| 主权项 |
1. An apparatus, comprising:
a first apparatus port configured to receive a first signal having a first frequency; a second apparatus port; a third apparatus port configured to output the first signal having the first frequency and to receive a second signal having a second frequency, wherein the second apparatus port is configured to output the second signal having the second frequency; first, second, third, and fourth passive devices, each having a corresponding first device port and a corresponding second device port, wherein the second device ports of the first and third passive devices are connected together with a first impedance matching device and the second device ports of the second and fourth passive devices are connected together with a second impedance matching device, a plurality of phase shifters each configured to provide a corresponding phase shift, wherein at least one of the phase shifters is configured to provide its corresponding phase shift in a first signal path between the first and third apparatus ports through the first passive device, wherein at least another of the phase shifters is configured to provide its corresponding phase shift in a second signal path between the first and third apparatus ports through the second passive device, wherein still another of the phase shifters is configured to provide its corresponding phase shift in a third signal path between the second and third apparatus ports through the third passive device, and wherein yet another of the phase shifters is configured to provide its corresponding phase shift in a fourth signal path between the second and third apparatus ports through the fourth passive device; wherein the phase shifts are selected to cancel one of an upper or lower intermodulation product between the first signal, and a third signal having a third frequency received at the third apparatus port. |
