Patent ID: 8072283

Claim:
A method of modulating a base band signal for provision to at least one power amplifier comprising the steps of: receiving a base band signal provided as two Cartesian signals, separately mapping signal samples of each received Cartesian signal for forming two intermediary signals, where each sample of both Cartesian signals has been sampled using a common sampling interval, and is mapped to a corresponding intermediary signal section having one of a limited number of signal levels, said signal levels including only two non-zero levels that are separated from and provided symmetrically around zero, mapping each intermediary signal section of a corresponding intermediary signal to a segment of a corresponding pulse train, where said segment covers said sampling interval, said mapping being performed through providing a positive pulse in one half of the segment if the corresponding signal section has a positive signal level or a positive pulse in another half of the segment if the corresponding signal section has a negative signal level, forming a train of pulses made up of the pulse train segments for each intermediary signal, delaying the pulses of one of the trains in relation to the other train, and combining the two trains for provision to at least one power amplifier.