SUPPRESSION OF SPURIOUS HARMONICS GENERATED IN TX DRIVER AMPLIFIERS

摘要

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).

主权项

1. A communication device having a transmission path comprising:
N upconverters each receiving M phases of a baseband signal to be transmitted, each upconverter further receiving a different one of N sets of phases of a local oscillator (LO) signal, each of the N sets comprising M different phases of the LO signal; N amplifiers each responsive to a different one of the N upconverters to generate N amplified signals; and at least one combiner adapted to combine the N amplified signals to generate an output signal, wherein a frequency component falling at a multiple of a sum of a LO signal frequency and a baseband signal frequency, or a multiple of a difference between the LO signal frequency and the baseband signal frequency is substantially suppressed from the output signal by selecting a gain of at least a first one of the N amplifiers to be different from a gain of a remaining one of the N amplifiers, wherein N and M are integers greater than 1.