Cable 101. A Broadband Telecommunications Primer for Non-technical Personnel

Transcription

1 Cable 101 KnowledgeLink, Inc. A Broadband Telecommunications Primer for Non-technical Personnel Presented by: Justin J. Junkus President, KnowledgeLink, Inc. November 20, 2013

2 Agenda Broadband Cable Systems How They re Put Together Architecture What s Between Subs and Signals System Bandwidth Evolution and Growth Delivering Today s Service How Services Get to Subscribers Triple Play and More Digital Delivery 2

3 At the end of this training, you will be able to: Describe a typical cable telecommunications network Name the 5 subsystems of a cable network State the purpose of amplifiers and lasers Explain what is meant by system bandwidth Describe some uses of the reverse path Explain the difference between an analog signal and a digital signal Describe how digital services are routed through a broadband cable system Point out possible network causes of system malfunctions 3

4 History Cable Telecommunications began with CATV - Community Antenna TeleVision Why CATV? - Mountains - Rural Communities

5 Beginnings CATV - Community Antenna Television Ed Parsons Astoria, OR - Twin Lead - Housetop to Housetop Bob Tarton Lansford, PA - Coaxial Cable - Telephone Poles

6 Today: Definition of a Cable System A cable system is the collection of media and electronic apparatus designed to collect, process, and distribute signals, typically at radio frequencies, between a central location (Headend) and remote locations, typically customer s homes.

7 Terminology: Media Coaxial Cable Solid or Braided Shield (Foil Shield) Dielectric Jacket Center Conductor 75 ohms

8 Terminology: Media Optical Fiber COATING CLADDING CORE

9 Terminology: Signals Off-air Satellite/Fiber Sourced Local Programming VOD Ads HS Data Voice Telephony 9

10 Terminology Radio Frequency Sine Wave /2 Cycle 1/2 Cycle TIME 1 Cycle Low Frequency Most Content High Frequency Most Distribution

11 Terminology Hertz One Cycle per Second KHz - 1,000 hertz MHz - 1,000,000 hertz GHz - 1,000,000,000 hertz Radio Frequencies

12 Traditional CATV Model Architecture Five Subsystems: Hub Supertrunk Line Extender Hub Headend Trunk Feeder/ Distribution Drop Terminal

13 What are those triangles?? Cable Characteristics Lossy Medium, causes attenuation Signal Strength Distance

14 Amplifiers Compensate for Loss Gain and the Amplifier ONE WAY

15 Unity Gain A Tap 2 B Signal Value at B = Signal Value at A

16 Terminology Decibel db Measure of Signal Strength Remember These Rules! - 1/2 Power = 3dB Loss - 2 X Power = 3dB Gain

17 Noise Limits Application of Gain + Attenuation + 17

18 Noise Limits Application of Gain Noise Ratios Carrier to Noise (CNR) Signal to Noise (SNR) FCC Standards (at set top box): C/N... not less than 43 db 18

19 Hybrid Fiber Coax (HFC) Traditional Cable HFC

20 Traditional CATV Model Architecture Five Subsystems: Hub Supertrunk Line Extender Hub Headend Trunk Feeder/ Distribution Drop Terminal

21 Headend

22 Headend Elements - Classic Antennas Receivers Processors Modulators/Demodulators Conditional Access - Scramblers/Descramblers, Encryption/ Decryption Frequency Converters Local Origination Equipment Ad Insertion Equipment Combiners

23 Headend Elements New Services Cable Modem Termination System (CMTS) Servers Routers Storage

24 Inside the Headend

25 Inside the Headend - Now 25

26 Hub: Extension of Head End Optical to Electrical Conversion Modulators for Off-Air Signals Frequency Converters VOD Servers QAM Modulators CMTS

27 Trunk System Components Strand Cable Connectors Amplifiers Passive Components Line Power Inserters Splitters Directional Couplers Surge Suppressers

28 Distribution/Feeder System Components Strand Cable Connectors Bridgers Directional Couplers Taps Line Extenders

29 Drop System Drop Cable Connectors Bonding Equipment Splitters Traps Network Interface Units

30 Terminal Equipment Television Set VCR Stereo Receiver DVD Player Personal Video Recorder Cable Modem Router Gateway Laptop/Desktop Home Network Phone

