1
BASIC INTRODUCTION INTO MICROWAVE THEORY AND IP
APPLICATIONS
FUNDAMENTALS OF MICROWAVE RADIO
COMMUNICATION FOR IP AND TD...
Agenda
July 20132 AVIAT NETWORKS |
Introduction……………………………………..………….…….A
What is Microwave……….…………………….………….…….B
• Spectru...
A. INTRODUCTION
• The field of terrestrial microwave communications is constantly experiencing a steady
technological innovation to accomm...
B. WHAT IS TERRESTRIAL MICROWAVE?
6
Flushing ANSI
values
AVIAT NETWORKS |
Terrestrial Microwave?………..What is it?
A line-of-sight point-to-point wireless tec...
7 AVIAT NETWORKS |
Terrestrial Microwave?………..What is it? (cont'd)
July 2013
8 AVIAT NETWORKS |
Terrestrial Microwave?………..What is it? (cont'd)
July 2013
60% F1
60% F1
B.1 SPECTRUM
10 AVIAT NETWORKS |
Frequency Spectrum
July 2013
11 AVIAT NETWORKS |
Some Standard Frequency Bands for Terrestrial Microwave
Band Radio Frequency Recommendations
(MHz) FCC...
12 AVIAT NETWORKS |
RF Atmospheric Attenuation
July 2013
B.2 A TERRESTRIAL MICROWAVE LINK
AND APPLICATIONS
14 AVIAT NETWORKS
Data
Equipment
Outdoor RF/Antenna
Gigabit
Ethernet
NxDS1/E1
PABX
Equipment
Data
Equipment
Outdoor RF/Ant...
Radio Node Hardware Example - Eclipse
15 AVIAT NETWORKS | July 2013
16 AVIAT NETWORKS |
Cellular Site MSC-BSC-BTS IP/TDM Interconnectivity
MSC (MTSO) - Switching Office (POP)
BTS - Base Stat...
Mobile RAN and Backhaul Transport
July 201317 AVIAT NETWORKS |
IEEE, Oct. 2010
Carrier Ethernet MPLS-TP
Outdoor Networked Radio (4-QAM through 1024-QAM)
July 201318 AVIAT NETWORKS |
B.3 HOW FAR CAN TERRESTRIAL
MICROWAVE GO?
Typical Relative Path Lengths with Clear Line of Sight (LOS)
20 AVIAT NETWORKS |
Path Length, mi (km)
6/7/8 GHz
11 GHz
18 ...
21
Examples of Very Long IP Microwave Links for Air Traffic Control
July 2013
B.4 HOW MICROWAVE RADIOS
COMMUNICATE
July 201323 AVIAT NETWORKS |
Adaptive Coding and Modulation for IP Backhaul
Throughput
[Mbit/s @ 7 MHz Ch BW]
(QPSK) 10
(1...
July 201324 AVIAT NETWORKS |
Coding Gain in AWGN Channels
• Coding gain in AWGN (Additive White Gaussian Noise) channels i...
July 201325 AVIAT NETWORKS |
MLCM Signal Constellation
d
√2 d
1 0
Level 1
1 0
2d
1 0
Level 2
A set of 64 symbols is divide...
B.5 HOW REPEATERS EXTEND THE
RANGE
27 AVIAT NETWORKS |
Passive Reflector
"Billboard"
Site A
Single
Reflector
Site B
Terrain
Obstruction
Passive Repeater Arra...
28 AVIAT NETWORKS |
Site A Beam Bender
(Back-To-Back
Parabolics)
Terrain
Obstruction
Site B
Beam Bender
Back-To-Back Parab...
B.6 MICROWAVE TOWER ISSUES
Twist and Sway
30 AVIAT NETWORKS | July 2013
A B C
Antennas: HSX12-77 Antennas: HSX12-77
Beamwidth: ±0.35o Beamwidth: ±0.3...
