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Operations on the 5G‐NR and 4G‐long‐term evolution (LTE) frequency bands make it possible to increase cell coverage and/or improve data rate transmission on the uplink (UL) and the downlink. Dynamic Spectrum Sharing is a technology that allows the deployment of both 4G LTE and 5G‐NR in the same frequency band. Carrier aggregation (CA) consists of adding different 5G‐NR radio channels. CA increases the bandwidth by combining several carriers. The radio channel aggregation notation determines the bandwidth class of the radio channel by the aggregation of multiple DC radio channels and the Fallback Group. The maximum 5G carrier band depends on the band number and numerology. Carrier aggregation increases radio data rates by adding the bandwidth of each CC radio channel. The supplementary UL bandwidth is generally smaller than the traditional band, but the carrier frequency is lower, thereby improving cell coverage for the uplink.

System information broadcasts radio characteristics of the cell, radio characteristics of neighboring cells and alerts. System information consists of a master information block (MIB) message and a series of system information block (SIB) messages. The MIB message is transmitted in the synchronization signal block. The MIB provides the information needed by the mobile to read the physical downlink shared channel. The SIB2 message provides the common information relating to the re‐selection of intra‐/inter‐frequency and inter‐radio access technology cells. The paging procedure consists of transmitting a notification to the mobile in the radio resource control (RRC)_IDLE state or in the RRC_INACTIVE state to inform it of incoming data. Connection reconfiguration messages are used to modify an existing RRC connection. In standby mode, the measurement configuration is broadcast by the gNb base station in the SIB 1 message. The measurements made on the server cell and neighboring cells are used for cell selection and handover.

The initial deployment of the 5G service is based on 5G‐non‐standalone access option 3, also called dual EN‐DC connectivity. The selection of the 4G radio access network is initiated by the mobile. The synchronization signal identifies the cell with the physical layer cell identit. Cell re‐selection is also based on the public land mobile network priority list stored in the Universal Subscriber Identity Module module. The random access procedure is said to be with contention when the mobile randomly chooses the resources. The mobile synchronizes on the PCell of the target en‐gNB entity and performs the random access procedure without contention. The NG interface management procedure allows NG‐C interoperability information to be exchanged between the next‐generation radio access network node and the core network. A bandwidth part is a contiguous set of physical resource blocks, selected from a contiguous subset of the common resource blocks for a given numerology on a given carrier.

The multiple input multiple output (MIMO) mechanism improves radio data rate by performing spatial multiplexing of multiple signals. Beamforming is a complementary mechanism to MIMO. Beamforming logically reduces the beam opening angle and limits the level of interference between cells. Elevation beamforming allows a beam to be directed in a specific way, for example, a beam pointing either up or down. The transmission modes implementing beamforming and the multi user‐MIMO mechanism require good correlation between the antennas. The MIMO mechanism and the beamforming mechanism are based on knowledge of the propagation channel. Symbols produced by modulation are distributed over spatial layers, and then precoded before being assigned to resource elements by antenna port. Only the orthogonal frequency division multiplexing signal allows the MIMO mechanism to operate up to four spatial layers or the beamforming mechanism by digital precoding.

A BandWidth part (BWP) corresponds to an allocation of resources in the frequency domain. The initial BWP corresponds to a 5G‐NR sub‐band on which the mobile user equipment (UE): searches for the synchronization signal block. The size of the BWP depends on the number of Physical resource blocks and the numerology. The mobile camps on a cell which broadcasts the SSB block and the system information block type 1 (SIB1) information allowing the mobile to find the configuration of the initial BWP partition. The concept of control resource SET (CORESET) was introduced on the 5G‐NR interface to limit the control frequency domain to the capacities of devices. The configuration of the CORESET is transmitted to the mobile UE via Radio Resource Control messages. The initial BWP is transmitted to the mobile by the broadcast information MIB and SIB1.

OFDM modulation consists of modulating orthogonal subcarriers. OFDM modulation offers good spectral efficiency and provides resilience to the frequency selective fading of the propagation channel. OFDM modulation has been implemented on the long‐term evolution radio interface. The 5G‐NR time division duplexing frame provides flexibility in the direction of radio resources per slot: OFDM symbols in a slot can be up, down or flexible. The dynamic configuration corresponds to the sequencing of the transmission of the mobile based on the control signal downlink control information. The physical primary synchronization signal ensures the synchronization of the OFDM signal and the time synchronization at the half‐frame level. The physical secondary synchronization signal provides time synchronization at the frame level. The physical random access channel contains a preamble used by the mobile to ask for the establishment of a radio bearer.

