Abstract: A communication circuit may include a first pair of digital-to-analog converters (DACs) coupled to an input of a first mixer and configured to generate first baseband signals. The communication circuit may further include a second pair of DACs coupled to an input of a second mixer and configured to generate second baseband signals. The second baseband signals may be shifted in phase relative to the first baseband signals.

Abstract: A communication circuit may include a first pair of digital-to-analog converters (DACs) coupled to an input of a first mixer and configured to generate first baseband signals. The communication circuit may further include a second pair of DACs coupled to an input of a second mixer and configured to generate second baseband signals. The second baseband signals may be shifted in phase relative to the first baseband signals.

Abstract: A system includes: a baseband phase generator configured to receive differential in-phase (I) and quadrature (Q) signals and configured to output N phase-shifted baseband signals, wherein N is greater than 4, further wherein the baseband phase generator comprises a plurality of notch filters configured to receive the I and Q signals; and an upconverter configured to receive the phase-shifted baseband signals, to perform mixing on the phase-shifted baseband signals, and to output a differential upconverted signal.

Abstract: A system includes: a baseband phase generator configured to receive differential in-phase (I) and quadrature (Q) signals and configured to output N phase-shifted baseband signals, wherein N is greater than 4, further wherein the baseband phase generator comprises a plurality of notch filters configured to receive the I and Q signals; and an upconverter configured to receive the phase-shifted baseband signals, to perform mixing on the phase-shifted baseband signals, and to output a differential upconverted signal.

Abstract: Methods and apparatuses are presented for harmonic reject upconverting a baseband signal using at least one quadrature passive upconversion mixer. In some embodiments, an apparatus may include a first quadrature passive mixer configured to receive a first baseband input and a first LO input, and a second quadrature passive mixer configured to receive a second baseband input and a second LO input. A first output of said first passive mixer may be directly connected to a first output of said second passive mixer and together coupled to a first amplifier input. A second output of said first passive mixer may be directly connected to a second output of said second passive mixer and together coupled to a second amplifier input. The transmitter may be configured to output an upconverted signal with at least one rejected harmonic spurious mixing product based on the first and second amplifier inputs.

Abstract: Methods and apparatuses are presented for harmonic reject upconverting a baseband signal using at least one quadrature passive upconversion mixer. In some embodiments, an apparatus may include a first quadrature passive mixer configured to receive a first baseband input and a first LO input, and a second quadrature passive mixer configured to receive a second baseband input and a second LO input. A first output of said first passive mixer may be directly connected to a first output of said second passive mixer and together coupled to a first amplifier input. A second output of said first passive mixer may be directly connected to a second output of said second passive mixer and together coupled to a second amplifier input. The transmitter may be configured to output an upconverted signal with at least one rejected harmonic spurious mixing product based on the first and second amplifier inputs.

Abstract: The transmission path of a communication device includes, in part, N upconverters each of which receives M phases of a signal to be transmitted. Each upconverter further receives one of N sets of phases of a LO signal. Each of the N sets includes M phases of the LO signal. The communication device further includes at least one combiner, and N amplifiers each responsive to a different one of the N upconverters to generate N amplified signals. The combiner combines the N amplified signals to generate an output signal. By selecting the gain of one of the amplifiers to be different than the gain of the remaining amplifiers, the undesired harmonics of the signal to be transmitted, caused by non-linearity of the amplifiers, is reduced. Each upconverter optionally includes a multitude of upconverters whose outputs are combined to further reduce the spurious harmonic upconversion products and the counter-intermodulation distortion (IM3).

Abstract: The transmission path of a communication device includes, in part, N upconverters each of which receives M phases of a signal to be transmitted. Each upconverter further receives one of N sets of phases of a LO signal. Each of the N sets includes M phases of the LO signal. The communication device further includes at least one combiner, and N amplifiers each responsive to a different one of the N upconverters to generate N amplified signals. The combiner combines the N amplified signals to generate an output signal. By selecting the gain of one of the amplifiers to be different than the gain of the remaining amplifiers, the undesired harmonics of the signal to be transmitted, caused by non-linearity of the amplifiers, is reduced. Each upconverter optionally includes a multitude of upconverters whose outputs are combined to further reduce the spurious harmonic upconversion products and the counter-intermodulation distortion (IM3).