B.7 CAUSES OF MICROWAVE
DISCONNECT PERIODS
Causes of Traffic Disconnect - Outage
32 AVIAT NETWORKS |
• Rain outage (predictable and therefore acceptable) in access l...
C. SOME EXAMPLES OF L2 RADIO
TECHNOLOGY
Eclipse Intelligent Node Unit
• The most compact nodal
solution on the market
• Single indoor unit
supporting multiple rad...
• Lower Losses than Couplers
• More ODUs per Antenna feed
• Fewer Antennas
• Increased system gain
• Reduces antenna sizes...
D. WHY PROPAGATION?
Radio Wave Propagation
37 AVIAT NETWORKS |
GEO, MEO,
and LEO
Satellites
Sky Wave
(MF, HF only)
REFRACTED WAVE
NON-REFRACTE...
Ray Tracing Along a Profile
July 201338 AVIAT NETWORKS |
• Not unlike outbound ripples from a pebble
tossed into a quiet p...
Carrier Ethernet Link Design Parameters
39
Flushing ANSI
values
AVIAT NETWORKS |
• NETWORK LAYOUT
• FIELD VERIFICATION
• M...
Multipath Propagation
40 AVIAT NETWORKS |
Excessive Path
Clearance
Elevated Super-refractive
Layer
Specular Reflection
Jul...
E. ANTENNAS AND FEEDER SYSTEMS
42 AVIAT NETWORKS |
Reflector Antennas
Photos courtesy of Andrew Corporation
July 2013
Standard parabolic
Standard parabol...
43 July 2013
44 AVIAT NETWORKS |
Antennas
• Used to efficiently radiate/receive the energy towards/from
the far-end of the link
• Impor...
45 AVIAT NETWORKS |
Antenna Alignment Issues
Antenna aligned on a side-lobe
Correct antenna alignment
July 2013
46 AVIAT NETWORKS |
Antenna Decoupling
• Angle of arrival may vary by as much as 1° on long paths
in humid areas at night;...
47 AVIAT NETWORKS |
PRESSURIZED (AIR)
COAXIAL CABLE
UNPRESSURIZED (FOAM)
COAXIAL CABLE
ELIPTICAL
WAVEGUIDE
RECTANGULAR (RI...
48 AVIAT NETWORKS |
Transmission Lines (Feeder Systems)
• Coaxial cable
• Air dielectric (lower loss)
• Foam dielectric (h...
F. RF PROTECTION
Definitions
50 AVIAT NETWORKS |
• Protection Schemes provide a level of security from long-
term (>10 CSES/event – Consecu...
F.1 MONITORED HOT STANDBY
1+1 Monitored Hot Standby Outdoor Node (cont’d)
July 201352 AVIAT NETWORKS |
Tribs 1-20
Protection
Cable
ODU 600sp/hp/ep
Y...
1+1 Monitored Hot Standby Outdoor Node
July 201353 AVIAT NETWORKS |
Equal split (3dB)
RF Splitter is also
possible with th...
H.2 MONITORED HOT STANDBY WITH
SPACE DIVERSITY
July 201355 AVIAT NETWORKS |
Space Diversity with Horizontal Offset
1+1 Monitored Hot Standby Space Diversity - Outdoor Node
July 201356 AVIAT NETWORKS |
Multipath forms essentially
in the v...
THANKS YOU AND SUGGESTIONS
Suggestions
58 AVIAT NETWORKS | July 2013
• Professional Affiliations News Websites
• IEEE
• LinkedIn www.bbc.com
www.foxn...
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FUNDAMENTALS OF MICROWAVE RADIO COMMUNICATION FOR IP AND TDM

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BASIC INTRODUCTION INTO MICROWAVE THEORY AND IP APPLICATIONS

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FUNDAMENTALS OF MICROWAVE RADIO COMMUNICATION FOR IP AND TDM

  1. 1. 1 BASIC INTRODUCTION INTO MICROWAVE THEORY AND IP APPLICATIONS FUNDAMENTALS OF MICROWAVE RADIO COMMUNICATION FOR IP AND TDM Presented by: Richard Laine / Ivan Zambrano Silicon Valley, CA.
