Abstract :
Multiple wireless interfaces (GSM, Wi-Fi, Bluetooth, FM, and GPS receiver, etc.) are being integrated into mobile devices. WiMAX, an IEEE802.16-based wireless access technology recently included in the IMT-2000 set of standards by ITU-R, will soon be added. Obstacles remain to operating these collocated radios concurrently, including interference and hardware conflicts due to congested spectrum allocation and component sharing with radio integration. In this article we provide a tutorial overview of today´s solutions to enable concurrent operation of multiple collocated radios in IEEE 802.16- based wireless networks with a focus on perceived concurrency: a MAC coordination approach. We then present three general design principles - predictability, compressibility, and flexible scheduling - with examples of standard features. It is anticipated that the next-generation IEEE 802.16 standards will be enhanced with new features such as explicit service setup, asynchronous operation, and collocated coexistence-aware scheduling.
Keywords :
WiMax; access protocols; broadband networks; mobile radio; radio access networks; IEEE 802.16 network; MAC coordination approach; WiMax; component sharing; medium access control; mobile device; multiple wireless interface; perceived concurrency; radio integration; scheduling; spectrum allocation congestion; Concurrent computing; Digital signal processing; Hardware; Interference; Noise generators; Performance evaluation; Phase noise; Physical layer; Radio frequency; Receivers;