Decoding Options for the Symmetric and Asymmetric Turbo-Coded Two-Way Relay Channel

In this paper, we extend our recent work on joint decoding of trellis codes for the two-way relay channel to quaternary decoding of turbo codes and evaluate two approaches for rate adaptation. More specifically, we consider the uplink phase, which has been identified as the bottleneck, and apply a quaternary joint turbo decoder for both packets. For asymmetric channels, we evaluate two methods of adapting the code rate while keeping the standard LTE turbo codes. The first approach applies puncturing which is known in LTE as rate matching and adapts the codeword lengths while the second, less well-known, method reduces the message length and is known as expurgatio

A robust resource allocation algorithm for packet BIC-UFMC 5G wireless communications

In this paper, we present a novel resource allocation (RA) algorithm for packet Universal Filtered Multi-Carrier (UFMC) BIC-based communications, the latter being a novel modulation format possibly envisaged to be applied in 5G wireless systems. Assuming the perfect knowledge of the channel and capitalizing on the specific UFMC signal waveform, the proposed RA strategy optimizes the coding rate and bit loading within the overall bandwidth along with the per-subband power distribution. In the presence of a carrier offset and over fading selective channels, the results we obtained are twofold: i) the UFMC format reveals to be more robust than the conventional OFDM scheme; ii) the performance of the UFMC system itself is further boosted by the optimal choice of radio resources evaluated by the proposed RA algorithm

D11.2 Consolidated results on the performance limits of wireless communications

Deliverable D11.2 del projecte europeu NEWCOM#The report presents the Intermediate Results of N# JRAs on Performance Limits of Wireless Communications and highlights the fundamental issues that have been investigated by the WP1.1. The report illustrates the Joint Research Activities (JRAs) already identified during the first year of the project which are currently ongoing. For each activity there is a description, an illustration of the adherence and relevance with the identified fundamental open issues, a short presentation of the preliminary results, and a roadmap for the joint research work in the next year. Appendices for each JRA give technical details on the scientific activity in each JRA.Peer ReviewedPreprin

UNIVERSAL FILTERED MULTICARRIER (UFMC): FROM THEORY TO PRACTICE

In questa tesi viene descritto lo sviluppo della forma d'onda chiamata Universal Filtered Multicarrier (UFMC), tra le maggiori candidate a diventare il livello fisico della prossima generazione di rete cellulare 5G. A differenza dell'OFDM, questa forma d'onda multiportante raggruppa le sottoportanti in sottobande, dove il segnale viene elaborato e filtrato. In questo modo, l'UFMC riesce a fornire un ulteriore grado di libertà in termini di flessibilità, oltre che migliorare la robustezza del segnale contro disallineamenti temporali e frequenziali. Dato che in letteratura non viene menzionata nessuna tecnica di allocazione delle risorse applicata all'UFMC, sono state proposte diverse strategie capaci di migliorare ulteriormente le prestazione della forma d'onda, massimizzando un parametro di qualità chiamato goodput, in comunicazioni con pacchetti di piccola dimensione, sia in caso di perfetta che imperfetta sincronizzazione. Questi metodi si basano sulla scelta dei migliori parametri di trasmissione, rappresentati dal tasso di codifica, modulazione, potenza e numero di simboli multicarrier trasmessi, usando un algoritmo iterativo greedy e sfruttando la granularità della forma d'onda. Inoltre, viene mostrata un implementazione dell'UFMC tramite l'utilizzo di un framework di sviluppo open-source chiamato OpenAirInterface. L'implementazione è avvenuta sul canale dati uplink PUSCH dello standard LTE, sostituendo il modulatore OFDM con un modulatore UFMC a bassa complessità computazionale mentre al ricevitore è stato utilizzato il classico ricevitore PUSCH OFDM, semplicemente aggiungendo un blocco di sincronizazione temporale in maniera tale da permettere la ricezione del segnale UFMC. I risultati ottenuti in termini di block error rate e di complessità computazionale hanno dimostrato e confermato le qualità della forma d'onda UFCM nello scenario di applicazione tipico, specialmente in caso di sincronizzazione non perfetta

Network Coding and Decoding Options for Trellis-coded Relay Communications

I study the application of trellis codes to physical layer network coding in relay communications, with two, three or four users. In particular, I consider non-binary decoding on a combined trellis as an alternative to binary decoding and evaluate its gain in several scenarios, including asymmetric channels and the combination of different codes. I focus on the multiple-access phase, in which the terminals transmit their messages simultaneously, while in the second phase the relay will retransmit the network-coded combination of every messages. I also evaluate the performance of both options for the decoding of the individual message of each terminal

Decoding options for trellis codes in the two-way relay channel

We study the application of trellis codes to physical-layer network coding in the two-way relay channel. In particular, we consider quaternary decoding on a combined trellis as an alternative to binary decoding and evaluate its gain in several scenarios, including asymmetric channels and the combination of different codes. We focus on the multiple-access phase, in which both terminals transmit their messages simultaneously, while in the second phase the relay retransmits the network-coded combination of both messages. We also evaluate the performance of both options when decoding the individual message of each terminal. © 2013 IEEE

Universal filtered multicarrier for machine type communications in 5G

Machine to machine (M2M) and Internet of things (IoT) communication systems are characterized by short and bursty communication cycles. Devices may also have very low duty cycles to increase battery lifetime. Current 4G systems are not adapted to these kind of traffic characteristics. Even to send just a short packet, a user equipment (UE) first needs to synchronize to the network, establish a connection through a random access procedure, and further requires some higher layer signaling to establish end-to-end connectivity. The reduction of latency and the reduction of energy consumption are some of the key requirements for 5G communication systems. In order to achieve these requirements changes to several elements of the rotocol stack are required. In this paper we are going to discuss several possible solutions for the PHY and the MAC layer. We focus on the experimental evaluation of these solutions based on the OpenAirInterface platform

Propensity score matched analysis of postoperative nausea and pain after one anastomosis gastric bypass (MGB/OAGB) versus sleeve gastrectomy (SG)

: The aim of our study was to assess and compare postoperative nausea and pain after one anastomosis gastric bypass (OAGB) and sleeve gastrectomy (LSG). Patients undergoing OAGB and LSG at our institution between November 2018 and November 2021 have been prospectively asked to report postoperative nausea and pain on a numeric analogic scale. Medical records were retrospectively reviewed to collect scores of these symptoms at the 6th and 12th postoperative hour. One-way analysis of variance (ANOVA) was used to evaluate effect of type of surgery on postoperative nausea and pain scores. To adjust for baseline differences between cohorts, a propensity score algorithm was used to match LSG patients to MGB/OAGB patients in a 1:1 ratio with a 0.1 tolerance. A total number of 228 (119 SGs and 109 OAGBs) subjects were included in our study. Nausea after OAGB was significantly less severe than after LSG both at the 6th and 12th hour assessment; pain was less strong after OAGB at the 6th hour but not after 12 h. Fifty-three individuals had a rescue administration of metoclopramide after LSG and 34 after OAGB (44.5% vs 31.2%, p = 0.04); additional painkillers were required by 41 patients after LSG and 23 after OAGB (34.5% vs 21.1%, p = 0.04). Early postoperative nausea was significantly less severe after OAGB, while pain was comparable especially at the 12th hour

A COSMIC-FFP Based Method to Estimate Web Application Development Effort

In the paper we address the problem of estimating the effort required to develop dynamic web applications. In particular, we provide an adaptation of the Cosmic Full Function Point method to be applied on design documents for counting data movements. We also describe the empirical analysis carried out to verify the usefulness of the method for predicting web application develop- ment effort