What is meant by convolution coding?
9.4. 3 Convolutional coding. Convolutional coding is a widely used coding method which is not based on blocks of bits but rather the output code bits are determined by logic operations on the present bit in a stream and a small number of previous bits.
What are the main blocks of convolutional code?
Block Diagram for Convolutional Code. The major elements of the convolutional coding technique include the shift register that acts as temporary storage and whose stored bits undergo shifting using a sliding window, a logic circuit that performs modulo-2 addition incorporating X-OR function.
What are the advantages of convolutional codes?
The main benefits I gathered from using convolutional codes is that, it’s easy to implement and does better (than linear codes) in cases where you have higher error probability rates and noisy channels. Information bits are spread along the sequence. Lastly, these codes have memory.
What is packet binary convolutional coding?
PBCC is an optional method of error protection which may be used in IEEE (Institute of Electrical and Electronics Engineers) 802.11 networks. Its support within a network is broadcast in the beacon message.
What are the applications of convolution code?
The puncturing technique uses standard rate one by two encoders and decoders. The main applications of convolution coding is in the deep space applications and in wireless communication systems.
Is convolution code better than cyclic code?
It doesn’t have any memory. Cyclic codes have more codes as compared to the convolution code. Cyclic code, information bit is kept like a block. This code works lower than convolution code but those two achieves the same quality.
What is meant by linear code?
In coding theory, a linear code is an error-correcting code for which any linear combination of codewords is also a codeword. A linear code of length n transmits blocks containing n symbols. For example, the [7,4,3] Hamming code is a linear binary code which represents 4-bit messages using 7-bit codewords.
Is convolution code a block code?
In block codes, information bits are followed by parity bits. In convolution codes, information bits are spread along the sequence. Block codes are memoryless whereas Convolution codes have memory. Convolution codes use small codewords in comparison to block codes, both achieving the same quality.
What are the different methods of describing the structure of a convolutional code?
There are several methods for representing a convolutional encoder in graphical form; they include the state transition diagram, the tree diagram, and the trellis diagram. As a convention, in the state transition and trellis diagrams, a solid line represents an input 1, whereas a dashed line represents an input 0.