The 5G‐standalone access architecture requires the deployment of a 5G core network connected to the next‐generation radio access network (NG‐RAN). The NG‐RAN provides both NR and LTE radio access. The NG‐RAN provides both an LTE radio interface and a 5G‐NR radio interface. The NG‐RAN node is responsible for managing radio resources, controlling the radio bearer establishment of the user plane and managing mobility during the session. The NG‐RAN node performs compression and encryption of traffic data on the radio interface. The mobile and the AMF exchange data using the non‐access stratum protocol. The AMF manages the addition and removal of the transport network layer association with the entities of the NG‐RAN node. The AMF is in charge of managing the 5G core network and services. The security architecture implemented on the 5G mobile is based on mutual authentication between the 5G core network core network and mobile.

The data link layer is made up of four sublayers: service data adaptation protocol, packet data convergence protocol (PDCP), radio link control (RLC), and medium access control (MAC). Connectivity to a data network through 5G‐NR radio access and the 5G Core network is provided by a packet data unit session. PDCP is used for radio resource control (RRC) signaling messages, relative to dedicated control data, and for traffic Internet Protocol (IP) packets. The PDCP provides the following functions: the security of RRC traffic and signaling data, and sequence numbering and sequential delivery of RRC messages and IP packets. The IP packet may be subject to the robust header compression header compression to reduce the relative weight of headers. The RLC protocol provides control of the radio link between the mobile and the gNB entity. The MAC protocol defines a header for multiplexing RLC frames from different instances and from MAC protocol control elements.

Some conservation prioritization methods are based on the assumption that conservation needs overwhelm current resources and not all species can be conserved; therefore, a conservation triage scheme (i.e., when the system is overwhelmed, species should be divided into three groups based on likelihood of survival, and efforts should be focused on those species in the group with the best survival prospects and reduced or denied to those in the group with no survival prospects and to those in the group not needing special efforts for their conservation) is necessary to guide resource allocation. We argue that this decision-making strategy is not appropriate because resources are not as limited as often assumed, and it is not evident that there are species that cannot be conserved. Small population size alone, for example, does not doom a species to extinction; plants, reptiles, birds, and mammals offer examples. Although resources dedicated to conserving all threatened species are insufficient at present, the world's economic resources are vast, and greater resources could be dedicated toward species conservation. The political framework for species conservation has improved, with initiatives such as the UN Sustainable Development Goals and other international agreements, funding mechanisms such as The Global Environment Facility, and the rise of many nongovernmental organizations with nimble, rapid-response small grants programs. For a prioritization system to allow no extinctions, zero extinctions must be an explicit goal of the system. Extinction is not inevitable, and should not be acceptable. A goal of no human-induced extinctions is imperative given the irreversibility of species loss.Asignación de Recursos para la Conservación, Resiliencia de Poblaciones Pequeñas y la Falacia del Triaje de Conservación Resumen Algunos métodos de priorización de la conservación están basados en el supuesto de que las necesidades de la conservación superan a los actuales recursos y que no todas las especies pueden ser conservadas; por lo tanto, se necesita un esquema de triaje (esto es, cuando el sistema está abrumado, las especies deben dividirse en tres grupos con base en su probabilidad de supervivencia y los esfuerzos deben enfocarse en aquellas especies dentro del grupo con las mejores probabilidades de supervivencia y a aquellas en el grupo sin probabilidades de supervivencia o aquellas en el grupo que no necesita esfuerzos especializados para su conservación se les deben reducir o negar los esfuerzos de conservación) para dirigir la asignación de recursos. Discutimos que esta estrategia para la toma de decisiones no es apropiada porque los recursos no están tan limitados como se asume con frecuencia y tampoco es evidente que existan especies que no puedan ser conservadas. Por ejemplo, tan sólo un tamaño poblacional pequeño no es suficiente para condenar a una especie a la extinción; contamos con ejemplos en plantas, reptiles, aves y mamíferos. Aunque actualmente todos los recursos dedicados a la conservación de todas las especies amenazadas son insuficientes, los recursos económicos mundiales son vastos y se podrían dedicar mayores recursos a la conservación de especies. El marco de trabajo político para la conservación de especies ha mejorado, con iniciativas como los Objetivos de Desarrollo Sustentable de la ONU y otros acuerdos internacionales, el financiamiento de mecanismos como el Fondo para el Medio Ambiente Mundial, y el surgimiento de muchas organizaciones no gubernamentales mediante programas de subsidios pequeños hábiles y de respuesta rápida. Para que un sistema de priorización no permita las extinciones, las cero extinciones deben ser un objetivo explícito del sistema. La extinción no es inevitable y no debería ser aceptable. El objetivo de cero extinciones inducidas por humanos es imperativo dada la irreversibilidad de la pérdida de especies.

