outages occurred in that direction.

24 POWER FADING CAUSED BY RAPID ANTENNA MOVEMENTS Two-way PCR exhibits abrupt db main and diversity receiver RSL changes exactly correlative in both directions of a hop, due to one of the two towers taking a 1-2 degree offset with wind gusts. or temperature changes. In cold climates, water in a waveguide freezing at night (high RSL) and thawing at noon (low RSL) has caused similar RSL fluctuations.

25 OUTAGES CAUSED BY ATPC DEBOOSTS (TIMEOUTS) DURING POWER (DUCT, RAIN) FADING Two-way PCR exhibits abrupt db main and diversity receiver RSL changes exactly correlative in both directions of a hop, due to one of the two towers taking a 1-2 degree offset with wind gusts. or temperature changes. In cold climates, water in a waveguide freezing at night (high RSL) and thawing at noon (low RSL) has caused similar RSL fluctuations.

26 POWER FADING DUE TO RAIN CELL PASSAGE IN MILLIMETERWAVE (11-38 GHZ) AND OTHER HOPS Rain fades in microwave hops are clearly identified by the classic V shape, absence of multipath fading, and 5-20 minutes duration. Radome Wetting increase the duration of rain fades. H polarization fades are typically 6 db deeper than V-Polarization. AVIAT

27 POWER FADING DUE TO RAIN CELL PASSAGE IN MILLIMETERWAVE (11-38 GHZ) AND OTHER HOPS (CNTD) Rain events can be correlated with weather website resources, that can show wind/rain/humidity data for regions.

28 SPECTRUM DISTORTION (DISPERSIVE FADING) THAT CAUSE INCREASED OUTAGE TIME Dispersive fading - RF signal distortion due to high-level path reflections that trigger RCS (reverse channel switch) commands in 1+1 equipment configurations - cause highly degraded performance (Sync Loss/LOF outages) in both directions of a Constellation 155/180 overwater hop seen in PCR Screen below. The path has wide-beamwidth 6ft (1.8m) dishes with inadequate discrimination to long-delayed specular reflections that caused dispersive fades. The high numbers of OC-3 tributary outages (Sync Loss/LOF alarms) seen in PCR Screen were reduced more than 99% with the uptilt of the low-end s wide-beamwidth 6ft (1.8m) main and diversity antennas that provided adequate discrimination to a low-delayed high-level specular reflection. Another more costly option would have been to replace these dishes with larger narrower beamwidth antennas, but with its now-excellent performance that is considered unnecessary.

29 SPECTRUM DISTORTION AND OUTAGES CAUSED BY LARGE AIRCRAFT CROSSING THE PATH PCR Screen below shows a multitude of DS1 tributary outages and radio alarms with only 5-10 db dispersive fades in both directions of a non-protected, non-diversity Constellation 11 GHz path over a 1-week period. No other Constellation path in the system was affected, and proper radio performance was verified on this hop. This 1-week expanded PCR screen disclosed that RSL jumps and occasional outages occurring at 7AM-11PM each day coincided exactly with commercial airplane arrivals and departures intercepting this cross-runway microwave path. Antenna repositioning at the airport terminal correct this Constellation hop s severely degraded performance.

30 SE EVENT LOG AND PCR SCREEN SHOWING A 3 SEC DURATION FADE TRAFFIC OUTA 22AM ON 27JUN13, IRU 600 ACM HOP AVIAT

31 AVIAT IRU EHP BREAKTHROUGH TRANSMIT POWER PERFORMANCE 31 March 2015 AVIAT

32 0 EXTRA HIGH POWER OPTION Optional internal module delivers industryshattering RF power output Available in L6, U6, 7 (FCC) and 11 GHz 39 dbm at RFU output, 37.5 dbm at antenna port (QPSK to 256QAM) No reduction/back-off in system gain for high capacity links Up to 8 db additional Tx power compared to IRU 600 High Power, and up to 11dB compared to SP Can be retrofitted to IRU 600 (v3) for L6/U6/7 GHz March 2015 AVIAT

33 IRU600 HP VS. EHP TX POWER (AT ACUANTENNA PORT) No power backoff for high modulations Flat Tx Power across all Modulations! 8 db max, 5.5 db average improvement L6/U6GHz guaranteed figures, at ACU antenna port. Typical values are 0.5 db better (EHP only) 1 or 2 db lower at 512/1024QAM under test 33 March 2015 AVIAT

34 TX POWER #1 FACTOR FOR LOWER TCO AVIAT IRU600 EHP COMPETITION $$ TCO $$$$ TCO 7.5 or 8 db = 2 antenna sizes = $30,000 lower TCO (over 5 years) March 2015 AVIAT

35 ER POWER ENABLES HIGHER CAPACITY 30 MHz CHANNEL 64QAM 256QAM DELTA EHP vs SP Throughput Mbit/s % Tx Power Output dbm +29 (SP) (EHP) +8.5 Rx Threshold (10-6 BER) dbm System Gain db % more capacity & higher Path reliability, without changing antennas March 2015 AVIAT

36 HINGS TO KNOW ABOUT IRU600V3 EHP (1 OF 2) Technological breakthrough Industry-leading Tx Power: 38.5dBm guaranteed / 39dBm typical at RFU Tx port. Up to 7.5/8dB more than v3 HP and up to 10.5/11dB more than v2 HP Smaller antennas, higher path reliability, longer hops, higher throughput,s Cutting edge new PA technology Highly efficient - delivering more Tx power for less power consumption: IRU600v3 EHP has modestly higher power consumption than IRU600v2 HP but delivers up to 11dBm extra Tx power! V3 Power consumption reduces when Tx power is attenuated, reducing energy cost & extending expected life Same Tx power from QPSK to 256QAM (1 or 2dB lower at 512/1024QAM) Getting maximum capacity at the Tx power of QPSK no back off needed!

37 TOP THINGS TO KNOW ABOUT IRU600V3 EHP (2 OF 2) More Tx Power while maintaining great threshold EHP supports same or similar Threshold as SP/HP Upgradable! Can buy SP & HP v3 RFU* initially, then upgraded to EHP later. Another way to future-proof your investment Compatible & Standardized EHP uses same form factor as SP/HP, can be mixed in a hop & in a chassis with SP & HP EHP can be mixed with v1 and v2 in a chassis and over the air Common parts & accessories simplifies sparing & reduces cost Ex: Uses same ACU/fan tray/extension kits/expansion kits/etc. as SP/HP EHP limits draw on INU by using a DC input (like v1/v2 HP) Can upgrade SP & HP RFUs to EHP without having to reduce INU loading to compensate

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