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In this manuscript global research trends are analyzed in agent-based modeling (ABM), which is applied to face the inherent complexity of agricultural systems. The search was carried out in Scopus, during the period 2009-2019, and the VOSviewer© software was used as a bibliometric tool. The results show that ABM is used under two approaches: research and policy evaluation, and in three thematic areas: systems and computation sciences, geography and ecology and environmental science. The purpose of this study is to investigate three types of phenomena: land-use changes, water management and agricultural policy evaluation. ABM has been shown to be useful for exploring and understanding the society-nature relationship of agricultural systems under an interdisciplinary and transdisciplinary approach, and for supporting decision-making processes via its application in a Latin American context, which for our purposes is still of utmost importance. Resumen En este manuscrito se analizan las tendencias globales en investigación de la modelación basada en agentes -MBA- aplicada para abordar la complejidad inherente a los sistemas agropecuarios. Se emplea la búsqueda en Scopus, durante el período 2009-2019, y el software VOSviewer© como herramientas bibliométricas. Los resultados obtenidos muestran que MBA se aplica bajo los enfoques de investigación y de evaluación de política en tres áreas temáticas principales: ciencias de la computación y sistemas, geografía, y ciencias ambientales y ecología; y para estudiar esencialmente fenómenos de cambios en el uso de la tierra, gestión del agua y evaluación de políticas agrícolas. Aunque MBA ha demostrado ser una herramienta teórica útil para explorar y comprender la interrelación sociedad-naturaleza de los sistemas agropecuarios desde enfoques inter y transdisciplinarios, así como para soportar los procesos de toma de decisiones, su aplicación en el contexto latinoamericano es aún incipiente.

We are witness, and actors, in a changing world, different from that proceed and unpredictable, whose main characteristic is its complex nature. A changing world with a level of unprecedented interconnectedness and interdependence (cause of its complexity), with new structures (networks) and new social technologies that shape the Internet as a transformation digital infrastructure and also of adequation. As a result, a “new expanded and complex vital environment”, has a significant impact in the way we interact, live, work and learn. We are therefore facing a new class of situations or problems (complex) that, when we face the same, we need not only change how we think and perceive reality (systems thinking), but also the adoption of a new digital culture, where interdependence and sustainability prevails. We call “complexity gap”, the difficulty that entails the assimilation and practise of such requirements, which at the same time represents the main challenge we are faced with today. Referred to as “complexity gap”, the difficulty involved in the assimilation and practice of these requirements and, in turn, is the main challenge we face today. Finally, from an of organic growth perspective (“bottom-up”), considering the person as “complex adaptive system”, it is proposed profile “eAprendiz” as a strategy for adaptation and personal, and professional, empowerment, in the current global “extended and complex environment”. Finally, from an organizational development (“bottom-up”), and considering the person as “complex adaptive system”, it is proposed profile “eAprendiz” as a strategy for adaptation and personal, and professional, empowerment, in the current global, extended and complex environment., Estamos siendo testigos, y a la vez actores, de un mundo en transformación, distinto del que procedemos e impredecible, cuya característica principal es su naturaleza compleja. Un mundo en transformación con un nivel de interconexión e interdependencia sin precedentes (causa de su complejidad), con nuevas estructuras (redes) y con nuevas tecnologías sociales, que configuran a Internet como infraestructura digital de transformación (disruptiva) y, también, de adecuación. Como resultado de todo ello, un “nuevo ENTORNO vital, expandido y complejo”, impacta notablemente en la manera en que nos relacionamos, vivimos, trabajamos y aprendemos. Nos encontramos, pues, ante una nueva clase de situaciones o problemas (complejos) que, a la hora de enfrentarnos a los mismos, nos requiere no solo cambiar nuestra forma de pensar y percibir la realidad (pensamiento sistémico), sino también la adopción de una nueva cultura digital, de interdependencia y sostenibilidad. Denominamos como “brecha de la complejidad”, a la dificultad que conlleva la asimilación y práctica de dichos requerimientos y que, a su vez, constituye el principal reto al que nos enfrentamos en la actualidad. Por último, desde una perspectiva de desarrollo orgánico (“bottom- up”), y considerando a la persona como “sistema complejo adaptativo”, se propone el perfil “eAprendiz” como estrategia de adecuación y empoderamiento personal, y profesional, en el actual entorno global, “extendido y complejo”.

Signal distortions in communication systems occur between the transmitter and the receiver; these distortions normally cause bit errors at the receiver. In addition interference by other signals may add to the deterioration in performance of the communication link. In order to achieve reliable communication, the effects of the communication channel distortion and interfering signals must be reduced using different techniques. The aim of this paper is to introduce the fundamentals of Orthogonal Frequency Division Multiplexing (OFDM) and Orthogonal Frequency Division Multiple Access (OFDMA), to review and examine the effects of interference in a digital data communication link and to explore methods for mitigating or compensating for these effects.