Abstract: A reconfigurable, dual-band, MIMO antenna apparatus, a planar MIMO antenna system utilizing the antenna apparatus, and a method of transmitting and receiving a signal by the antenna apparatus are provided. The apparatus includes a dielectric planar substrate, a first element, a second element, two varactor diodes per element, and a microstrip feed-line. The first element and the second element each have slotted concentric annular rings. The second element is separated on the dielectric planar substrate from the first element, but is coplanar on the dielectric planar substrate with the first element. The two varactor diodes are placed in series with biasing circuitry, the biasing circuitry including RF chokes and current-limiting resistors. The microstrip feed-line feeds both antenna elements. The dual-band antenna elements can each be independently and concurrently tunable to two signal frequencies bands.

Abstract: An antenna system and a method for fabricating an antenna system are disclosed. The antenna system includes a substrate having a top side and a bottom side, a single straight microstrip line on the top side of the substrate, a microstrip power divider (PD) on the top side of the substrate, and a ground plane on the bottom side. An input end of the single straight microstrip line is adjacent and vertical to a first edge of the substrate, and an output end of the single straight microstrip line is open. An input end of the microstrip PD is adjacent and vertical to a second edge of the substrate, and eight output ends of the microstrip PD are open. The first edge is parallel to the second edge. Further, three concentric square slots are etched on the ground plane.

Abstract: A miniaturized folded slot-based multiple-input-multiple-output (MIMO) antenna operating in the ultra high frequency (UHF) band for use in CubeSats. The MIMO antenna includes a circuit board having a front side and a back side separated by a dielectric material, a metallic coating covering the front side where the metallic coating is folded over a first edge and covers a first portion of the back side and is folded over a second edge and covers the second portion of the back side. A first meandering slot line is configured as a first antenna and a second meandering slot line is configured as a second antenna; a first metallic feed horn and a second metallic feed horn feed the first antenna and the second antenna, respectively. The antennas include a plurality of capacitors to tune a first resonance frequency of the first antenna and a second resonance frequency of the second antenna.

Abstract: A frequency reconfigurable miniaturized folded slot-based antenna for use with Internet of Things (IoT) devices. The antenna resonates at a lower band in the sub GHz range, and in an upper band at a low GHz range of 1 to 2 GHz. A front and a back side of a dielectric circuit board of the antenna includes a first metallic layer and a second metallic layer, respectively. Each metallic layer includes a meandering slot having a first and second plurality of connected legs, including at least a first leg, a center leg, and a last leg, respectively, where the first leg and the last leg wrap around the dielectric circuit board from the first metallic layer to the second metallic layer. The first metallic layer includes a varactor diode, a first choke and a second choke, and an open-ended microstrip transmission line for receiving signals from a feed line.

Abstract: An antenna system, an apparatus, and a method for configuring an antenna system are provided. The antenna system includes a dielectric substrate. The dielectric substrate has a top surface and a bottom surface. The antenna system also includes a first planar inverted-F antenna (PIFA) radiating element and a second PIFA radiating element disposed on the top surface of the dielectric substrate, each of the PIFA radiating elements having a F-head portion. The antenna system also includes at least two defected ground structures (DGSs) disposed on the bottom surface of the dielectric substrate and configured to provide isolation between the first and the second PIFA radiating element. Each DGS includes a varactor diode. The antenna system also includes a bias circuit corresponding to each of the at least two DGSs.

Abstract: Aspects of the disclosure provide an antenna system. The antenna system can include a dielectric substrate that has a top surface and a bottom surface covered by a ground plane, and four identical antenna elements symmetrically distributed on each corner of the bottom surface. Each antenna element can have a concentric-pentagonal-slot-based structure that is etched out of the ground plane, and includes an outer pentagonal slot and an inner pentagonal slot. Each side of the outer pentagonal slot can be parallel with a corresponding side of the inner pentagonal slot.

Abstract: An antenna system can include a dielectric substrate having a top surface and a bottom surface that is covered by a ground plane. Four identical antenna elements can be disposed on the bottom surface. Each antenna element can be formed by a pentagonal slot that is etched out of the ground plane. The four antenna elements are positioned symmetrically such that a layout of the four antenna elements has left-right symmetry and top-bottom symmetry. The dielectric substrate can be rectangular, and each pentagonal slot can have a side that is parallel with a longer edge of the dielectric substrate without a center of the pentagonal slots positioned between the side and the longer edge. The antenna system can further include a varactor diode for each of the four antenna elements. A capacitance of the varactor diode is loaded across the respective pentagonal slot.

