A microstrip patch antenna structure is disclosed having increased bandwidth and reduced coupling while maintaining low profile capabilities. The structure includes a support member having an isolating recess in which an electromagnetically coupled patch pair of antenna elements is positioned, the upper element being substantially flush with the surface of the support member surrounding the recess. To enhance isolation of the elements, the recess walls and the support surface are preferably electrically conductive and connected to ground. Also preferably, the lower element is connected to a microstrip transmission line, coplanar with the lower element and suspended within an isolating channel through the support member. In one aspect of the invention, a transition means is interposed between the transmission line and a connector, which connects the support member to a transmitter/receiver, to permit relative rotation therebetween. The transition means can also include means for capacitively coupling the transmission line with the connector.
A patch antenna has: a driven patch fed with a high-frequency signal and radiates a high-frequency electromagnetic field from its one surface; a parasitic patch receives the high-frequency electromagnetic field from the driven patch at a first surface and reradiates the high-frequency electromagnetic field from a second surface; and a radome which protectively holds the driven patch and the parasitic patch inside of the radome; wherein the parasitic patch is held by the inner surface of the radome which contacts the second surface of the parasitic patch and by a holder which protrudes from the inner surface of the radome and covers a part of the first surface of the parasitic patch.
A rotatable microstrip patch antenna and an array antenna using the same is disclosed. A rotatable microstrip patch antenna, includes: a first substrate layer capable of being predetermined angle rotated toward a predetermined direction for inputting and outputting a transmitting/receiving signal; a second substrate layer arranged bottom of the first substrate layer with a predetermined distance space for transmitting and receiving signals to/from the first substrate layer; and a signal transferring unit for allowing a rotation of the first substrate layer and transferring the signals between the first substrate layer and the second substrate layer.
A circularly polarized antenna device in which a recess is formed in the bottom surface of a dielectric base, and in which a feeder circuit is formed on an area of the top surface of a feeder circuit board covered by the recess. A shield for the feeder circuit is provided inside the recess. A feeder electrode is formed on an outer peripheral side surface of the dielectric base so as to be separated from a radiation electrode. A feeder wiring pattern which connects the feeder circuit and the feeder electrode so that they are in electrical conduction is formed on the top surface of the feeder circuit board. Electrical power supplied to the feeder electrode from the feeder circuit through the feeder wiring pattern is transmitted to the radiation electrode by capacitive coupling. Since the feeder circuit and the shield are accommodated inside the recess of the dielectric base, it is possible to restrict the bulkiness of the circularly polarized antenna device, and, thus, to make it thin. The invention aims at making the circularly polarized antenna device thinner.
A phased array antenna having stacked-disc radiators embedded in dielectric media. The phased array antenna has a rectangular arrangement of unit cells that are disposed on a ground plane. A lower dielectric puck with a high dielectric constant is disposed on the ground plane. An excitable disc is disposed within the perimeter of and on top of the lower dielectric puck. An upper low dielectric constant dielectric puck that has a dielectric constant lower than that of the lower dielectric puck is disposed on the excitable disc. A parasitic disc is disposed within the perimeter of and on top of the upper dielectric puck. Dielectric filler material having a dielectric constant that is lower than that of the lower dielectric puck surrounds the dielectric pucks. A radome 18 is disposed on top of the parasitic disc and the unit cell. Two orthogonal pairs of excitation probes are coupled to the lower excitable disc. The polarization of the phased array antenna may be single linear polarization, dual linear polarization, or circular polarization depending on whether a single pair or two pairs of excitation probes are excited
A planar antenna for microwave applications includes a supporting structure that is made using standard LTCC (low temperature co-fired ceramics) multi-layer techniques and a polyimide tape containing an adhesive at one side which is adheringly attached to the supporting structure. The body of the supporting structure defines a transmission line substrate and several of the intermediate layers define a path for microwave energy to be coupled from the transmission line substrate to the antenna. The method includes adhering the tape to the supporting structure, cutting the tape to size, and baking the tape and supporting structure in an oven at about 180.degree. C. for about 4 hours to rigidify the tape. The obtained antenna is thus protected against substrate effects such as TM mode zero cut-off frequencies.
