Dual-linear polarised antenna module with enhanced transmit-receive isolation

A dual-linear polarised antenna module for frequency-domain duplex base-station antenna arrays is described. Designed for the frequency bands 1.92-1.98 and 2.11-2.17 GHz, the antenna radiators are matched to -17 dB return loss. The antenna modules have been arranged in a dual-linear polarised array. Inter-element coupling has been reduced by insertion of conducting walls. The module features separate feeds for transmit and receive signals, and realises an isolation of 20 dB in the described array arrangement. The balanced-fed radiator elements are surface-mounted onto a printed circuit board, which serves as a groundplane and provides the balun structures. Radiators are made of three-dimensional parts suited for injection moulding. Prototypes built using a stereolithography process verify expected performance by measurements