  2. 2. Agenda July 20132 AVIAT NETWORKS | Introduction……………………………………..………….…….A What is Microwave……….…………………….………….…….B • Spectrum……………………………………………………………….…..B.1 • A Terrestrial Microwave Link and Applications...……………………....B.2 • How Far can Microwave Go………………………………………..........B.3 • How Microwave Radios Communicate……………………………….....B.4 • How Repeaters Extend the Range……………………………………....B.5 • Microwave Tower Issues………………………………………………….B.6 • Causes of Microwave Disconnect Periods……………………………...B.7 L2 Radio Technology………..………………………………......C Why Propagation…………………......…………..…………......D Antennas and Feeder Systems.…………………….………….E RF Protection……………………………………………………..F
  3. 3. A. INTRODUCTION
  4. 4. • The field of terrestrial microwave communications is constantly experiencing a steady technological innovation to accommodate the ever-demanding techniques telecom providers and private microwave users employ when deploying microwave radios in their cloud networks. • In the beginning of this wireless evolution, the ubiquitous DS1s/E1s and DS3s/E3s crisscrossed networks transporting mainly voice communications, data, and video. • With the advent of Carrier Ethernet and IP, new techniques had to be developed to ensure the new Layer 2 radios were up to par with the new wave of traffic requirements including wideband online-streamed media. These new techniques come in the form of Quality of Service (QoS), Traffic Prioritization, RF Protection and Design, Spectrum Utilization, and Capacity Enhancement. • With Carrier Ethernet and IP, network design becomes more demanding and complex in terms of RF, Traffic Engineering, and QoS. However, the propagation concepts remain unchanged from TDM link engineering while the link’s throughput of L2 radios doubles, triples, or quadruples employing enhanced DSP techniques. Introduction 4 AVIAT NETWORKS July 2013
  5. 5. B. WHAT IS TERRESTRIAL MICROWAVE?
  6. 6. 6 Flushing ANSI values AVIAT NETWORKS | Terrestrial Microwave?………..What is it? A line-of-sight point-to-point wireless technology for the transmission of Internet, voice, data, and online-streamed media. July 2013 Refracted Beam Direct Beam Reflected Beam
  7. 7. 7 AVIAT NETWORKS | Terrestrial Microwave?………..What is it? (cont'd) July 2013
  8. 8. 8 AVIAT NETWORKS | Terrestrial Microwave?………..What is it? (cont'd) July 2013 60% F1 60% F1
  9. 9. B.1 SPECTRUM
  10. 10. 10 AVIAT NETWORKS | Frequency Spectrum July 2013
  11. 11. 11 AVIAT NETWORKS | Some Standard Frequency Bands for Terrestrial Microwave Band Radio Frequency Recommendations (MHz) FCC, NTIA, and ITU-R) 4 GHz 3,600 – 4,200 FCC Part 101 and Rec F.635-6 (2006) U4 GHz 3,803.5 – 4,203.5 ITU-R Rec F.382-8 (2006) 5 GHz 4,400 – 5,000 ITU-R Rec F.1099-3 Annex-1 (2007) 5 GHz 4,400 – 4,990 U.S. Federal (NTIA) L6 GHz 5,925 – 6,175 FCC Part 101, Rec F.383-7 (2007) U6 GHz 6,525 – 6,875 FCC Part 101 U6 GHz 6,430 – 7,110 ITU-R Rec F.384-9 (2007) 7/8 GHz 7,125 – 8,500 U.S. Federal (NTIA) L7 GHz 7,125 – 7,425 ITU-R Rec F.385-8 Annex-1 (2007) U7 GHz 7,425 – 7,725 ITU-R Rec F.385-8 (2007) 7W GHz 7,110 – 7,750 ITU-R Rec F.385-8 (2007) L8 GHz 7,725 – 8,275 ITU-R Rec F.386-7 Annex-6 (2007) 10 GHz 10,550 – 11,680 FCC Part 101, Rec F.747 (1992) 11 GHz 10,700 – 11,700 FCC Part 101, Rec F.387-10 (2010) 13 GHz 12,750 – 13,250 ITU-R Rec F.497-6 (2007) July 2013
