This article deals with OFDM transmission associated with turbo codes, in order to realize a software radio modem with several waveforms. Except for the frequency transposition, we show that all the functions can be implemented as software. This modem is adapted for HF, VHF and UHF transmission, depending on the chosen waveform. Simulations and tests in real condition achieve a bit error rate o...

—In this paper, we demonstrate the higher hardware ef ciency of Reed-Solomon (RS) parallel turbo decoding compared with BCH parallel turbo decoding. Based on an innovative architecture, this is the rst implementation of fully parallel RS turbo decoder. A performance analysis is performed showing that RS Block Turbo Codes (RS-BTC) have decoding performance equivalent to Bose Ray-Chaudhuri Hocque...

Turbo equalizers have been shown to be successful in mitigating the effects of inter-symbol interference introduced by partial response modems and by dispersive channels for code rates of 1 2. In this contribution, we comparatively studied the performance of a range of binary phase-shift keying turbo equalizers employing block-turbo codes, namely Bose–Chaudhuri–Hocquenghen turbo codes, convolut...

This paper addresses some critical implementation issues involved in the development of a turbo decoder, using the UMTS specification as a concrete example. The assumption is that the decoder is to be implemented in software rather than hardware, and thus a variable number of decoder iterations is not only possible, but desirable. Three twists on the decoding algorithm are proposed: (1) A linea...

Infrared wireless communication and optical communication usually adopt on-off keying (OOK) and pulse position modulation (PPM). In [1] we presented the iterative maximum a posteriori probability (MAP) decoding of Turbo coded OOK and Turbo coded binary PPM (BPPM). In this paper, we present a soft-output Viterbi algorithm (SOVA) based iterative decoding of Turbo coded OOK and Turbo coded BPPM. W...

Basically, conventional single-carrier system has an advantage in limited power communication systems. However, the performance of conventional single-carrier system is seriously degraded by ISI (inter-symbol interference). In order to overcome the ISI, communication systems are commonly used an equalizer. Turbo equalization technique was proposed to maximize system performance over ISI channel...

In this paper we don't examine security of Turbo SHA-2 completely; we only show new collision attacks on it, with smaller complexity than it was considered by Turbo SHA-2 authors. In [1] they consider Turbo SHA-224/256r and Turbo SHA-384/512-r with variable number of rounds r from 1 to 8. The authors of [1] show collision attack on Turbo SHA-256-1 with one round which has the complexity of 2. F...

Turbo code is recommended as a channel coding scheme, which has been shown to be capable of performing close to the Shannon Limit. In this paper, we compare the performance of both convolutional and block turbo codes over AWGN and Rayleigh fading channels. It is observed that the performance of convolutional turbo code is slightly better in the water fall region and the coding gain ranges from ...

This paper describes a diagnostic software package called Turbo Tester. It contains a variety of tools related to the area of digital test. The range of tools includes test generators, logic and fault simulators, test optimizer, hazard analyzer, built-in self-test simulators, and design error diagnosis tools. The range of compatible diagnostic tools forms, via their interaction and complementar...