No abstract

The mobile radio systems beyond third generation (3G) will evolve in all-IP systems, integrating Internet and mobile systems advantages. BRAIN project is developing a system architecture which combines local coverage broadband radio access systems based in HIPERLAN/2 with several wider coverage mobile radio systems, enabling full coverage of seamless IP-based services for users in hot spot areas and on the move. End to end quality of service (QoS) provision is one of the mayor challenges in the design of such a system and must be supported by the application, network and wireless access layers. This paper proposes a QoS system architecture, including the terminal architecture, the IP based access network and the main characteristics of the enhancements to the air interface based in HIPERLAN/2 focusing on its wireless QoS support.

In street microcells, cochannel interference problem arises especially at the street intersections without base station site where interference level can go up very rapidly due to the possible line-of-sight interference. To guarantee contiguous service quality in the street crossings rather conservative reuse distances should be selected at the expense of lower system capacity. In this paper we show that at the street intersections a single interfering signal dominates suggesting that interference cancellation of the dominant interfering signal is a potential method to overcome the problem. Accordingly, we apply joint detection of the desired and dominant interfering signal in the GSM system and evaluate the potential advantage in the Manhattan microcell environment. The results indicate that this tecnique enables very low reuse distances in the future high capacity microcellular systems.

This paper proposes a novel symmetric superregenerative transceiver architecture for pulsed short-range communication. The proposed architecture is targeted for wireless applications where ultra low power consumption and data-rate in tens of megabits per second are needed over distances in the range of tens of centimeters. The transmitter and receiver are both based on super-regenerative principle and both functions in the transceiver utilize one mutual super-regenerative oscillator. Additionally, the transceiver architecture allows fast synchronization of transceivers thanks to the delayed reflection phenomenon which makes it possible to detect correct timing simultaneously at both ends of the system. Measurement results demonstrate the feasibility of the proposed principle.

The presented approach addresses the problem of query and persistent query (subscription) resolution, taking into consideration distribution across multi-domains, network infrastructure and content management. This approach is particularly suitable for information-centric and cloud computing applications based around a mobile-device infrastructure.