  12. 12. 12 AVIAT NETWORKS | RF Atmospheric Attenuation July 2013
  13. 13. B.2 A TERRESTRIAL MICROWAVE LINK AND APPLICATIONS
  14. 14. 14 AVIAT NETWORKS Data Equipment Outdoor RF/Antenna Gigabit Ethernet NxDS1/E1 PABX Equipment Data Equipment Outdoor RF/Antenna Gigabit Ethernet NxDS1/E1 PABX Equipment 6 to 360 Mbit/s QPSK to 256 QAM July 2013 One "hop" of Microwave
  15. 15. Radio Node Hardware Example - Eclipse 15 AVIAT NETWORKS | July 2013
  16. 16. 16 AVIAT NETWORKS | Cellular Site MSC-BSC-BTS IP/TDM Interconnectivity MSC (MTSO) - Switching Office (POP) BTS - Base Station BSC - Base Station Controller BSC 18/23 GHz (NxDS1/E1) 23/38 GHz (NxDS1/E1) 18 GHz (NxDS1/E1) 18 GHz (DS3/E3) Eclipse Eclipse BTS BSC Eclipse MSC (MTSO) Eclipse BTS BTS BTS Eclipse IRU 600 Self-Healing STM-1/OC-3/Ethernet /IP Ring Typical TDM Capacity Requirements OC-3/STM-1 to OC-12/STM-4 16xDS1/E1 to OC-3/STM-1 BSC to MSC 2-16xDS1/E11-2xDS1/E1BTS to BSC 3G2GHops BTS to BTS 1-2xDS1/E1 2-16xDS1/E1 July 2013
  17. 17. Mobile RAN and Backhaul Transport July 201317 AVIAT NETWORKS | IEEE, Oct. 2010 Carrier Ethernet MPLS-TP
  18. 18. Outdoor Networked Radio (4-QAM through 1024-QAM) July 201318 AVIAT NETWORKS |
  19. 19. B.3 HOW FAR CAN TERRESTRIAL MICROWAVE GO?
  20. 20. Typical Relative Path Lengths with Clear Line of Sight (LOS) 20 AVIAT NETWORKS | Path Length, mi (km) 6/7/8 GHz 11 GHz 18 GHz 23/38 GHz 100(160)5(8) 10(16) • Path lengths in the different RF bands are estimates only • A path analysis is required to calculate the reliability and availability criteria. Maximum EIRP (Effective Isotropic Radiated Power) = +55 dBW = +85 dBm 3(5) July 2013 80 GHz
  21. 21. 21 Examples of Very Long IP Microwave Links for Air Traffic Control July 2013
  22. 22. B.4 HOW MICROWAVE RADIOS COMMUNICATE
  23. 23. July 201323 AVIAT NETWORKS | Adaptive Coding and Modulation for IP Backhaul Throughput [Mbit/s @ 7 MHz Ch BW] (QPSK) 10 (16QAM) 20 (64QAM) 30 Example: 99.990% 99.995% 99.999% Rain Availability or Path Reliability Fade Margin: 24 dB (20%) 31 dB (55%) 40 dB (25%) Time Fast Multipath or Slow Rain Fade Best Effort Traffic Less Critical Traffic Critical Traffic (256QAM) 40
  24. 24. July 201324 AVIAT NETWORKS | Coding Gain in AWGN Channels • Coding gain in AWGN (Additive White Gaussian Noise) channels is defined as the amount that the bit energy or S/N power ratio can be reduced under the coding technique for a given Pb (bit error probability) or Pbl (block error probability) Shannon Limit: Threshold, Eb/N0, below which reliable communication can not be maintained! This ratio can be considered a metric that characterizes the performance of one system vs. another. The smaller the ratio, the more efficient is the modulation and detection process for a given Pb. Pb 10-2 10-4 10-6 Uncoded Coded -1.6 dB-8 dB 16 dB X dB of Coding Gain depending on modulation and BW Eb/N 0 mNoEbNC log10//  With concatenated coding, the coded curve is steeper than with Reed-Solomon alone. Example: The C/N of a p-t-p radio featuring 4DS1/16QAM and Eb/N0 = 11.9 dB @ 10-6 equals: 11.9 dB + 10 log4 = 17.9 dB
