Channel encoding deals with error control during the transmission through the communication channel.

Error detection Codes

Parity check codes
Cyclic Redundancy Check Code   (CRC)

Error correction code include Block coding
Block codes: Information symbols are grouped together in blocks for encoding

Fire codes
Repetition code
Linear block code
Single error correcting Hamming code
Cyclic codes: Encoding and decoding can be implemented using shift registers
    and additional small logic.
Bose-Chaudhuri-Hocquenghem (BCH) codes
Golay Codes: only multiple error correcting code.
Reed Solomon Codes: largest possible code minimum distance and error
    correcting capability for any linear code.
Convolutional codes
        Trellis codes
        Turbo codes

Forward Error Correction
Interleaving coding is an effective method to combat error bursts due to fading.

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Modulation is the process in which the carrier signal is modulated according to the information bits. Modulation schemes are as follows:

Amplitude Shift Keying Frequency Shift keying Binary Phase Shift Keying Quadrature Phase Shift Keying Offset QPSK Differential PSK Gaussian Minimum Shift Keying Quadrature Amplitude Modulation M-level QAM Orthogonal Frequency Division Modulation

ASK FSK BPSK QPSK OQPSK DPSK GMSK QAM MQAM OFDM

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Physical Channel: The method of creating physical channels involves allocating the finite resources.

Duplexing methods involves the allocation of the directions of transmission:

Frequency Division Duplexing     Time Division Duplexing

(FDD) (TDD)

Multiple access refers to the method of creating multiple channels for each transmission direction

Frequency Division Multiple Access     Time Division Multiple Access Code Division Multiple Access         Direct Sequence         Frequency Hopping         Carrier Sense multiple access                 Pseudo noise codes                 Walsh codes                 Gold codes

(FDMA) (TDMA) (CDMA) (DS-CDMA) (FH-CDMA) (CS-CDMA) (PN)

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Channel Models: Modeling of transmission impairments such as transmission loss and noise.

Additive White Gaussian Noise Channel     (AWGN)
Raleigh fading Channel
Rician fading Channel
Rice fading channel
Multipath Channel
Narrow band interference

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Digital Filters: Filters to remove the out of band components

Infinite Impulse Response Filter     Finite Impulse Response Filter Hilbert Transform Fast Fourier Transform Inverse Fast Fourier Transform Matched Filters

(IIR) (FIR) (FFT) (IFFT) (MF)

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Demodulation: Inverse process of the modulation

Coherent: Carrier reference is required.
Non-coherent

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Synchronization / Carrier Recovery: In order to demodulate the information bits the locally generated signal should be synchronized with the incoming signal.

Costas Loop Phase Locked Loops Delay Locked Loops Frequency Locked Loops

(PLL) (DLL) (FLL)

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Detection: Finding the information bits

Equalizers
        Constant Modulus algorithm (CMA) equalizer
        Viterbi equalizer

I-Q splitter
Viterbi decoding (Convolutional decoder)
Deinterleaver
Squaring envelope detection
Quadrature envelope detection
Peak signal envelope detection
Linear signal averaging
Peak signal averaging
Exponential averaging

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Data Processing: Processing functions involved in wireless communication

Bit to Symbol converter
Symbol to Bit converter
Frame synchronizer
Bit synchronizer
Bit Error Rate (BER)
Digital correlator
Numerically controlled oscillators (NCOs)
Puncturing
Depuncturing

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