TAILIEUCHUNG - Lecture Wireless and mobile computing – Chapter 23: Coding and error control

The following will be discussed in this chapter: Digital communication system, channel coding, types of error control, why use error-correction coding, types of channel coding, requirement of CC and EC, channel En-De/Coding for wireless communication,. | Coding and Error Control Lecture 23 Digital Communication System Information Source Source Encoder Channel Encoder Modulator Channel Demodu- lator Channel Decoder Source Decoder Data Sink rb rc rs JPEG, MPEG, etc. RS code, Turbo code, QPSK, QAM, BPSK, etc. Cryptography (Ciphering) Source Coding Compression Coding Line Coding Error Control Coding Error Correction Coding Error Detection Coding - Secrecy/ Security - Encryption (DES) - Redundancy removal: - Destructive (jpeg, mpeg) - Non-destructive (zip) - Makes bits equal probable - Strives to utilize channel capacity by adding extra bits - for baseband communications - RX synchronization - Spectral shaping for BW requirements - error detection - used in ARQ as in TCP/IP - feedback channel - retransmissions - quality paid by delay = FEC - no feedback channel - quality paid by redundant bits FEC: Forward Error Correction ARQ: Automatic Repeat Request DES: Data Encryption Standard How Stuff Works Channel Coding Channel coding refers to the class of signal transformation designed to improve communication performance by enabling the transmitted signals to better withstand the effects of various channel impairments. Channel coding can be partitioned into two areas, waveform (or signal design) coding and structured sequences (or structured redundancy.) Waveform coding deals with transforming waveforms into “better waveforms,” to make the detection process less subject to errors. Structured sequence deals with transforming data sequences into “better sequences,” having structured redundancy. Types of Error Control Before we discuss the detail of structured redundancy, let us describe the two basic ways such redundancy is used for controlling errors. Error detection and retransmission, utilizes parity bits (redundant bits added to data) to detect that an error has been made and requires two-way link for dialogue between the transmitter and receiver. Forward error correction (FEC), requires a one way link .

• Quản trị mạng
• Mobile computing
• Wireless and mobile computing
• Services data
• Wireless communication
• Error control
• Digital communication system
• Transmission fundamentals
• Mobile computing transmission fundamentals
• Mobile computing simulations
• Network simulation
• Addressing routing
• Visualization tool
• Signals for conveying information
• Digital data transmission
• Mobile systems
• Mobile services
• Lecture Electronic commerce
• Electronic commerce
• Define mobile commerce
• Personal digital assistant
• Wireless mobile computing
• Lecture Mobile applications overview
• Mobile applications overview
• Mobile computing devices
• Mobile applications becoming ubiquitous
• Mobile cloud computing
• Mobile web services
• Cloud computing
• Medical cloud multi agent system
• New mobile medical
• Introduction to Mobile Cloud Computing
• MCC Architecture
• Advantages of MCC
• MCC Applications
• MCC Issues
• Error detection
• Cyclic Redundancy Check
• Software defined radio
• Satellite communications
• Satellite foot print
• Wireless LAN technology
• Electromagnetic radiation spectrum
• Wireless media standards
• Requirement of protocol
• OSI model
• Protocol suit
• Network access layer
• Transport layer