María José Morón

A wireless monitoring system for pulse-oximetry sensors

This paper presents a wireless medical monitoring system. The system permits to receive and process in a single concentrator node (e.g. a laptop or a simple handheld device) the pulse-oximetry signals from one ore several monitored patients without using any wired infrastructure. The system, which is based on a piconet of Bluetooth sensors, can retransmit the medical signals by WLAN and GPRS. The paper describes the practical application scenarios in which this type of systems could be of great utility.

Analysis of Android Device-Based Solutions for Fall Detection

Falls are a major cause of health and psychological problems as well as hospitalization costs among older adults. Thus, the investigation on automatic Fall Detection Systems (FDSs) has received special attention from the research community during the last decade. In this area, the widespread popularity, decreasing price, computing capabilities, built-in sensors and multiplicity of wireless interfaces of Android-based devices (especially smartphones) have fostered the adoption of this technology to deploy wearable and inexpensive architectures for fall detection. This paper presents a critical and thorough analysis of those existing fall detection systems that are based on Android devices. The review systematically classifies and compares the proposals of the literature taking into account different criteria such as the system architecture, the employed sensors, the detection algorithm or the response in case of a fall alarms. The study emphasizes the analysis of the evaluation methods that are employed to assess the effectiveness of the detection process. The review reveals the complete lack of a reference framework to validate and compare the proposals. In addition, the study also shows that most research works do not evaluate the actual applicability of the Android devices (with limited battery and computing resources) to fall detection solutions.

On the Capability of Smartphones to Perform as Communication Gateways in Medical Wireless Personal Area Networks

This paper evaluates and characterizes the technical performance of medical wireless personal area networks (WPANs) that are based on smartphones. For this purpose, a prototype of a health telemonitoring system is presented. The prototype incorporates a commercial Android smartphone, which acts as a relay point, or “gateway”, between a set of wireless medical sensors and a data server. Additionally, the paper investigates if the conventional capabilities of current commercial smartphones can be affected by their use as gateways or “Holters” in health monitoring applications. Specifically, the profiling has focused on the CPU and power consumption of the mobile devices. These metrics have been measured under several test conditions modifying the smartphone model, the type of sensors connected to the WPAN, the employed Bluetooth profile (SPP (serial port profile) or HDP (health device profile)), the use of other peripherals, such as a GPS receiver, the impact of the use of the Wi-Fi interface or the employed method to encode and forward the data that are collected from the sensors.

Analytical and empirical evaluation of the impact of Gaussian noise on the modulations employed by Bluetooth Enhanced Data Rates

Bluetooth (BT) is a leading technology for the deployment of wireless Personal Area Networks and Body Area Networks. Versions 2.0 and 2.1 of the standard, which are massively implemented in commercial devices, improve the throughput of the BT technology by enabling the so-called Enhanced Data Rates (EDR). EDRs are achieved by utilizing new modulation techniques (π/4-DQPSK and 8-DPSK), apart from the typical Gaussian Frequency Shift Keying modulation supported by previous versions of BT. This manuscript presents and validates a model to characterize the impact of white noise on the performance of these modulations. The validation is systematically accomplished in a testbed with actual BT interfaces and a calibrated white noise generator.

Prototyping of a remote monitoring system for a medical Personal Area Network using Python

This paper presents a prototype developed in Python of a pervasive mobile health system aimed at monitoring a patient in indoor and outdoor environments continuously. The system is based on a Bluetooth PAN (Personal Area Network), worn by the patient, whose master node, a smartphone, collects information about patients location and health status and detects emergency situations. These data are sent to a central server through Wi-Fi or GPRS/UMTS, which allows physicians to get access to patient data and configure the PAN sensors remotely using a conventional web browser.

A Smart Phone-based Personal Area Network for Remote Monitoring of Biosignals

This paper presents a system whose purpose is to monitor a patient continuously from indoor or outdoor environments. The system is based on a Bluetooth PAN, carried by the patient, whose central node, a smart phone, compiles information about patient’s location and health status. These data are encrypted to be sent to a server through Wifi or GPRS/UMTS. The system provides facilities to access to patient’s data, even from a smart phone by a J2ME application. It also allows to configure remotely the threshold values used to detect emergency situations.

Modeling of the transmission delay in bluetooth piconets under serial port profile

Bluetooth is a key connectivity technology for the deployment of wireless Personal Area Networks as far as it is the most popular low power communication feature incorporated in devices such as laptops or smartphones. This paper proposes an analytical model to predict the delay of the transmissions in Bluetooth piconets employing Serial Port Profile (SPP), which is massively implemented by Bluetoothenabled equipments. The characterization includes the impact of the overhead and the segmentation imposed by the different protocols involved in the transmission as well as the delay provoked by the polling process that is executed to regulate the activity of the different slaves in the piconet. The model has been empirically evaluated and tested in actual Bluetooth piconets.

Development and evaluation of a python telecare system based on a bluetooth body area network

This paper presents a prototype of a telemonitoring system, based on a BAN (Body Area Network) that is integrated by a Bluetooth (BT) pulse oximeter, a GPS (Global Positioning System) unit, and a smartphone. The smartphone is the hardware platform for running a Python software that manages the Bluetooth piconet formed by the sensors. Thus the smartphone forwards the data received from the Bluetooth devices, encoded into JSON (JavaScript Object Notation), to a central server. This server provides universal access to the information of the patients location and health status through a web application based on AJAX (Asynchronous JavaScript and XML) technology. Additionally, for the described prototype, the study presents some performance analyses about several topics that are of great interest for the applicability of the prototype: (i) the technique used to forward the patients location and health status, (ii) the power consumption of the smartphone (which is compared with the measurements of an equivalent software developed for Java Micro Edition platform), and (iii) the web browser compatibility of the web application developed for the control and monitoring of the patients.

An analytical model for estimating the delay in Bluetooth communications with serial port profile

Bluetooth is currently a major technology for the deployment of wireless short range communications. This paper presents an analytical model to compute the delay of Bluetooth transmissions with Serial Port Profile (SPP), which is nowadays widely utilized by commercial Bluetooth-enabled devices. In particular, the proposed equations permit to estimate the packet delay in ideal transmission conditions (when no retransmission occurs) and also when environmental noise induces losses and consequently there exist a certain probability that a packet has to be retransmitted. The model takes into consideration the overhead and segmentation introduced by the protocols involved in the transmission as well as the extra delay introduced by the retransmissions. The model has been empirically validated through the measurements of Bluetooth connections in an actual test-bed.

Analysis of Bluetooth transmission delay in personal area networks

Bluetooth is by far the most employed technology to develop practical applications of Wireless Personal Area Networks (WPAN). This paper studies the performance of Bluetooth transmissions that make use of the Bluetooth PAN (Personal Area Network) profile. In particular, the study offers an analytical model that defines the optimal bound for the end-to-end data delay. The proposed dasiadelay budgetpsila takes into account the overhead and segmentation provoked by the protocols involved in the transmission of user data. The model is empirically validated by comparing its results with those obtained through the measurements of actual Bluetooh connections.