Showing papers by "Giuseppe Caire published in 1994"
28 Nov 1994
TL;DR: It is shown that the iterated product of single-parity-check (SPC) codes shows that their weight distribution asymptotically approaches that of random coding if the smallest code length in the product approaches infinity.
Abstract: We consider the iterated product of single-parity-check (SPC) codes. We show that their weight distribution asymptotically approaches that of random coding if the smallest code length in the product approaches infinity. According to a specific criterion, the best choice consists of taking all SPC codes of equal length. Estimates of the weight distribution obtained by simulation show that even moderately long codes have a weight distribution close to that obtained in the average by random coding. We also discuss decoding of these codes by iterated replication decoding and report results of its simulation.
33 citations
TL;DR: In this article, experimental tests were carried out in order to ascertain the biomass activity in a biological fluidized bed reactor and the results clearly put in evidence as the activity is strongly effected by liquid-solid mass transfer and support roughness which in turn determines the compactness of biofilm and its diffusive properties.
14 citations
TL;DR: The power density spectrum of block-coded modulated signals is computed and sufficient conditions for this spectrum to be the same as for uncoded modulation are derived.
Abstract: The power density spectrum of block-coded modulated signals is computed. Sufficient conditions for this spectrum to be the same as for uncoded modulation are derived. In the special case of a PSK-based-scheme, necessary conditions are derived in order to achieve spectrum shaping. The spectral lines obtained may be used for block synchronization. >
11 citations
TL;DR: The geometrical uniformity properties of signal space codes generated by multilevel coded modulation are considered and an easy-to-test criterion for finding if a given signal set obtained as the union of two orbits of the same generating group has the uniform distance property is provided.
Abstract: We consider the geometrical uniformity properties of signal space codes generated by multilevel coded modulation. First we examine multilevel schemes based on 2/sup L/-ary PSK signal sets, and we derive conditions on the binary component codes which lead to geometrically uniform signal space codes. Next we study the geometrical uniformity of multilevel schemes based on signal sets having a generating group isomorphic to a direct product. Finally, we provide an easy-to-test criterion for finding if a given signal set (or signal space code) obtained as the union of two orbits of the same generating group has the uniform distance property. >
5 citations
27 Jun 1994
TL;DR: Investigates the structure of linear block codes defined over cyclic groups Z/sub q/ (q=p/sup L/ with p prime), i.e., of the subgroups of (Z/ sub q/)/sup n/.
Abstract: Investigates the structure of linear block codes defined over cyclic groups Z/sub q/ (q=p/sup L/ with p prime), i.e., of the subgroups of (Z/sub q/)/sup n/. Bounds on the Euclidean distance of block-coded modulation schemes associated with these codes are also provided, along with some examples of these schemes. >
4 citations