Göran Malmgren

Overview and performance of HIPERLAN type 2-a standard for broadband wireless communications

At present, standards for broadband wireless multimedia communications in the 5 GHz band are being developed in Europe as well as in the US and Japan. HIPERLAN type 2 (H/2) is being specified by the ETSI BRAN (Broadband Radio Access Networks) project; the core parts of the specification were finalised at the end of 1999. Almost total harmonisation has been achieved between the standardization bodies in Europe and Japan, ETSI and ARIB, respectively. An overview of the H/2 standard is presented together with exemplary link and system performance results.

Automatic repeat request (ARQ) mechanism in HIPERLAN/2

A WLAN standard, called HIPERLAN/2 (H/2), is currently defined in the ETSI/BRAN project. The standard can provide wireless access to several fixed networks with high data rate (up to 54 Mbps) in 5 GHz frequency range. To guarantee robustness in various types of radio channels a selective repeat ARQ with partial bitmap SRPB has been adopted as an error control mode. The SRPB ARQ mechanism was selected due to efficient retransmissions and low overhead of ARQ acknowledgements. The dynamic assignment ARQ acknowledgement opportunities integrated in SRPB can reduce the delay of acknowledgements and enhance the throughput. In this paper we describe the SRPB ARQ mechanism in H/2 and show the simulated performance.

Beyond 3G radio access network reference architecture

Today a multitude of radio access technologies exist and are continuously evolved to support higher bit rates, lower delays, lower cost, etc. In addition, new radio access technologies are developed to complement those of today. When using services in this environment with multiple radio access technologies, end users expect mobility between the different radio access technologies to be seamless. Network operators, in addition, look for efficient resource usage of different radio access technologies and more cost efficient ways to deploy networks. This requires increased flexibility in the radio access network architecture compared with todays architectures. In this paper a beyond 3G radio access network reference architecture supporting these requirements is presented. The architecture allows for various implementations and considers new deployment concepts such as multi-hop radio networks, moving networks and personal area networks.