[SPA] Esta tesis doctoral se presenta bajo la modalidad de compendio de publicaciones. Los sistemas de localización de los dispositivos que forman el Internet de las Cosas (loT) se basan, habitualmente, en sistemas satelitales (GNSS). Sin embargo, debido a la dificultad que tienen las ondas electromagnéticas de atravesar las paredes y techos de los edificios, los sistemas satelitales no ofrecen una precisión adecuada en interiores de edificios. Por lo tanto, no pueden ser empleados en aplicaciones como localización, navegación o guiado de personas en estos entornos. Al no poder emplearse los sistemas de localización satelitales, se han desarrollado diversas propuestas, algunas propietarias y otras de ámbito científico, que permiten la localización de dispositivos loT en entornos indoor. Estas propuestas emplean tecnologías tan diversas como imagen, radiofrecuencia, sensores inerciales, sensores de campo magnético, e incluso señales acústicas. En esta tesis nos centraremos en los sistemas basados en radiofrecuencia, dado que se trata de los más ampliamente utilizados. Dentro de los sistemas basados en radiofrecuencia, dependiendo de la infraestructura empleada y del propósito del mismo, se pueden emplear diferentes tecnologías para su funcionamiento, entre ellas destacan: WiFi, Zigbee, UWB o Blueetooth Low Energy. La tecnología WiFi ha sido una de las predominantes a la hora de implementar los sistemas de localización en interiores, sobre todo en grandes edificios con gran número de visitantes como son aeropuertos, centros comerciales, museos, etc. Esto se debe a que en este tipo de instalaciones suele existir una amplia red WiFi desplegada para dotar de conectividad a los visitantes. Esta red puede ser empleada a su vez para la generación de sistemas de localización, ahorrando así el despliegue de nueva infraestructura. Se ha de tener cuenta que el coste del despliegue de infraestructura, incluyendo equipos, cableado, ingeniería, etc., suele ser una de las tareas más costosas dentro de cualquier proyecto de ingeniería. Es por ello que se tiende a reutilizar las redes WiFi-existentes dotándolas de otras funcionalidades, además de la propia de conectividad. Una de las principales clasificaciones de los sistemas de localización suele dividir a los mismos entre sistemas activos y pasivos. Los sistemas activos requieren la intervención del dispositivo a localizar mediante una aplicación y/o proceso que recoge información del espectro RF a su alcance, mientras que los sistemas pasivos recogen la señal RF de los dispositivos loT que detectan, pero no requieren de su participación. Durante el desarrollo de esta tesis se ha trabajado en los dos tipos de sistemas, estando dividida la investigación en dos partes claramente diferenciadas. En la primera parte de la tesis se ha trabajado en los sistemas de localización pasivos, concretamente en sistemas de localización mediante la técnica conocida como radar monopulso empleando el estándar WiFi 802.11. Posteriormente se trabajó en la técnica radar monopulso en campo cercano y, a continuación, se combinó con sistemas de ranging basados en el estándar 802.llmc. Mediante la combinación de ambas tecnologías se generó un sistema de localización empleando un único punto de acceso (AP). Por último, el trabajo final de este bloque empleó antenas de haz con escaneo en frecuencia, técnicas de channel-hopping y el algoritmo MUSIC para ampliar el FoV de los dispositivos pasivos implementados en el trabajo anteriore. En la segunda parte de la tesis se ha trabajado en la implementación de un IPS (lndoor Positioning System) de smartphones para grandes superficies, empleando únicamente los APs que ya se encuentran instalados y con una precisión zonal a nivel tienda/pasillo. El IPS es una de las piezas fundamentales de un mecanismo mayor conocido como Sistema de Marketing Contextual. Junto con la descripción detallada del IPS, se explican todos los componentes e intercambios de información entre los diferentes bloques que forman el Sistema de Marketing Contextual. [ENG] This doctoral dissertation has been presented in the form of thesis by publication. the location and positioning systems involved in the Internet of the Things (IoT) paradigm are generally based on satellite systems (GNSS). However, because the electromagnetic waves have difficulties getting through the walls and roof of the buildings, the satellite systems do not have enough accuracy indoors. Therefore, this kind of system cannot be employed in the location and navigation of IoT devices or people indoor. Because satellite tracking systems cannot be employed, several proposals are focused on overcoming the indoor location of IoT devices. Some proposals are from the scientific area, and some other proposals are proprietary. These proposals employ different technologies like image-based, radiofrequency, inertial sensors, magnetic field sensors, and acoustic signals. This Ph.D. thesis will focus on radio frequency-based systems because they are the most frequently used. Among the radio frequency-based systems, several technologies can be employed according to the infrastructure employed and the purpose of the project. These technologies are WiFi, Zigbee, UWB, or Bluetooth Low Energy. WiFi technology has been one of the most employed in indoor location systems, particularly in large infrastructures with a high number of visitors such as airports, malls, museums, etc. This is mainly because there is often a wide WiFi network already deployed to provide connectivity to visitors in this kind of infrastructure. This network could also be employed to implement the location system, saving savings in deploying the system. It should be taken into consideration that the main cost of any project is the infrastructure deployment phase, where the wiring and the new equipment acquisition are carried out. Because of the aforementioned cots, the WiFi networks are often reused with other applications than the data connectivity. One of the main classifications of the indoor location system usually divides them into active and passive. The active systems require the participation of the device to be located by using an app that collects the data from the RF within the range. However, the passive systems