Abstract: In the present technique of duplex local oscillator technique provided, a radio frequency local oscillator frequency and a duplex local oscillator frequency at a selected timeslot are assessed (516, 520) to provide a radio frequency local oscillator signal (518) and a duplex local oscillator signal (522), respectively. The duplex local oscillator signal and the radio frequency local oscillator signal are mixed (524) to provide a converted radio frequency local oscillator signal, which is then provided (526) for output.

Abstract: A block edge detector (310) determines (510) whether a wireless communication transmission with a first modulation having excess spectral emissions will be transmitted at a frequency on a block edge (120). In response, a modulator selector (320) changes (530) the wireless communication transmission to a second modulation with lessened spectral emissions. Preferably, the second modulator (340) is operably coupled to an alternative lookup table (360) wherein phase trajectory entries likely to cause excess spectral emissions such as spurious emissions are smoothed. The entries may be smoothed by filtering, non-linear extrapolation, and/or linear extrapolation. Alternatively, the second modulator (340) uses an alternative lookup table (360) that is a GMSK modulator with BT less than 0.3.