Francisco Cercas

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The analytical bit error rate of hierarchical quadra5 ture amplitude modulation formats, which include uniform and 6 nonuniform constellations, over flat Rayleigh fading environments 7 is studied in this paper. The analysis takes into account the effect 8 of imperfect channel estimation and considers diversity reception 9 with both independent identically(More)
This paper addresses the problem of controlling the envelope's power peak of single carrier modulated signals, band limited by root-raised cosine (RRC) pulse shaping filters, in order to reduce power amplifier back-off for very small aperture terminals ground stations. Magnitude modulation (MM) is presented as a very efficient solution to the(More)
A multistage polyphase magnitude modulation (MPMM) technique is proposed for single carrier (SC) modulations, to efficiently reduce the peak-to-average power ratio (PAPR) of the bandwidth limited signal resulting from root-raised cosine (RRC) filtering. We show that the application of back-off to the transmitter high-power amplifier (HPA), in order to avoid(More)
Magnitude Modulation is a technique proposed with success for QPSK and OQPSK in order to maximize power and bandwidth of small satellite earth stations, by reducing PAPR of the modulated signal at the HPA input. To meet the ever growing demand for higher data rates, higher order modulations have been considered. This paper shows that it is possible to use(More)
This paper considers the uplink transmission in BS (Base Station) cooperation schemes employing SC-FDE schemes (Single-Carrier with Frequency-Domain Equalization), where MTs (Mobile Terminals) in adjacent cells share the same physical channel. We study the quantization requirements when sending the received signals at different BSs to a central unit that(More)
The presented paper considers the uplink transmission in base station (BS) cooperation schemes where mobile terminals (MTs) in adjacent cells share the same physical channel. We consider single-carrier with frequency-domain equalization (SC-FDE) combined with iterative frequency-domain receivers based on the iterative block decision feedback equalization(More)
In this paper we consider the uplink transmission in BS (Base Station) cooperation schemes where users in adjacent cells share the same physical channel and the signals received by each BS are sent to a CPU (Central Processing Unit) that combines the different received signals associated to a given user and/or performs the user separation. We consider(More)
This paper presents an unified and empirical propagation model to obtain the received power in mixed scenarios, with outdoor and indoor environments, or in a scenario with only one kind of environment, either for an urban, sub-urban or rural scenario, with or without vegetation. This unified model is called the Lisbon University Institute (LUI) one and can(More)
In this paper a novel multistage polyphase magnitude modulation (MPMM) scheme is proposed for efficiently controlling the envelope's peak power of single carrier band limited signals, using root-raised cosine (RRC) pulse shaping. A new LUT-less approach of the concept of magnitude modulation (MM) is developed. As opposed to traditional MM solutions, based(More)
An efficient multistage polyphase magnitude modulation (MPMM) scheme was recently proposed to solve the problem of controlling the envelope's power peak of single carrier modulated signals, band limited by root-raised cosine (RRC) pulse shaping filters, in order to maximize the efficiency of the transmitter's high power amplifier (HPA). This paper addresses(More)