Multiband and multicarrier operations in HSDPA

Multicarrier operation offers significant gains by bandwidth extension as well as by its inherent ability to exploit diversity while transmitting on different adjacent carrier frequencies. A natural enhancement of this technique is multiband operation, since at different non-adjacent bands even more diverse radio conditions are to be found. Furthermore, since penetration of Third Generation (3G)-capable mobile devices is increasing, operators may consider to reuse 900 MHz band used by Global System for Mobile Communications (GSM) to enhance experience of growing 3G users´ community. It is expected that the usage of 900 MHz band will not only expand bandwidth available for transmission but it will also bring significant gains especially for cell edge users, who often suffer from heavy interference conditions. This paper describes effects of utilizing available bands other than 2100 MHz in a multicarrier operation mode.