Recent Advancements in Turbo Coding with Interleave Division Multiple Access (IDMA) Technique
| Autor: | Poonam Chauhan, G. K. Upadhyay, Iosr Journals, Deepti Shastri |
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| Rok vydání: | 2014 |
| Předmět: | |
| Zdroj: | IOSR Journal of Electronics and Communication Engineering. 9:08-13 |
| ISSN: | 2278-2834 2278-8735 |
| DOI: | 10.9790/2834-09240813 |
| Popis: | Turbo-codes have attracted a great deal of interest since their discovery in 1993. This paper reviews the reasons for this, in particular their attainment of the ultimate limits of the capacity of a communication channel. Turbo-codes promise the attainment of the ‘Holy Grail’ of communication theory, sought for nearly half a century to achieve the ultimate limits of capacity of a communication channel. It is not surprising, therefore, that they have very rapidly moved from the research laboratories to find practical application throughout the world and beyond it. Following their announcement in 1993, they have found a very wide range of applications, mainly in wireless communications, ranging from the third generation mobile systems to deepspace exploration. Now there is lots of advancement take place in turbo codes by the use of interleave division multiple access. The interleaver combines the output of turbo decoders. Several new interleaver designs for turbo codes are presented which illustrate the important role that the interleaver plays in these codes. The relationship between turbo codes and Low density parity check codes is explored via an explicit formulation of the parity-check matrix of a turbo code, and simulation results are given for sum product decoding of a turbo code. Our discussion encompasses analysis and optimization techniques, superposition-coded modulation, frequency domain processing schemes and the applications of IDMA in multiple-input multiple-output, relay and ad hoc environments. We demonstrate the flexibility and robustness provided by IDMA. We show that the IDMA principle can be applied to realize many potential performance gains highlighted by information theory, including coding gain, diversity gain and multi-user gain. We demonstrate that these gains can be very high, ranging from a few to tens of dBs, compared with conventional approaches. Keyword: Interleavers, iterative decoding, low-density parity-check codes, convolutional codes, turbo codes |
| Databáze: | OpenAIRE |
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