Towards suppression of all harmonics in a polyphase multipath transmitter

This work proposes a direct conversion transmitter architecture intended for cognitive radio applications. The architecture is based on the poly-phase multipath technique, which has been shown to cancel out many of the harmonics, sidebands and nonlinearity contributions of a power up converter using a large number of signal paths. This work proposes a design only using 8 paths which is able to achieve <;-40dBc harmonic suppression for all harmonics, including the dominant 7^th and 9^th harmonic. This is done with a combination of duty cycle control of the Local Oscillator (LO) waveform and tunable filtering with only a first order roll-off.