A local oscillator (LO) signal generator that has a reference phase-locked loop (PLL), a receiver LO PLL and a transmitter LO PLL. A reference PLL is coupled to receive a reference clock input and to generate a reference PLL signal at its output, which then drives a receiver PLL and a transmitter PLL. The receiver PLL is coupled to receive the reference PLL signal and to use the reference PLL signal as its reference input to generate a receiver LO signal at its output. The transmitter PLL is coupled to receive the reference PLL signal and to use the reference PLL signal as its reference input to generate a transmitter LO signal at its output.