the paper presents lower and upper bounds on the number of parity check digits required for a linear code that detects solid bursts of length $b$ or less and simultaneously any $e$ or less random errors. an example of such a code is also provided. further, codes capable of detecting and simultaneously correcting such errors have also been dealt with.

a brass vortex tube (vt) with interchangeable parts is used to determine the optimum cold end orifice diameter, main tube length and diameter. experiments were carried out to study the effects of operating pressure as well. it is shown that there is an optimum value for cold end orifice diameter, which is equal to 4mm and there is an optimum value for cold and hot exit temperature difference at...

-Third generation wireless system is based on the WCDMA (Wide band Code Division Multiple Access) access technique. In this technique all the users share the same bandwidth simultaneously but with different codes. System transmits from base station to multiple user terminals or from user terminal to base station. WCDMA uses Orthogonal Variable Spreading Factor (OVSF) codes. Each user terminal d...

We present a novel spread spectrum communication system for the secured transmission of digital information. The approach is based on the unconventional self-encoding principles that we have developed at the University of Nebraska for the modulation and detection of spread spectrum signals. The proposed system does not use pseudo-random codes, and is unique in that traditional transmit and rece...

In this paper the performance of diierent coding schemes for direct-sequence spread-spectrum (DS-SS) with multiple-access (MA) interference in a nonselective Rayleigh fading channel is considered. A conventional 64-ary orthogonal code (M 64) transmitting 6 bits of information is examined rst. Each of the 64 code symbols in the M 64 code is assumed to be spread by a random sequence of length N, ...

Recently, new spreading sequences have been proposed to multiplex the capacity of users. In particular, Weyl spreading sequences have the larger capacity of users than the Gold code. This paper shows that Weyl spreading sequences appear in bit recovering model and they are orthogonal basis. This result shows the reason why they have the large capacity and that any spreading sequence is expresse...

The contention-free property of interleavers is one of the key design requirements for the parallel decoding implementations of turbo codes in order to achieve high decoding throughput. Quadratic permutation polynomial (QPP) interleavers are maximum contention-free (MCF), i.e., every factor dividing the interleaver length becomes a possible degree of parallel decoding processing without any mem...