Posts

Block Coding of Product Code

Image
 Introduction to Block Coding In forward error control coding (FECC), the information bits are encoded with parity bits though which error correction and detection is are performed at receiver side. One of the main categories of forward error control coding methods is block coding method. In block coding, the block codes are typically a memory-less method that makes the map of “k” input bits to “n” output bits. The extra bits are the parity bits. Block codes are represented as (n, k). In any communication system, the utilization of any channel coding is mostly performed on the expense of other system characteristics. Therefore comparisons are mostly important to make a system that meets the performance needs as well as to adhere the bandwidth and power constraints. The first comparison is in between error performance and bandwidth. The coding of error-correction is implemented to up-scales the error performance, but these techniques require the transmission of extra bits tha...
Post a Comment
Read more

Forward Error Control Coding (FECC) Methods

Image
In the previous post, we discussed that forward error control coding method adds parity bits to protect the information bits without concerning with large bandwidth and slow data rate. It is further classified into broad categories namely, block coding and convolutional coding. 1- Block Coding Block coding is used in all types of digital communications. In this coding technique, the information bits are subdivided in to k-data bits. The encoder transforms each k-bit data block into larger sequence block of n-bits called coded information bits where n > ݇k. The redundant bits are the difference of “n” and “k” which is also called parity bits. The parity bits have no information but these bits are used to correct and detect the bits error. The code is referred to as (n, k) block code and the rate of code block can be determined by the ratio of k and n. 1.1- Encoding To encode a block code having M-rows and N-columns, overall make 8-bit data block. The product of M and N gives k that s...
Post a Comment
Read more

Types of Channel Coding

Image
 Channel coding utilizes parity bits to overcome the effect of different channel faults such as interference of noise and fading in information signal. Channel coding up-scales the performance and efficiency of the transmitter as well as receiver. We have two basic ways to implement the parity for detecting and controlling the errors. These two ways are Automatic Repeat Request (ARQ) and Forward Error Control Coding (FECC). 1- Automatic Repeated Request (ARQ) In automatic repeated request (ARQ) technique, the parity bits are added by the transmitter to information bits which will be used by the receiver for the detection of bits error. In this technique, only transmitter adds parity bits while the receiver does not add parity bits to correct the information bits. The receiver only detects the bits error and sends an alert to transmitter system for the retransmission of information bits called acknowledgment. When receiver detects the bits error, it sends an alert to transmitter for...
Post a Comment
Read more

Basics of Channel Coding

Image
1- Background of Channel Coding: Channel coding is used to detect and correct the information bits. There two common types of channel coding that includes automatic repeated request (ARQ) and forward error control coding techniques. Both are used for channel coding. While there are some demerits of automatic repeated request (ARQ) like in this type of channel coding, only transmitter adds parity bits to code word through which it can only detect errors and cannot correct the errors. To correct the error bits as well, we will use forward error control coding technique that is able to detect and correct error bits. We are given with 16- coding word (0000-1111) that is product code for which we consider the block coding as suitable. In block coding, first we will encode the 16-coding word and then new block code will be decoded at the receiver side which will be our last final result of this report.When the information is sent through communication channel, some extra bits are received at...
Post a Comment
Read more

English Speech for Students : The Life of Holy Prophet (PBUH)

It starts with the great name of Almighty Allah who is the most merciful and most beneficent who is Rahman and Rahim and who gave us the power of speaking honorable chief guests respectable teachers and my dear fellows Assalamu Alaikum! The topic which is declared to me that is the life of the Holy Prophet (Peace Be Upon Him). Respectable chief guest nearly 1400 years ago the people were engaged in cruelty demands, illiteracy, superstition, ignorance and a lot of social evils then Allah Almighty raised the Prophet Muhammad (Peace Be Upon Him) among themselves to bring them in the light of it the Holy Prophet (Peace Be Upon Him) was born at Makkah in 571 AD. He belonged to an Arab tribe called Quraysh, his father name was Abdullah, The Holy Prophet (Peace Be Upon Him) did not do any bad activity from his childhood since up to his whole life helping our poor people was a family of only Prophet (Peace Be Upon Him) people loved his purity after coming of Holy Prophet (Peace Be Upon Hi...
Post a Comment
Read more