This work is aimed at investigating the use of neural network-based adaptive receivers for synchronous variable bit-rate Multi-Carrier CDMA systems transmitting over low-earth-orbit (LEO) satellite channels. It is known by literature that MC-CDMA techniques are much more resilient with respect to multi-user interference effects in multipath fading channels than single-carrier DS/CDMA ones. More...

Due to the characteristics of underwater acoustic channel, media access control (MAC) protocols designed for underwater acoustic sensor networks (UWASNs) are quite different from those for terrestrial wireless sensor networks. Moreover, in a sink-oriented network with event information generation in a sensor field and message forwarding to the sink hop-by-hop, the sensors near the sink have to ...

The overloaded CDMA schemes exploited in direct sequence CDMA (DS-CDMA) systems are mainly to accommodate a greater number of users than the available spreading factor N . In this paper, a superposition coding CDMA (SPC-CDMA) with unequal error protection (UEP) is proposed as one of the overloaded CDMA schemes for the next generation mobile communication systems. It exploits the available power...

__________ Many mobile satellite systems have been proposed to employ Code Division Multiple Access (CDMA) technique at L/S band. These bands have been allocated to the mobile satellite services on a primary basis since 1992, in addition to the existing services. Therefore, the mobile satellite services will be subject to share spectrum with each other and with existing services. This paper dis...

In code division multiple access CDMA systems direct sequence DS applying maximum ratio combining MRC at the receiver has achieved high interest for mobile communications A second and rather novel technique is orthogonal frequency division multi plexing OFDM applying maximum likelihood detection MLD at the receiver In this paper the performance of both tech niques is compared considering the mo...

Direct detection optical code-division multipleaccess (CDMA) communication systems involving overlapping pulse-position modulation (OPPM) is considered. Double optical hardlimiters placed before and after the correlator at the receiver side is proposed for this system. The performance (in terms of the bit error probability) of this system is evaluated taking into account the effect of both the ...