collect the RF signal of the IoT devices within the range but do not require their involvement. In this thesis, we have worked on the two kinds of systems. In the first chapters, we have worked in the passive location systems, mainly in the WiFi RADAR monopulse function-based systems based on the 802.11 standard. Next, we focused on the near-field monopulse technique, and later we merged this technique with a ranging system based on the 802.11mc standard. The last work of this section employed a frequency beam antenna with channelhopping techniques and the MUSIC algorithm to increase the FoV of the previously implemented devices. In the following chapters, we work on implementing a smartphone Indoor Positioning System (IPS) for large infrastructures. One of the main premises of our IPS is the use of the already deployed APs with zonal accuracy. The IPS is one of the key enabling technologies of a Marketing Contextual System. Moreover, the component and information flows between the different blocks that make up the Contextual Marketing System are explained. [ENG] This doctoral dissertation has been presented in the form of thesis by publication. The location and positioning systems involved in the Internet of the Things (IoT) paradigm are generally based on satellite systems (GNSS). However, because the electromagnetic waves have difficulties getting through the walls and roof of the buildings, the satellite systems do not have enough accuracy indoors. Therefore, this kind of system cannot be employed in the location and navigation of IoT devices or people indoor. Because satellite tracking systems cannot be employed, several proposals are focused on overcoming the indoor location of IoT devices. Some proposals are from the scientific area, and some other proposals are proprietary. These proposals employ different technologies like image-based, radiofrequency, inertial sensors, magnetic field sensors, and acoustic signals. This Ph.D. thesis will focus on radio frequency-based systems because they are the most frequently used. Among the radio frequency-based systems, several technologies can be employed according to the infrastructure employed and the purpose of the project. These technologies are WiFi, Zigbee, UWB, or Bluetooth Low Energy. WiFi technology has been one of the most employed in indoor location systems, particularly in large infrastructures with a high number of visitors such as airports, malls, museums, etc. This is mainly because there is often a wide WiFi network already deployed to provide connectivity to visitors in this kind of infrastructure. This network could also be employed to implement the location system, saving savings in deploying the system. It should be taken into consideration that the main cost of any project is the infrastructure deployment phase, where the wiring and the new equipment acquisition are carried out. Because of the aforementioned cots, the WiFi networks are often reused with other applications than the data connectivity. One of the main classifications of the indoor location system usually divides them into active and passive. The active systems require the participation of the device to be located by using an app that collects the data from the RF within the range. However, the passive systems collect the RF signal of the IoT devices within the range but do not require their involvement. In this thesis, we have worked on the two kinds of systems. In the first chapters, we have worked in the passive location systems, mainly in the WiFi RADAR monopulse function-based systems based on the 802.11 standard. Next, we focused on the near-field monopulse technique, and later we merged this technique with a ranging system based on the 802.11mc standard. The last work of this section employed a frequency beam antenna with channelhopping techniques and the MUSIC algorithm to increase the FoV of the previously implemented devices. In the following chapters, we work on implementing a smartphone Indoor Positioning System (IPS) for large infrastructures. One of the main premises of our IPS is the use of the already deployed APs with zonal accuracy. The IPS is one of the key enabling technologies of a Marketing Contextual System. Moreover, the component and information flows between the different blocks that make up the Contextual Marketing System are explained. Esta tesis doctoral se presenta bajo la modalidad de compendio de publicaciones. Está formada por estos seis artículos: 1. J. L. Gómez-Tornero, D. Cañete-Rebenaque, J. A. López-Pastor and A. S. Martínez-Sala, "Hybrid Analog-Digital Processing System for Amplitude-Monopulse RSSI-Based MiMo WiFi Direction-of-Arrival Estimation," in IEEE Journal of Selected Topics in Signal Processing, vol. 12, no. 3, pp. 529-540, June 2018, doi: 10.1109/JSTSP.2018.2827701. 2. J. A. López-Pastor, A. Gómez-Alcaraz, D. Cañete-Rebenaque, A. S. Martinez-Sala and J. L. Gómez-Tornero, "Near-Field Monopulse DoA Estimation for Angle-Sensitive Proximity WiFi Readers," in IEEE Access, vol. 7, pp. 88450-88460, 2019, doi: 10.1109/ACCESS.2019.2925739. 3. J. A. López-Pastor, P. Arques-Lara, J. J. Franco-Peñaranda, A. J. García-Sánchez and J. L. Gómez-Tornero, "Wi-Fi RTT-Based Active Monopulse RADAR for Single Access Point Localization," in IEEE Access, vol. 9, pp. 34755-34766, 2021, doi: 10.1109/ACCESS.2021.3062085. 4. J. A. López-Pastor, A. J. Ruiz-Ruiz, A. J. García-Sánchez, and J. L. Gómez-Tornero, “An automatized contextual marketing system based on a wi-fi indoor positioning system,” Sensors, vol. 21, no. 10, pp. 1–26, 2021 5. J. A. Lopez-Pastor, A. J. Ruiz-Ruiz, A. S. Martinez-Sala, and J. Luis Gomez-Tornero, “Evaluation of an indoor positioning system for added-value services in a mall,” in 2019 International Conference on Indoor Positioning and Indoor Navigation (IPIN), 2019, pp. 1–8 6. A. Gil-martínez, M. Poveda-garcía, J. A. López-pastor, J. C. Sánchez-aarnoutse, and J. L. Gómez-tornero, “Wi-Fi Direction Finding with Frequency-Scanned Antenna and Channel-Hopping Scheme,” IEEE Sens. J., vol. XX, no. Xx, pp. 1–9, 2021. Escuela Internacional de Doctorado de la Universidad Politécnica de Cartagena Universidad Politécnica de Cartagena Programa de Doctorado en Tecnologías de la Información y las Comunicaciones