31 Network Interconnections: Evolution to Fiber Coax Tree and Branch Headend/Hub Configuration Headend Interconnects Fiber Nodes

32 Simple Tree and Branch

33 Headend/Hub

34 Headend Interconnect via Fiber

35 Fiber Node

36 Fiber Node Functions Conversion Between Optical and Electrical Signals Physical Interface of the Coax to the Fiber Optic Plant

37 Fiber Node: Inside the Box Typical: Fiber management Reverse transmitter Optical receiver Equalizers and pads Filters Transponder Power supply Fuse Test points KnowledgeLink, Inc. (630)

38 What s Next? RFoG 38

39 Cable Bandwidth Evolution How We Grew from 12 channels to Broadband Cable

40 Signal Building Block Sine Wave + 0-1/2 Cycle 1/2 Cycle TIME 1 Cycle

41 Modulation Amplitude Modulation Frequency Modulation Ampltude Modulation

42 History of 6 MHz. Channels Three Separate Sine Waves Carry Video Video Carrier Audio Carrier Color Carrier 1.25 MHz 3.58 MHz 6 MHz 4.5 MHz

43 Analog Carrier

44 Downstream Bandwidth Channel 2 Analog Video Services 54 MHz

45 First Generation System Spectrum Allocation All Downstream ^ 5 Frequency, MHz ^ 450

46 Cable Characteristics Lossy Medium, causes Attenuation Tilt Signal Strength Distance Frequency

47 Equalization Compensates for Tilt Equalization

48 System Sensitivities Signal quality Signal to Noise Ratio Carrier to Noise Ratio Amplifier settings(gain) Subscriber connections Cable faults 48

49 Second Generation Genesis PEG System Testing Early Pay Per View 49

50 Second Generation System Spectrum Allocation ^ ^ 5 42 Frequency, MHz ^ 450 Low Split Return: 5-42 MHz. Guard Band: 8 Mhz.

51 Second Generation System Two Way Capability Forward Path TWO WAY Reverse Path

52 Two Parts to Amplifier Design Forward Path A Tap 2 B Signal Value at B = Signal Value at A

53 Reverse Path Design Complicated by: Funnel Effect Ingress

54 The Funnel Effect Signals Add A Different Design from Forward Path Design Multiple Signal Sources

55 Reverse Path Compensating for the Funnel 2 A B 1 Adjust Signal at B so that Input At A is at Specified Level Depends on Path B-A Path B-A Differs for Every Return Each path must be adjusted

56 Ingress A Dirty Little Animal

57 Ingress Sources Where Does Ingress Come From?

58 Ingress Effects Signal Degradation Bandwidth Consumption Delays in Data Transmission

59 Canceling Ingress Traps and Filters

60 Additional System Sensitivities 2 nd Gen Systems Reverse path 60

61 Third Generation Driven by Service Demand I Want to do more and go faster!! 61

62 Third Generation System Increased Bandwidth and New Services ^ ^ ^ Frequency, MHz ^ 450 ^ 750

63 Hybrid Fiber Coax (HFC) 63

64 Additional System Sensitivities 3 rd Gen Systems Laser levels 64

65 Fourth Generation: Service Demand on Steroids I Want to do more and go faster!! 65

66 Fourth Generation System Video Digitization and More Bandwidth ^ ^ ^ Frequency, MHz ^ 550 ^ 700 ^ 750 ^ 1 GHz and Beyond

67 Analog Signals vs. Digital Signals 67

68 Analog Signals vs. Digital Signals 68

69 The Digital Challenge Use an Analog Transmission Plant for Digital Data Answer: Modulation!

70 Fourth Generation System Digital: a Different Way to Carry Signals Analog Signal Digital Signal Source: Tektronix QAM Modulated Sine Carrier

71 Digitization Removes Limitations

72 Additional System Sensitivities A whole new set of digital metrics 72

73 BREAK TIME 73