In the past few years, several satisfying various objectives and designs of reconfigurable integrated microwave filter and antenna have been proposed for wireless communication systems. Several designs are new concepts and techniques, whereas others are inspired from previous works. The improvement concepts of these designs can be reviewed from this compilation of studies. This paper begins with an explanation of the reconfigurable filter, reconfigurable antenna and reconfigurable integrated microwave filter and antenna, followed by discussion on several designs in terms of size, measurement, performance and technology used. Among various designs, reconfigurable on planar structures are extensively used because of their simple design procedures and easy to tune on the desired frequency, bandwidth and attenuation. Most of the existing studies are focusing tunable on single element, i.e. either on filter or antenna side; however, it limits the tunable range and flexibility of the filtering antenna response. An alternative design of filtering antenna can be suggested to produce reconfigurable tuning capabilities on both microwave filter and antenna to produce overall good performance for multifunction operation in RF/microwave applications.
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