  25. 25. July 201325 AVIAT NETWORKS | MLCM Signal Constellation d √2 d 1 0 Level 1 1 0 2d 1 0 Level 2 A set of 64 symbols is divided into subsets B0 & B1 with increased minimum square distance. Error performance of level 1 is determined by the minimum square distance of the original partition. Then in order to increase “free Euclidean distance,” coding (combination of block or convolutional) is performed to the lower level. Hence the total error performance is improved. Example (16QAM): Code rate, R = (1/2+3/4+23/24+1)/4=3.2/4 B1 B0 C2 C0 C1 C3 Level 3
  26. 26. B.5 HOW REPEATERS EXTEND THE RANGE
  27. 27. 27 AVIAT NETWORKS | Passive Reflector "Billboard" Site A Single Reflector Site B Terrain Obstruction Passive Repeater Arrangements Site B Site A Terrain Obstruction Terrain Obstruction Double Reflector Double Reflector July 2013
  28. 28. 28 AVIAT NETWORKS | Site A Beam Bender (Back-To-Back Parabolics) Terrain Obstruction Site B Beam Bender Back-To-Back Parabolic Antennas "Beam Bender" Other Passive Repeater Arrangements July 2013
  29. 29. B.6 MICROWAVE TOWER ISSUES
  30. 30. Twist and Sway 30 AVIAT NETWORKS | July 2013 A B C Antennas: HSX12-77 Antennas: HSX12-77 Beamwidth: ±0.35o Beamwidth: ±0.35o 425ft/130m 200ft/60m 425ft/130m Daytime Tower Twist: ±10 ±0.50 deflection angle at 10 dB point
  31. 31. B.7 CAUSES OF MICROWAVE DISCONNECT PERIODS
  32. 32. Causes of Traffic Disconnect - Outage 32 AVIAT NETWORKS | • Rain outage (predictable and therefore acceptable) in access links above about 10 GHz • Equipment failure within the MTBF (Mean Time Between Failure) period • Maintenance error or manual intervention (e.g., failure of a locked-on module or path) • Infrastructure failure (e.g., antenna, batteries, towers, power system) • Low fade margin in non-diversity links • Power fade (long-term loss of fade margin) in paths above about 6 GHz July 2013
  33. 33. C. SOME EXAMPLES OF L2 RADIO TECHNOLOGY
  34. 34. Eclipse Intelligent Node Unit • The most compact nodal solution on the market • Single indoor unit supporting multiple radio paths • Hot-swappable radio and data access modules • Support for all traffic types • Cable-less traffic connections • Complete solution in one box 34 AVIAT NETWORKS | July 2013
  35. 35. • Lower Losses than Couplers • More ODUs per Antenna feed • Fewer Antennas • Increased system gain • Reduces antenna sizes • Less Tower Loading • Radios’ features • 5 to 38 GHz licensed operation • Fully transparent to payload • Up to 500 Mbit/s of TDM, Hybrid TDM/Ethernet/IP, or all-IP throughput • QPSK to 256-QAM Networked Radios 35 July 2013AVIAT NETWORKS |
  36. 36. D. WHY PROPAGATION?
