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—In this work we study the effect of oscillator phase noise on the uplink performance of a massive multiple-input multiple-output system. Specifically, we consider an orthogonal frequency-division multiplexing-based uplink transmission and analyze two scenarios: (a) all the base station (BS) antennas are fed by a common oscillator, and (b) each of the BS(More)
In this paper we address the problem of constellation design in four dimensional space (4D) under average power constraint. We compare the performance of best lattice constellations with those optimized without any constraint on their structure. Even though the lattice based constellations provide the best minimum distance, usually they do not allow for a(More)
—We propose a new spread spectrum (SS) system based on continuous-phase modulations (CPMs). The main idea is to exploit the sequence of modulation indices of a multi-h CPM as a frequency-hopping (FH) sequence. Spectral spreading, flatness and smoothness can be easily achieved by an appropriate choice of the maximum value of the modulation index and of the(More)
In frequency division multiplexed (FDM) systems, spectral efficiency can be increased by reducing the spacing between two adjacent channels, thus increasing the relevant interference and possibly accounting for it at the receiver. In this paper, we consider a FDM system where each user employs a continuous phase modulation (CPM), serially concatenated with(More)
In this paper, we investigate the performance of constellations optimized for transmissions in dual-polar mobile satellite applications. These four-dimensional constellations (inphase and quadrature per polarization) are designed for joint transmission over the two polarizations. Such constellations enhance the reliability of the system by providing certain(More)
On-board processing (OBP), a paradigm that allows for manipulation of the signal at the satellite transponder, is being embraced by a large section of the satellite community. Exploiting OBP can lead to efficient implementation, bandwidth saving, lower redundancy, and better performance. Enabling processing aboard a satellite necessitates re-assessing the(More)
One of the proposals to increase the spectral efficiency of the DVB-S2 standard is based on time-frequency packing. This technique causes intersymbol and interchannel interferences to arise, requiring a significant growth of the number of pilots used to carry out frequency and phase synchronization. Therefore, a new pilot design will be introduced and(More)
Emerging markets for satellite communications, such as maritime and aeronautical applications, require reliable communications in challenging conditions and low-cost, lowcomplexity user terminals. In this perspective, the synchronization chain is a fundamental part of the receiver and its design becomes critical. When a quadricorrelator is used as first(More)
Enabling ultra fast systems has been widely investigated during recent decades. Although polarization has been deployed from the beginning in satellite communications, nowadays it is being exploited to increase the throughput of satellite links. More precisely, the application of diversity techniques to the polarization domain may provide reliable, robust,(More)
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