Abstract: A dielectric substrate for a configurable antenna has an upper surface and an opposing lower surface. An upper conductor patch is disposed on the upper surface of the substrate and a lower conductor patch is disposed on the lower surface of the substrate. A sensing antenna is formed in the upper conductor patch. An upper set of slot antennas is formed in the upper conductor patch and a lower set of slot antennas is formed in the lower conductor patch. Each of the slot antennas is loaded with a variable reactance component.

Abstract: A low profile, 4-element, slot-based, frequency reconfigurable MIMO antenna for cognitive radio (CR) platforms for cellular communication front ends. The antenna is on a board having a top layer substrate and a bottom layer ground plane. The bottom layer ground plane contains four antenna elements, each antenna element having a circular slot and an annular slot spaced outwardly from and extending circumferentially around the circular slot. The bottom layer contains a microstrip feed-line for each antenna element. Varactor diodes on the top layer span the width of each annular slot to tune the resonance frequency over a wide operation band. The antenna covers a wide frequency band from 1800 MHz to 2450 MHz and supports several well-known wireless standards bands, including GSM1800, LTE, UMTS and WLAN, as well as many others.

Abstract: Aspects of the disclosure provide an antenna system. The antenna system can include a dielectric substrate that has a top surface and a bottom surface covered by a ground plane, and four identical antenna elements symmetrically distributed on each corner of the bottom surface. Each antenna element can have a concentric-pentagonal-slot-based structure that is etched out of the ground plane, and includes an outer pentagonal slot and an inner pentagonal slot. Each side of the outer pentagonal slot can be parallel with a corresponding side of the inner pentagonal slot.

Abstract: An antenna system, an apparatus, and a method for configuring an antenna system are provided. The antenna system includes a dielectric substrate. The dielectric substrate has a top surface and a bottom surface. The antenna system also includes a first planar inverted-F antenna (PIFA) radiating element and a second PIFA radiating element disposed on the top surface of the dielectric substrate, each of the PIFA radiating elements having a F-head portion. The antenna system also includes at least two defected ground structures (DGSs) disposed on the bottom surface of the dielectric substrate and configured to provide isolation between the first and the second PIFA radiating element. Each DGS includes a varactor diode. The antenna system also includes a bias circuit corresponding to each of the at least two DGSs.

Abstract: A dielectric substrate for a configurable antenna has an upper surface and an opposing lower surface. An upper conductor patch is disposed on the upper surface of the substrate and a lower conductor patch is disposed on the lower surface of the substrate. A sensing antenna is formed in the upper conductor patch. An upper set of slot antennas is formed in the upper conductor patch and a lower set of slot antennas is formed in the lower conductor patch. Each of the slot antennas is loaded with a variable reactance component.

Abstract: A compact, low profile integrated antenna design covering both 4G and 5G applications with good performance and that fits in handheld mobile terminals. The antenna design is a PIFA-based MIMO antenna system for 4G standards integrated with a planar connected array (PCA) for 5G bands. The antenna is fabricated on a two-layer printed circuit board (PCB) accommodating four antenna elements (3, 4, 5 and 6) along with a planar connected array (9) on a top layer, and a plurality of parallel slots (12) forming a defected ground structure in a bottom layer. The integrated antenna has approximately a typical smart phone backplane size. The plurality of parallel slots behave as a defected ground structure (DGS) for isolation enhancement within the MIMO antenna system band at 2.1 GHz and as a radiator (PCA) for 5G applications at 12.5 GHz.

Abstract: A low profile, 4-element, slot-based, frequency reconfigurable MIMO antenna for cognitive radio (CR) platforms for cellular communication front ends. The antenna is on a board having a top layer substrate and a bottom layer ground plane. The bottom layer ground plane contains four antenna elements, each antenna element having a circular slot and an annular slot spaced outwardly from and extending circumferentially around the circular slot. The bottom layer contains a microstrip feed-line for each antenna element. Varactor diodes on the top layer span the width of each annular slot to tune the resonance frequency over a wide operation band. The antenna covers a wide frequency band from 1800 MHz to 2450 MHz and supports several well-known wireless standards bands, including GSM1800, LTE, UMTS and WLAN, as well as many others.

