BLUETOOTH is currently being introduced into several market segments, like mobile phones, headsets, PC’s etc. Bluetooth operates in the ISM-band between 2.4 GHz and 2.48 GHz and uses 80 channels, with a channel spacing of 1 MHz. Bluetooth was orginally specified in such a way that the complete system, i.e. radio and baseband, could be integrated into a single CMOS integrated circuit. This resulted in a quite poor specification for the sensitivity (-70 dBm) and output power (0 dBm, Class II) [1], [2].

In practice, it now becomes clear that systems that just meet this specification show a quite poor quality, especially for indoor voice/audio applications. There fore, the newest generation of Bluetooth BiCMOS radios show a much improved performance, with a sensitivity better than -80 dBm and output power up to +4 dBm or higher.

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