Design Of CMOS Mixer For Bluetooth Receiver

Integrated circuit has been developed rapidly along with the fast development of COMS technology. Radio frequency, intermediate frequency and baseband circuits are intend to be integrated on a single chip. Mixer is a key part of Bluetooth receiver system, which functions to move the frequency of RF signal in spectrogram. This paper designed a sampling mixer module in accordance with Bluetooth specification, which can be manufactured in deep sub-micrometer processes. Designed mixer module can be integrated with the digital baseband signal processing module on a single chip. Moreover, since sampling mixer is always affected by folded noise, the paper also designed on-chip digital decimation filter and its driver circuit of digital signal generation module, which greatly enlarge the possibility of design of single chip Bluetooth receiver.The mixer designed with TSMC 0.18um CMOS technology is simulated under simulation environment of Cadence Spectre, with the following results: RF frequency is 2.405GHz, LO frequency is 2.4GHz, gained IF frequency is 5MHz. The mixer has a noise figure of 26dB, 1-dB compression point of -8dbm, and IIP3 of 0dbm. Designed mixer, which is powered by 1.8v voltage, totally meets the technical needs of Bluetooth receiver. Simulation result indicates that designed mixer has advantage in linearity, and a relatively good noise figure due to the following on-chip digital decimation filter.