PerPos: A Translucent Positioning Middleware Supporting Adaptation of Internal Positioning Processes

Abstract

Abstract.A positioning middleware benefits the development of location aware applications. Traditionally, positioning middleware provides position transparency in the sense that it hides low-level details. However, many applications require access to specific details of the usually hidden positioning process. To address this problem this paper proposes a positioning middleware named PerPos that is translucent and adaptable, i.e., it supports both high-and low-level interaction. The PerPos middleware provides translucency with respect to the positioning process and allows programmatic definition of application specific features that can be applied to the internal position processing of the middleware. To evaluate these capabilities we extend the internal position processing of the middleware with functionality supporting probabilistic position tracking and strategies for minimization of the energy consumption. The result of the evaluation is that using only the proposed capabilities we can, in a structured manner, extend the internal positioning processing.

Sensing and Classifying Impairments of GPS Reception on Mobile Devices

“…The latter can be achieved since identifying current impairment sources can inform the receiver which satellites' ranging data to trust: GPS receivers can ignore ranging information from individual satellites which are believed to be distorted or currently received only indirectly; while such selection has been shown to potentially improve GPS accuracy [11], knowing the current user environment is crucial for picking proper selection criteria: E.g., in open sky environments stronger signals usually provide preciser ranging information, whereas in indoor environments the contrary can hold, when the strongest signals are likely to be signal reflections, reaching the user through windows, but only indirectly and thus yielding large ranging distortations [8]. Furthermore, providing application developers with access to the classifications is an example of benefitial seamfull design for developers [14]: E.g., in a positioning middleware, which is designed following a seamfull design approach to provide translucency w.r.t. the positioning process, the classifications could be used as an input to adapt application logic.…”

“…This concept is motivated foremost by the potential of information about GPS impairments and respective sources to improve GPS positioning quality and quality awareness: Both through GPS receiver algorithms, middleware [14] and application systems, utilizing such information, but also via informing the user directly via on-phone applications about current impairments, increasing his understanding of the position quality and help answering questions, such as "What is impacting my GPS positioning accuracy?" and "Can I improve GPS performance by changing my grip style or placement?"…”

On Architectural Qualities and Tactics for Mobile Sensing

“…If a degraded service is available, application logic can limit actions and user interfaces to make users aware of the degradation to, i.e., take correcting actions, and to build awareness of service limitations. Examples: Lemelson et al [24] propose methods to estimate the service degradation level for indoor positioning, and Langdal et al [22] present a middleware for handling quality adaptation for degraded services.…”

Indoor Pedestrian Navigation Based on Hybrid Route Planning and Location Modeling

“…Moreover, different communication protocols and data formats exist for different devices of the same type. Positioning middleware aims to shield application developers from the heterogeneity of positioning technologies, and to provide computed positioning and related functionalities high accuracy [5], [14], [20], [25], [27]. Furthermore, the Positioning Middleware often provides statistical methods for improving positioning in navigation and other tracking applications [14], [20], [25], [27], [29].…”