A controversy at the 2016 IUCN World Conservation Congress on the topic of closing domestic ivory markets (the 007, or so-called James Bond, motion) has given rise to a debate on IUCN's value proposition. A cross-section of authors who are engaged in IUCN but not employed by the organization, and with diverse perspectives and opinions, here argue for the importance of safeguarding and strengthening the unique technical and convening roles of IUCN, providing examples of what has and has not worked. Recommendations for protecting and enhancing IUCN's contribution to global conservation debates and policy formulation are given.

Sparse Code Multiple Access (SCMA) is a technique to improve spectral efficiency by sharing the same spectral resources among different users. As a result, the receiver has to cope with excess interference. A channel encoder is used to aid receiver to correct the data stream. In this paper, we discuss the use of an LDPC encoder for channel coding on each user’s traffic, followed by an SCMA encoder. SCMA encoder is a potential candidate for fifth generation (5G) mobile communication and different codebooks have already been proposed. In this paper we choose specific codewords extracted from permutation of QPSK modulation and rotation. The receiver is based on Log Domain Message Passing Algorithm (Log-MPA) for SCMA. The novelty of our paper lies in the receiver scheme with exchange of extrinsic information between SCMA decoder and LDPC decoder. Feedback from LDPC decoder provides extrinsic information to SCMA decoder, thus enabling creation of a super-graph between LDPC and SCMA decoder. Numerical results depict performance gain in terms of Bit Error Rate (BER) and complexity over conventional LDPC coded SCMA systems.

International audience; This technical note deals with the study of uplink (from the mobile phone to the base station) transmitted power control in Long Term Evolution (LTE). It provides a nonlinear Potential Feedback Control (PFC) for scalar discrete-time systems with input delays and disturbances by using the Lyapunov theory and the Artstein transform. It is an original approach in which a stabilization problem of a linear scalar system with a constraint on the state space is transformed into a problem of nonlinear stabilization. We use this strategy of stabilization for the uplink transmission power control in LTE.

Humans depend on biodiversity in myriad ways, yet species are being rapidly lost due to human activities. The ecosystem services approach to conservation tries to establish the value that society derives from the natural world such that the true cost of proposed development actions becomes apparent to decision makers. Species are an integral component of ecosystems, and the value they provide in terms of services should be a standard part of ecosystem assessments. However, assessing the value of species is difficult and will always remain incomplete. Some of the most difficult species' benefits to assess are those that accrue unexpectedly or are wholly unanticipated. In this review, we consider recent examples from a wide variety of species and a diverse set of ecosystem services that illustrate this point and support the application of the precautionary principle to decisions affecting the natural world.

International audience; This article deals with a new Quality of Service (QoS) aware Two-Level Scheduler (TLS) for real-time (RT) data flows in downlink transmission of Long Term Evolution (LTE) cellular networks. It consists of two distinct scheduler levels. At the upper-level scheduler, the Potential Feedback Controller (PFC) determines the quota of data to transmit in order to meet the delay constraints of RT data flows while, at the lower-lever scheduler, the Proportional Fair (PF) scheduler is used to reach a high fairness among Users (UEs). The PFC is well suited for the upper-level scheduler since it maintains the queue length as close as possible to zero which leads to a low Packet Loss Ratio (PLR). A comparison, by using LTE-Sim simulator, with well-known QoS aware scheduling methods Frame Level Scheduler (FLS), Exponential (EXP)-rule and Logarithmic (LOG)-rule has been provided which shows that our proposed TLS outperforms the EXP-rule and LOG-rule scheduling methods and it slightly decreases the PLR of RT data flows compared to the FLS scheduling method while it significantly reduces the computation time.