ample_JPG_RIP_100.jpg,accessed 21 August 2015. [27] ITU. ITU-T H Series: Audiovisual and Multimedia Systems. http://www.itu.int/net/itu-t/sigdb/spevideo/ Hseries-s.htm, accessed 21 August 2015. Error Control Coding Preview Questions Is it possible to know whether bits have been detected erroneously? Is it possible to design an error-free communications system? Is there a limit? How do cyclic redundancy check (CRC) codes work? What are turbo codes? What are LDPC codes? Learning Objectives Importance error control coding in digital telecommunications Error detection coding techniques, in particular cyclic redundancy check (CRC) codes Different forward error correction coding systems, including block and convolu- tional error codes The Shannon limit and the error-free communications threshold Basic processes of data transmission and reception Broadband Telecommunications Technologies and Management, First Edition. Riaz Esmailzadeh. C 2016 Riaz Esmailzadeh. Published 2016 by John Wiley & Sons, Ltd. Companion Website: www.wiley.com/go/BTTM Broadband Telecommunications Technologies and Management Historical Note Error-free transfer and storage of information has been an important aspect of telecommunications for millen- nia. An example is the process of copying holy books (pictured)¹ such as the Bible, where scribes had devel- oped elaborate techniques to ensure the holy text was exactly replicated [1]. These techniques included counting the number of words and letters in each par- agraph and comparing them with the original text. Further accuracy was obtained through counting the number of occurrences of an individual letter of alpha- bet on each page and checking it against the original. Clearly, any discrepancy indicated errors, which could then be searched for and corrected. The accuracy of replicated holy text was clearly of great importance for which such an effort and expense were made. This transfer of information to remote places and time needed to remain true to the original and therefore justified spending t