A comparative study on the modified Max-Log-MAP turbodecoding by extrinsic information scaling

A simple but effective technique to improve the performance of the Max-Log-MAP algorithm is to scale the extrinsic information exchanged between two MAP decoders. A comprehensive analysis of the selection of the scaling factors according to channel conditions and decoding iterations is presented in this paper. Choosing a constant scaling factor for all SNRs and iterations is compared with the best scaling factor selection for changing channel conditions and decoding iterations. It is observed that a constant scaling factor for all channel conditions and decoding iterations is the best solution and provides a 0.2-0.4 dB gain over the standard Max- Log-MAP algorithm. Therefore, a constant scaling factor should be chosen for the best compromise.

Book review: Jiří Přibáň, legal symbolism: on law, time and European identity

This is a book review of Jiří Přibáň, Legal Symbolism: On Law, Time and European Identity, Ashgate, Aldershot, 2007, 226 pp, ISBN: 978-0-7546-7073-5

Book review: Philosophy and the city: classic to contemporary writings

Book Review: Philosophy and the City: Classic to Contemporary Writings Sharon M. Meagher (Ed.), 2007 Albany, NY: State University of New York Press 309 pp. US$75.50 hardback; US$24.95 paperback ISBN 978 0 7914 7308 5 paperback; 978 0 7914 7307 8 hardback

Increasing the speed of parallel decoding of turbo codes

Turbo codes experience a significant decoding delay because of the iterative nature of the decoding algorithms, the high number of metric computations and the complexity added by the (de)interleaver. The extrinsic information is exchanged sequentially between two Soft-Input Soft-Output (SISO) decoders. Instead of this sequential process, a received frame can be divided into smaller windows to be processed in parallel. In this paper, a novel parallel processing methodology is proposed based on the previous parallel decoding techniques. A novel Contention-Free (CF) interleaver is proposed as part of the decoding architecture which allows using extrinsic Log-Likelihood Ratios (LLRs) immediately as a-priori LLRs to start the second half of the iterative turbo decoding. The simulation case studies performed in this paper show that our parallel decoding method can provide %80 time saving compared to the standard decoding and %30 time saving compared to the previous parallel decoding methods at the expense of 0.3 dB Bit Error Rate (BER) performance degradation.

Small Press Book Fair

This was held on 20 February 2015. It attracted around 25 small presses, and around 100 attendees.

Book review: New perspectives on the Irish abroad: the silent people?

Review of Mícheál Ó hAodha and Máirtín Ó Catháin eds., New perspectives on the Irish Abroad: The silent people? Lanham, Md.; Toronto: Lexington Books, 2014,166 pages. ISBN-13: 978-0739183717