TRANSMISSION AND SWITCHING SYSTEMS
Elements of digital communication and information theory, model of digital communication system, mutual information and channel capacity of a discrete memoryless channel, calculation of channel capacity of a discrete memory less, Heartlay Shannon law, signal reconstruction in time domain, practical and flat top sampling, sampling of bandpass signal, waveform coding techniques,
Transmission in Telecommunication: Introduction, Need of Transmission, Types of Transmission, Medium and their types, Transmission Line, losses in transmission. Analog and Digital Transmission: Differences, Characteristics of Analog and Digital Transmission, Techniques, Digital TransmissionImpairments, Noise and its types, Methods for removing noise. Power Levels: Concepts, Units of power level, Derivation of power level units, Relative Power Levels, Conversion between different power units, Power level representation diagrams, Calculation of power levels, Line diagram representation. Transmission Circuits: Two wire circuits Application of two wire circuits, Two to Four wire circuits, Application of two to four wire circuits, Signaling in Transmission circuits, Singing Effect, Circuits for minimizing singing effect, 4 wire radio circuits. Analog Transmission Impairments: Echoes, Effect of Echoes, Talker’s Echo, Listener’s Echo, Attenuation factor, Trans-hybrid loss, Impedance Mismatching, Echo Cancellers. System Stability & Standards: Conditions for System Stability, Stability Margin, ITU Standards, ITU Sectors. Transmission Performance: Telephony Concepts, Overall loudness Rating, Subscriber Loop, Internal Circuits of Telephone, Signaling in Telephony, Signal Transmission in Telephony, Multiple Signals Transmission, Feeding Bridges. Network Structure: Introduction to Network Structures, Need of Networks, Hierarchical Networks, Types of Network, Application of Networks, Exchanges and their need, Junction Networks, Trunking Concept, Toll or Trunk Networks, Multi-Exchange Areas. Network Services: Services, PSTN, Private Circuits, PDN, Tele Services, Bearer Services, Cross-Bar Switches, Need of Cross-Bar Switches, Modes of Cross-Bar Switches, Working of Cross-Bar Switches, Application areas. Telecommunication Switching System: Need of Switching System, Functions, Elements, Types, Centralized Switching,, Single Channel Connection Switching, Fully Interconnected Switching, Hierarchical System, Mesh of Trunk Routes, Conventional Representation of Networks, Stored Program Controller. Network Designing: One stage, two stage, three Stage, multi Stage, Designing of Networks. Signal Exchange Diagrams: Types of Initiating Signals, Seize Signals, Acceptance Signals, Clear Forward Signals, Clear Backward Signals, Flow Diagram for Status Representation, Simplified S.T.D for originating Calls. Call Originating Process: Introduction, Hunting System/Hunting Process, Finding System/Finding Process. Telecommunication Traffic Engineering: Concept of Traffic, Traffic Statistics, Calling Rate, Holding Time, Distribution of Destinations, User Behavior, Average Occupancy, Traffic Pattern, Busy Hour, Peak Busy hour, Time Consistent Busy Hour, Call Completion Rate, Busy Hour Call Attempts, Busy Hour Calling Rate, Day-to-Day hour Traffic Ratio, Units of Traffic, Erlang, Cent calls second (CCS), Cent calls Minutes (CM), Grade of Service, Blocking Probability and Congestion, Random Variables and Randomprocess, Mean of Trials, Variance, Standard Deviation, Call arrival process: poison process.