IMPROVED MIXERS WITH A PLURALITY OF LOCAL OSCILLATORS AND SYSTEMS BASED THEREON

摘要

Apparatus (40) for processing an input signal (SRF(t)) with a carrier frequency (omega RF)defining a desired band and at least a sideband being defined by a sideband frequency (nomega LO) that is higher than the carrier frequency (omega RF). The apparatus (40) comprises a main input (50) for receiving said input signal(SRF(t))and a first standard mixer (41) having a first mixer input (44), a first local oscillator input (47), and a first mixer output (A). The first mixer input (44) is connected to the main input (50) and the first local oscillator input (47) is connected to a source that provides a first local oscillator signal (LO1) having a frequency (omEga LO). This frequency (omega LO) is close to or equal to the carrier frequency (omega RF). The first standard mixer (41) performs a multiplication of the input signal (SRF(t)) and the first local oscillator signal (LO1) to provide a first output signal (SA(t))at the first mixer output (A). The apparatus (40) further comprises a second mixer (42) with a second mixer input (45), a second local oscillator input (48), and a second mixer output (B). The second mixer input (45) is connected to the main input (50) and the second local oscillator input (48) is connected to a source that provides a second local oscillator signal (LO2) with the sideband frequency (nomega LO). The second mixer (42) performs a multiplication of the input signal (SRF(t)) and the second local oscillator signal (LO2) to provide a second output signal (SB(t)) at the second mixer output (B). There are means for superpositioning (51) the first output signal (SA(t)) and the second output signal (SB(t)). The first local oscillator signal (LO1) and the second local oscillator signal (LO2) are square-wave signals.