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A fast frequency-hopping six-band local oscillator signal generator is described in this paper. Targeted for a Wi-Media ultra-wideband radio transceiver, it offers operation in mandatory band group 1 and in extensional band group 3. The circuit entity consists of three parallel phase-locked loops (PLLs), each including two voltage-controlled oscillators, one per band group, and a signal multiplexer for fast frequency selection. A broadband poly-phase RC filter is used for in-phase/quadrature generation. Furthermore, the synthesizer generates the clock signal for analog-to-digital converters by mixing the signals from the first and third PLL. The circuit was fabricated in a 0.13- mum CMOS process and it consumes 32 mA from a 1.2-V supply. It achieves 2-ns frequency settling time with a 3-MHz hopping rate.