Abstract: The wide band frequency agile MIMO antenna is a 4-element, reconfigurable multi-input multi-output (MIMO) antenna system. Frequency agility in the design is achieved using varactor diodes tuned for various capacitance loadings. The MIMO antennas operate over a wide band, covering several well-known wireless standards between 1610-2710 MHz. The present design is simple in structure with low profile antenna elements. The design is prototyped on commercial plastic material with board dimensions 60×100×0.8 mm3 and is highly suitable to be used in frequency reconfigurable and cognitive radio based wireless handheld devices.

Abstract: The wide band frequency agile MIMO antenna is a 4-element, reconfigurable multi-input multi-output (MIMO) antenna system. Frequency agility in the design is achieved using varactor diodes tuned for various capacitance loadings. The MIMO antennas operate over a wide band, covering several well-known wireless standards between 1610-2710 MHz. The present design is simple in structure with low profile antenna elements. The design is prototyped on commercial plastic material with board dimensions 60×100×0.8 mm3 and is highly suitable to be used in frequency reconfigurable and cognitive radio based wireless handheld devices.

Abstract: The cognitive radio antenna assembly includes two boards, a main board that has an ultra-wideband antenna (UWB) and also serves as a ground plane for the reconfigurable antenna, and an elevated MIMO board having two planar inverted-F antennas (PIFAs) that are reconfigurable to selectively operate on different frequency bands. Each PIFA has a radiating patch having a slot bridged by PIN diodes and DC blocking capacitors on opposite sides of the slot. The resonant frequency of each PIFA is controlled by which diodes are switched on and off. The PIFA antennas are shorted to the ground plane the (UWB antenna) on the main board by shorting walls. The PIFA antennas are capable of resonating from the 700 MHz band through 3000 MHz, while the UWB senses the spectrum over the entire bandwidth. The antenna assembly is compact, being suitable for cellular phone and wireless applications in 4G wireless standards.

Abstract: The cognitive radio antenna assembly includes two boards, a main board that has an ultra-wideband antenna (UWB) and also serves as a ground plane for the reconfigurable antenna, and an elevated MIMO board having two planar inverted-F antennas (PIFAs) that are reconfigurable to selectively operate on different frequency bands. Each PIFA has a radiating patch having a slot bridged by PIN diodes and DC blocking capacitors on opposite sides of the slot. The resonant frequency of each PIFA is controlled by which diodes are switched on and off. The PIFA antennas are shorted to the ground plane the (UWB antenna) on the main board by shorting walls. The PIFA antennas are capable of resonating from the 700 MHz band through 3000 MHz, while the UWB senses the spectrum over the entire bandwidth. The antenna assembly is compact, being suitable for cellular phone and wireless applications in 4G wireless standards.

Abstract: The reconfigurable MIMO and sensing antenna system combines a 2-element reconfigurable MIMO antenna system with a UWB element. The complete setup is suitable for CR platforms that require sensing UWB band availability. The design is planar in structure and includes a pair of PIFAs disposed on a dielectric substrate top surface. The UWB sensing element is disposed on the dielectric substrate bottom surface. An F-head portion of each PIFA has two arms extending to a longer peripheral edge of the substrate. An F-tail portion of each PIFA extends from the substrate's shorter peripheral edge. The two PIFAs are mirror images of each other. For each PIFA, three diode circuits include a PIN diode in combination with a varactor diode connected to and extending away from the F-tail portion of the PIFA, thereby creating separate radiating branches of the PIFA.

Abstract: The four element reconfigurable MIMO antenna system includes four conducting PIFA elements disposed on a top surface of a rectangular dielectric substrate. For each PIFA, an F-head portion of the PIFA defines two arms extending to a long peripheral edge of the substrate. An F-tail portion of the PIFA extends from a short peripheral edge of the substrate. A first PIFA and a second PIFA are mirror images of each other, and a third PIFA and a fourth PIFA are mirror images of each other. A meander pattern of conducting material extends from a bottom region of the F-tail portion of the PIFAs. For each PIFA, PIN/varactor diode bias circuits are disposed on the substrate's top surface, connecting to and extending away from a unique location on the F-tail portion of the PIFA, thereby creating separate radiating branches of the PIFA to achieve reconfigurability.