Method and apparatus for antenna radiation cross polar suppression

摘要

Cross-polar discrimination (XPD) of a dual orthogonal cross-polarized antenna is maximized via a cross-coupling network between base station MIMO branches prior to connection to the base station antenna. In one embodiment, a cross coupling network combines each MIMO branch signal with an attenuated phase reversed (phase shifted) copy of the other MIMO branch signal. The amount of attenuation for each branch is equivalent to the cross polar suppression required for each antenna array. The cross-coupling can be applied at different stages of signal processing within a base station.

主权项

1. A system, comprising:
a base station with two Multiple In-Multiple Out (MIMO) RF ports; and a cross-coupling network configured to vectorially combine power from each of the MIMO RF port to the other MIMO RF port, wherein the cross-coupling network comprises two input ports and two output ports, where a first input signal on one of the two input ports is split into two component signals having a variable power difference between the two component signals, wherein one of the two component signals receiving a variable phase delay to generate a first delayed component signal, where a second input signal on one of the two input ports is split into two component signals having a variable power difference between the two component signals, wherein one of the two component signals receiving a variable phase delay to generate a second delayed component signal, wherein an un-delayed component signal associated with the first input signal is combined with the second delayed component signal associated with the second input signal, wherein the un-delayed component signal associated with the second input signal is combined with the first delayed component signal associated with the first input signal.