Pekka Peltola

Indoor location based services challenges, requirements and usability of current solutions

Indoor Location Based Services (LBS), such as indoor navigation and tracking, still have to deal with both technical and non-technical challenges. For this reason, they have not yet found a prominent position in people’s everyday lives. Reliability and availability of indoor positioning technologies, the availability of up-to-date indoor maps, and privacy concerns associated with location data are some of the biggest challenges to their development. If these challenges were solved, or at least minimized, there would be more penetration into the user market. This paper studies the requirements of LBS applications, through a survey conducted by the authors, identifies the current challenges of indoor LBS, and reviews the available solutions that address the most important challenge, that of providing seamless indoor/outdoor positioning. The paper also looks at the potential of emerging solutions and the technologies that may help to handle this challenge.

Indoor positioning technology assessment using analytic hierarchy process for pedestrian navigation services

Indoor positioning is one of the biggest challenges of many Location Based Services (LBS), especially if the target users are pedestrians, who spend most of their time in roofed areas such as houses, offices, airports, shopping centres and in general indoors. Providing pedestrians with accurate, reliable, cheap, low power consuming and continuously available positional data inside the buildings (i.e. indoors) where GNSS signals are not usually available is difficult. Several positioning technologies can be applied as stand-alone indoor positioning technologies. They include Wireless Local Area Networks (WLAN), Bluetooth Low Energy (BLE), Ultra-Wideband (UWB), Radio Frequency Identification (RFID), Tactile Floor (TF), Ultra Sound (US) and High Sensitivity GNSS (HSGNSS). This paper evaluates the practicality and fitness-to-the-purpose of pedestrian navigation for these stand-alone positioning technologies to identify the best one for the purpose of indoor pedestrian navigation. In this regard, the most important criteria defining a suitable positioning service for pedestrian navigation are identified and prioritised. They include accuracy, availability, cost, power consumption and privacy. Each technology is evaluated according to each criterion using Analytic Hierarchy Process (AHP) and finally the combination of all weighted criteria and technologies are processed to identify the most suitable solution.

Overview of positioning technologies from fitness-to-purpose point of view

Even though Location Based Services (LBSs) are being more and more widely-used and this shows a promising future, there are still many challenges to deal with, such as privacy, reliability, accuracy, cost of service, power consumption and availability. There is still no single low-cost positioning technology which provides position of its users seamlessly indoors and outdoors with an acceptable level of accuracy and low power consumption. For this reason, fitness of positioning service to the purpose of LBS application is an important parameter to be considered when choosing the most suitable positioning technology for an LBS. This should be done for any LBS application, since each application may need different requirements. Some location-based applications, such as location-based advertisements or Location-Based Social Networking (LBSN), do not need very accurate positioning input data, while for some others, e.g. navigation and tracking services, highly-accurate positioning is essential. This paper evaluates different positioning technologies from fitness-to-purpose point of view for two different applications, public transport information and family/friend tracking.

Computer Forensic Analysis of Private Browsing Modes

This paper investigates the effectiveness of the private browsing modes built into four major Internet browsers. In examining the phenomenon of the private browsing modes built into four widely used Internet browsers, this paper aims to determine whether one can identify when a private browsing mode has been utilized by a suspect to perform a criminal or illegal act and to what extent the forensic examination of a computer can expose evidence of private browsing use.

Integrated Computer Forensics Investigation Process Model (ICFIPM) for Computer Crime Investigations

Contrary to traditional crimes for which there exists deep-rooted standards, procedures and models upon which courts of law can rely, there are no formal standards, procedures nor models for digital forensics to which courts can refer. Although there are already a number of various digital investigation process models, these tend to be ad-hoc procedures. In order for the case to prevail in the court of law, the processes followed to acquire digital evidence and terminology utilised must be thorough and generally accepted in the digital forensic community. The proposed novel process model is aimed at addressing both the practical requirements of digital forensic practitioners and the needs of courts for a formal computer investigation process model which can be used to process the digital evidence in a forensically sound manner. Moreover, unlike the existing models which focus on one aspect of process, the proposed model describes the entire lifecycle of a digital forensic investigation.

