Growth of mobile users is projected to reach 6 billion by 2013, with 80% of users in the developing world where the mobile phone is their primary communication and computing device. At the same time, sales of energy-intensive Smart Phones have grown 15% last year with all mobile phones to be Smart by 2015. The increased consumption means an average replacement rate of 18 months, accounting for ...

A novel and broadband spiral chip antenna is presented in this paper. The size of the proposed antenna is 20× 3.2 × 8mm and is suitable to be embedded in a mobile phone as an internal antenna. Also, this antenna is designed to be installed at the newest mobile handset whose size is 40 × 93mm. The minimization of this antenna was realized by using spiral line structure on FR-4 of dielectric perm...

Using data on mobile phone handset sales from a single retail store, we examine the impact of different retail responsibility designations and vertical contracts on seller service provision, firm profitability, and social welfare. During our sample, this store switched from retailer-managed retailing with linear pricing contracts to manufacturermanaged retailing with revenue sharing. We estimat...

This paper introduces a novel scheme for mobile handset authentication and authorization in a geographically wide spread area spanning the coverage of multiple network service providers. The existing set up involves the exchange of a large number of control signals between the foreign network and mobile node, and between foreign network and home network for authentication and authorization, whi...

Automatic location identifications are required for emergency calls in Japan and many other countries. However, giving a reliable position promptly is a problem in places where the global positioning system (GPS) signal is extremely weak. We propose an acquisition scheme for assisted GPS (AGPS) architecture based on a timingsynchronized mobile network. System errors as well as code uncertainty ...

This study models the intention to use novel mobile peer-to-peer communications and content sharing services and determine their adoption potential. A sample of 155 Finnish customers with an advanced mobile handset was collected and analyzed. The Theory of Planned Behavior conceptual model for measuring behavioral intention was applied in the context of novel mobile services. The model was esti...

Despite the advances in battery technologies, mobile phones still suffer from severe energy limitations. Modern handsets are rich devices that can support multitasking thanks to their high processing power and provide a wide range of resources such as sensors and network interfaces with different energy demands. There have been multiple attempts to characterise those energy demands; both to sav...

Abstracr We construct simal constellations for differential transmission with multiple basestation antennas. The signals are derived using the theory of fixed-point-free groups and are especially suitable for mobile cellular applications because they do not require the handset to have more than one antenna or to know the time-varying propagation environment. Yet we achieve full transmitter dive...