  37. 37. Radio Wave Propagation 37 AVIAT NETWORKS | GEO, MEO, and LEO Satellites Sky Wave (MF, HF only) REFRACTED WAVE NON-REFRACTED (k=1) WAVETransmitting Antenna Receiving Antenna Troposphere Ionosphere Microwave link propagation is influenced by REFRACTION, REFLECTION, and DIFFRACTION (not shown) wave propagation. Ground Wave (LF/MF only) True Earth’s Curvature MULTIPATH RAYS July 2013
  38. 38. Ray Tracing Along a Profile July 201338 AVIAT NETWORKS | • Not unlike outbound ripples from a pebble tossed into a quiet pond, the outgoing microwave wave front is circular. However, the only part of the wave of interest is equal to the diameter (aperture) of the antenna. Beyond the antenna’s near field, and into the far field, the wave front is flat, as shown. The ray(s), one direct (shown) plus multipath rays (if any), are always perpendicular (90o) to the wave front - thus only one ray is assigned to each direct or multipath route. All path profiles and engineering are based upon ray analysis. • Antennas serve only to provide maximum coupling of the direct ray energy into the waveguide feeder, to the exclusion of multipath rays. Thus, optimum dish alignment is crucial for minimum fading. k = 1 (True Earth’s Radius) Superrefraction (k>3) Wavefront Ray 90o Substandard Refraction (k<1) Possible Obstruction Possible Decoupling, Defocusing, or Entrapment Dry and High Valleys Humid Wetlands
  39. 39. Carrier Ethernet Link Design Parameters 39 Flushing ANSI values AVIAT NETWORKS | • NETWORK LAYOUT • FIELD VERIFICATION • MICROWAVE EQUIPMENT (Backhaul Capacity, Link Aggregation, RF Band, Diversity) • LINK ANALYSIS (Google Map Study, Field Survey, Geometry, Weather Patterns) • LINK PERFORMANCE CALCS (ITU, Vigants) • LINK AVAILABILITY CALCS (RF Protection, Rain Outage) • ACTIVE NODES and PASSIVE REPEATERS • FREQUENCY STUDY (Interference, Licensing, Antenna Selection) • INFRASTRUCTURE (Shelter, AC/DC Power, Site Security, Towers, Ice Shield, Air Con, etc.) • ANTENNA FEEDER SYSTEM, (Structures, Aesthetics, Transmission Lines) • GROUNDING AND SAFETY Towers >200ft (60-m) Require Lighting, Painting Sections: 20-ft guyed, 25-ft Self Supp Shelter Elliptical Waveguide, Coax Atmospheric Multipath Millimeter Wave Rain Attenuation Refraction, k-Factor Variations Antenna Sizes, Types, Alignment Diversity Type, Ant. Spacing, XPIC Path Clearance July 2013 Dust Cloud
  40. 40. Multipath Propagation 40 AVIAT NETWORKS | Excessive Path Clearance Elevated Super-refractive Layer Specular Reflection July 2013
  41. 41. E. ANTENNAS AND FEEDER SYSTEMS
  42. 42. 42 AVIAT NETWORKS | Reflector Antennas Photos courtesy of Andrew Corporation July 2013 Standard parabolic Standard parabolic (with radome) Shielded with radome (high performance) Higher F/B ratio Spillover Effect Scattering Effect Diffraction Effect
  43. 43. 43 July 2013
  44. 44. 44 AVIAT NETWORKS | Antennas • Used to efficiently radiate/receive the energy towards/from the far-end of the link • Important characteristics – Gain / directivity / beamwidth – Side lobe level – Front-to-back ratio (F/B) – Polarization (linear V/H, circular, dual V/H) – Cross-polar discrimination – VSWR – Frequency operating range – Mounting, weight, and wind loading – Aesthetics July 2013