Particle filter for context sensitive indoor pedestrian navigation

Novel particle filter design combines foot mounted inertial (IMU), bluetooth low energy (BLE) and ultra-wideband (UWB) technologies along with map matching into a seamless integrated navigation system for indoors. The system was evaluated by 10 test walks along an 80m long indoor track including stairs and running. 95% of the time the average error for a particle was below 3.1 m with filter completion success rate of 90%. Furthermore, a system without UWB using only IMU, BLE and map matching achieved an average error for a particle to be below 3.6 m with filter completion success rate of 70%. The selected technologies and sensors are affordable and easily deployable. Inertial measurement units characteristics complement the disadvantages in the rf technologies and vice versa. The code for the rover can be implemented on a modern mobile device together with a foot mounted IMU.

Blind sub-Nyquist GNSS signal detection

A satellite navigation receiver traditionally searches for positioning signals using an acquisition procedure. In situations, in which the required information is only a binary decision whether at least one positioning signal is present or absent, the procedure represents an unnecessarily complex solution. This paper presents a different approach for the binary detection problem with significantly reduced computational complexity. The approach is based on a novel decision metric which is utilized to design two binary detectors. The first detector operates under the theoretical assumption of additive white Gaussian noise and is evaluated by means of Receiver Operating Characteristics. The second one considers also additional interferences and is suitable to operate in a real environment. Its performance is verified using a signal captured by a receiver front-end.

Towards Seamless Navigation

Seamless navigation using one single mobile device would ease navigation. This goal demands detection of context. That is the environment (outdoor, indoor, car, etc.) and behaviour (walk, run, climb, etc.) of the location and user. Each positioning technology (inertial, radio frequency, sound, etc.) has its inherent characteristics. If correctly designed, the navigation system uses multiple sensors and combines the best characteristics of the available sensors in an optimal way. Battery consumption and accuracy of the system meets the needs for all environments. The user would not be aware of how the device works so well all the time—a seamless navigation device. This chapter provides a review of the available sensors and methods that can be used to complement GNSS, in scenarios where GNSS is not enough for seamless navigation.

GNSS Trajectory Anomaly Detection Using Similarity Comparison Methods for Pedestrian Navigation

The urban setting is a challenging environment for GNSS receivers. Multipath and other anomalies typically increase the positioning error of the receiver. Moreover, the error estimate of the position is often unreliable. In this study, we detect GNSS trajectory anomalies by using similarity comparison methods between a pedestrian dead reckoning trajectory, recorded using a foot-mounted inertial measurement unit, and the corresponding GNSS trajectory. During a normal walk, the foot-mounted inertial dead reckoning setup is trustworthy up to a few tens of meters. Thus, the differing GNSS trajectory can be detected using form similarity comparison methods. Of the eight tested methods, the Hausdorff distance (HD) and the accumulated distance difference (ADD) give slightly more consistent detection results compared to the rest.

Location Based Services Analysis Through Analytical Hierarchical Processes: An e-Health-Based Case Study

In Location Based Services, there is often the need to find out which positioning technology is best fit to a certain target service and how to design a certain service or application according to users’ needs and various constraints. One solution to tackle such problems is to use tools from the Multi-Criteria Decision-Making theory. This chapter presents one of the MCDM approaches, namely the Analytical Hierarchical Processes, which can be applied in many scenarios and parts of LBS applications. After describing what AHP is and how it can be applied in the context of wireless localisation, a simplified example is given, based on location based services in the e-health area. The e-health area has been chosen here as one of areas highly relevant for the social well-being, where localisation is becoming of utmost importance. In this chapter, also the challenges in choosing the right wireless localisation technology to support various LBS and the possible open directions are emphasised, in such a way that the reader could further find an easy mapping of AHP to his/her own LBS-related questions.