Novel Phase Difference Control Between Output Signals Using Fractional-N PLL Synthesizers by Cyclic Shift of Control Data

This paper reports novel phase difference control of output signals by use of multiple fractional-N PLL (F-PLL) synthesizers. In proposed F-PLL synthesizers, reset timing of fractional modulators is controlled to realize cyclic shift of control data for frequency dividers, which generates phase difference of output signals. This technique makes highly accurate phase difference control possible, and is demonstrated with L-band F-PLL synthesizers.