  45. 45. 45 AVIAT NETWORKS | Antenna Alignment Issues Antenna aligned on a side-lobe Correct antenna alignment July 2013
  46. 46. 46 AVIAT NETWORKS | Antenna Decoupling • Angle of arrival may vary by as much as 1° on long paths in humid areas at night; therefore larger antennas are typically slightly uptilted during daytime periods • Such variations may cause power fades and degraded performance (loss of fade margin, increased outage) if antennas are very directive Variation in arrival angle K= K=4/3 K=-2 July 2013
  47. 47. 47 AVIAT NETWORKS | PRESSURIZED (AIR) COAXIAL CABLE UNPRESSURIZED (FOAM) COAXIAL CABLE ELIPTICAL WAVEGUIDE RECTANGULAR (RIGID) WAVEGUIDE CIRCULAR (RIGID) WAVEGUIDE Transmission Lines July 2013
  48. 48. 48 AVIAT NETWORKS | Transmission Lines (Feeder Systems) • Coaxial cable • Air dielectric (lower loss) • Foam dielectric (higher loss) • Works from DC, but losses increase very rapidly above 2GHz • Waveguide • Elliptical (very common) • Circular (very low loss) • Rectangular (now rarely used) • Flexible/twistable waveguide • Frequencies below cut-off do not propagate through waveguide July 2013
  49. 49. F. RF PROTECTION
  50. 50. Definitions 50 AVIAT NETWORKS | • Protection Schemes provide a level of security from long- term (>10 CSES/event – Consecutive Severely Errored Seconds) outages and loss of data throughput, and therefore improve Availability and reduce traffic disconnects. • Diversity Arrangements reduce the number and duration of short-term (<10 CSES/event) outages (no traffic disconnects) and therefore improve Performance. July 2013
  51. 51. F.1 MONITORED HOT STANDBY
  52. 52. 1+1 Monitored Hot Standby Outdoor Node (cont’d) July 201352 AVIAT NETWORKS | Tribs 1-20 Protection Cable ODU 600sp/hp/ep Y-Cables
  53. 53. 1+1 Monitored Hot Standby Outdoor Node July 201353 AVIAT NETWORKS | Equal split (3dB) RF Splitter is also possible with the consequence of a 2dB link gain penalty which translates into a 58% degradation in the hop’s error performance and perhaps larger antennas! ANTENNA DATA OUT DATA IN -1.6dB -6.6dB Tx A Rx A Tx B Rx B Asymmetric RF Coupler INU/IDU errorless data selection is frame-by-frame -1.6dB -1.6dB Tx A or Tx B is on line
  54. 54. H.2 MONITORED HOT STANDBY WITH SPACE DIVERSITY
  55. 55. July 201355 AVIAT NETWORKS | Space Diversity with Horizontal Offset
  56. 56. 1+1 Monitored Hot Standby Space Diversity - Outdoor Node July 201356 AVIAT NETWORKS | Multipath forms essentially in the vertical plane; consequently, the antennas should always be placed vertically to achieve de- correlated paths ! Main ANTENNA DATA OUT DATA IN Tx A Rx A Tx B Rx B INU errorless data selection is frame-by-frame Diversity ANTENNA 300 ms Vertical antenna spacing from 3 – 23m ITU-R P.530-13 RSLM RSLD -40 dB fade -20 dB fade
  57. 57. THANKS YOU AND SUGGESTIONS
  58. 58. Suggestions 58 AVIAT NETWORKS | July 2013 • Professional Affiliations News Websites • IEEE • LinkedIn www.bbc.com www.foxnews.com • Movies www.elpais.es • The Pirates of Silicon Valley • Social Network • The Internship • The Greatest Game Ever Played • Flash of Genius • Countries • Spanish English • Chile Australia • Argentina New Zealand Dubai Canada USA
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