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Hybrid Fiber Coax - Coggle Diagram

- - - - 78 NTSC analog carriers in the 54 MHz to 550 MHz band
      - switched digital video services in the
        200 MHz band between 550 MHz and 750 MHz is
    - - serve 200 to 300 home
      - 135 passings per mile is around $125 per
        subscriber.
      - installed first cost of nearly $215
      - CATV standby power is added to
        increase service reliability, this cost rises to about $148.
    - - fiber-to-the-last-device
      - 2 Gb/s can be delivered to a fiber node using as few as seventy 6 MHz video channels—a standard 750 MHz system has a capacity of 120 video channels
  - - - no collisions occur when the subscribers transmit
        information upstream
      - can use either baseband or RF carrier transmission techniques
    - - Station ranging is not required.
      - more immune to single tone
        interference.
      - more immune to single tone
        interference.
    - - carries the signals for the subscribers
        served by the next section and so forth
        
        another possible 40 or 50 subscribers
- - - - all transmission
        routes will have to be protected
      - route diversity protection on both the downstream and
        upstream link
      - optical transmitters
        will also have to be protected
      - remote network
        powering units internally
        protected
      - Batteries will be needed to protect against short-term power outages
      - damage to the coaxial cable distribution busses that feed the subscriber drops can cause the loss of service to a large number of subscriber
  - - - A manager for the headend.
      - • A status monitor and control system for the distribution electronics.
      - • A system manager for the subscribers’ settop boxes and home communications terminal equipment
  - - - The available bandwidth increases linearly with the reduction in the number of subscribers served by the fiber node
      - 1 Mb/s to 1.5 Mb/s
        per subscriber in the reverse path
      - benefits of a smaller
        service area size plus more efficient modulation
        
        QPSK16 at 275 home node
        
        64 QAM17 at 75 home nodes
    - - Increasing the forward channel bandwidth
      - Employing narrowcasting distribution techniques.
      - Using more efficient modulation techniques.
      - Using combinations of these basic techniques
  - - - use a suitable network interface device to
        connect to the network.
      - information provider and the information user
        must both use compatible equipment
    - - Compressed digital video signal bandwidth requirements will continue to fall as the cost of computer processing power and random access memory (RAM) storage decreases
- - - - Broadband
        Integrated Gateway (BIG)
        
        strips out the compressed digital information from
        the ATM cells
        
        converts the ATM input into a compatible signal
        
        BIG interfaces with the ATM switch using
        SONET OC-3 transport facilities
      - Connection Management Controller (CMC)
        
        provides the BIG with the necessary
        information to take the data from the incoming ATM