Joaquim Oller

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Bluetooth Low Energy (BLE) is an emerging low-power wireless technology developed for short-range control and monitoring applications that is expected to be incorporated into billions of devices in the next few years. This paper describes the main features of BLE, explores its potential applications, and investigates the impact of various critical(More)
The use of duty-cycling in Medium Access Control (MAC) protocols effectively helps improving the energy efficiency of wireless networks. However, while the benefits of these protocols are unquestionable, most of them still suffer from overhearing and idle listening, two issues that prevent duty-cycled systems from achieving optimum energy usage, which is a(More)
Energy-efficient operation is a challenge for wireless sensor networks (WSNs). A common method employed for this purpose is duty-cycled operation, which extends battery lifetime yet incurs several types of energy wastes and challenges. A promising alternative to duty-cycled operation is the use of wake-up radio (WuR), where the main microcontroller unit(More)
Duty-cycled Medium Access Control (MAC) protocols certainly improve the energy efficiency of wireless networks. However, most of these protocols still suffer from severe degrees of overhearing and idle listening. These two issues prevent optimum energy usage, a crucial aspect in energy-constrained wireless networks such as wireless sensor networks (WSNs).(More)
The next wave driving the expansion of the Internet will come from the Internet of Things. Bluetooth LE is a rapidly emerging ultra-low-power radio technology expected to be incorporated in billions of IoT devices in the next few years. Consequently, it is particularly important to specify Internet connectivity solutions for Bluetooth LE. In this article we(More)
Energy-efficient communication is one of the main concerns of wireless sensor networks nowadays. A commonly employed approach for achieving energy efficiency has been the use of duty-cycled operation of the radio, where the node's transceiver is turned off and on regularly, listening to the radio channel for possible incoming communication during its(More)
Smart cities are a hot topic nowadays for several reasons. For city managers and citizens a smart city is a concept that should allow providing better services and/or with more efficiency. For technicians a smart city represents one of the large-scale deployments of equipment for data capturing, storage and processing. For Internet researchers a smart city(More)
Today, the vast majority of personal communication devices, such as laptops and smartphones, and logically Wi-Fi Access Points (APs), feature IEEE 802.11 chipsets. In turn, Wake-up Radio (WuR) systems are used to reduce the significant energy waste that wireless devices cause during their idle communication mode. In this letter, we introduce a novel WuR(More)
Wake-up radios present a promising alternative to traditional duty-cycle approaches, by reducing overhearing and by eliminating idle listening completely. However, energy-efficient operation of the wake-up mechanism is required for the success of such systems. In particular, addressing is an important component of the wake-up procedure that can consume a(More)
In some use cases, a persistent end-to-end connection between a given data source and a destination may never be present. Consequently, traditional routing protocols cannot be directly applied for delivering data. One example are Wireless Sensor Networks (WSN), due to the limited capabilities of the connected nodes and the lack of a reliable connection(More)