Mukherjee, Soumava

This paper presents a single-stage amplifier using substrate-integrated coaxial line (SICL) technology. It is implemented with a low-cost PCB technique at 23.35–24.05 GHz. The size of the proposed amplifier is 4.9λg×1.1λg where λg is the guided wavelength at the center frequency. In this circuit, a SICL-based bias-tee network is designed where the mounting pads are introduced for the integration of the components, such as transistor and capacitor. Next, with the help of de-embedding techniques, the input and output matching networks are designed in the SICL environment at 24 GHz. The proposed amplifier circuit exhibits 9.2 dB of peak gain with less than 1 dB of gain ripple and more than 10 dB of input/output return losses in the operating frequency band of 23.35–24.05 GHz. Moreover, the elementary blocks of the amplifier are presented in the circuit. Based on the appropriate modeling of the amplifier's elementary blocks, the simulated and measured results are in good agreement.

In this study, a novel and compact substrate integrated broadband Dielectric Resonator Antenna (DRA) excited by Substrate Integrated Coaxial Line (SICL) is presented. In comparison to the traditional non-planar DRA configuration, that requires mounting of a dielectric over the feed, the presented work provides a simple alternative by utilizing the same substrate of the SICL feed network making it planar. This eliminates the major challenge of a complex fabrication process in designing DRA. Two semi-circular rings fed by the top and middle layer of SICL feed line forms the resonating structure of the DRA, exhibiting a bandwidth of 550 MHz. The design procedure is shown to enhance the bandwidth to 1.3 GHz of the proposed antenna. The field distribution attained in the suggested Dielectric Resonator Antenna (DRA) has similarities to the HEM12δ mode of the standard cylindrical DRA. The proposed DRA achieves a broadside unidirectional beam with a gain of 5.5 dBi at 26 GHz.

This paper presents a novel technique to implement crossed dipole antenna fed by Substrate Integrated Coaxial Line (SICL) technology. The inherent advantage of out of phase surface current of the SICL transmission line is utilized efficiently to excite the two dipole antennas. The crossed dipole is implemented such as to obtain dual band response at 26 GHz and 28 GHz. Two ±45° inclined dipoles are printed on the top/bottom of the substrate and simultaneously fed by top/bottom plate of the SICL line. The other arm of the dipole is printed in between the two substrate of the SICL line and is excited by the middle strip of the SICL line. A SICL 1:4 power divider is employed to feed four crossed dipole antenna to form an array. The array exhibits a gain of 9.7 dBi and 10 dBi at 26 GHz and 28 GHz respectively with wide impedance bandwidth of 3.1 GHz. The cross polarization level better than 20 dB and Front-to-Back Ratio better than 17 dB is obtained for the proposed design. The proposed antenna finds its suitability for the much focused 5G millimeter wave frequency bands.

In this paper, we propose a novel Half Mode Substrate Integrated Coaxial Line (HMSICL) cavity fed monopole antenna at 28 GHz. A SICL cavity is bisected along its symmetric magnetic wall (PMC) to create an open-ended Half Mode SICL (HMSICL) cavity. The proposed HMSICL cavity is used to excite a tapered monopole antenna to radiate in endfire direction with a gain of 6.4 dBi at 28 GHz. For dual beam application, it is integrated with unidirectional broadside Half Mode Substrate Integrated Waveguide (HMSIW) antenna exhibiting a gain of 5.1 dBi that provides spatial diversity to the proposed design. To achieve high gain, two co- located 1× 4 linear HMSICL and HMSIW array are placed side-by-side such that the proposed design produces simultaneous endfire and broadside beams for In-Band Full Duplex (IBFD) applications. The proposed passive Signal Interference Cancellation (SIC) technique is utilized to minimize the overlap of simultaneous dual beam at 28 GHz by orienting the two antennas within a compact footprint. The full duplex antenna array achieves a gain of 10.8 dBi in endfire and 10.3 dBi in broadside direction with high isolation below 45 dB over 500 MHz bandwidth. The presented antenna array is a potential candidate for relay where the transmitting and receiving signals are in two different directions.

This article presents the modeling and realization of a compact substrate integrated coaxial line (SICL) based butler matrix operating at 5 GHz for beam-forming applications. The proposed 4 × 4 butler matrix is developed using SICL-based hybrid coupler, crossover, and phase shifter. A compact 90° coupler comprising of center tapped unequal stubs is designed to enhance the size reduction as well as to extend the out of band rejection. Wideband SICL-based crossover operating from DC to 10 GHz is conceived for the proposed butler matrix using a plated through hole as transition. The SICL crossover features very high measured isolation of 65 dB owing to the reduction in coupling between the two signal paths within a lateral footprint of only 0.034. A meandered SICL-based line is used in order to provide the necessary 45° and 0° phase shift to realize the butler matrix. The fully shielded and self-packaged compact 4 × 4 SICL-based butler matrix is fabricated and experimentally validated to operate at 5 GHz.

This paper presents Ka- band bias tee network designed in a Substrate Integrated coaxial line environment. The proposed circuit operates in the frequency range 31-35 GHz. A series of butterfly stub is used to realize inductor. To implement capacitor, interdigital structure is introduced in the middle layer of SICL. The size of this proposed circuit design is 1.1 \lambda\mathrm{g}\times 0.72 \lambda\mathrm{g}, where \lambda\mathrm{g} is guided wavelength at centre frequency of 33 GHz. The proposed results exhibit 0.1 dB insertion loss along with DC isolation 22dB with good impedance matching. The proposed circuit is very much suitable for Ka band active components application.

This paper presents Substrate Integrated Coaxial Line (SICL) fed wideband Multiple-Input Multiple-Output (MIMO) antenna array for 5G endfire applications. The radiating element in the array is a modified half-wavelength dipole antenna formed by tilted dipoles at ±45° to avoid overlapping between successive element in the array configuration. One arm is placed on the top while the other arm is placed on the bottom substrate and are respectively fed by top and middle plate (using a feeding via) of SICL line. The out of phase surface current of SICL feed line is utilized to successfully excite the dipole antenna. The top-bottom arrangement of the arms of the dipole antenna enables further compactness in the dimension of the array. SICL technology adds another advantage by reducing the coupling in the other port when one port is excited thereby high isolation is achieved using SICL. A four element MIMO antenna array for 360° azimuth coverage is proposed to exhibit a gain of 6 dBi with wide impedance bandwidth of 5.6 GHz and cross-polarization level below 13.6 dB at 28 GHz. The proposed MIMO antenna array is a potential candidate for 5G endfire applications in customer premises equipments (CPEs).

Design of a dual-polarized substrate integrated waveguide (SIW) based cavity-backed self-quadruplexing antenna is presented in this paper for fifth-generation (5G) millimetre-wave (mmWave) applications. In the proposed antenna, the metal plate at the top of the square SIW cavity is perturbed into eight rectangular patches of four different lengths each. The patches are designed/arranged to radiate into vertical and horizontal polarizations at 24.25, 26.5, 27.5, and 29.5 GHz simultaneously. With the proper placement of patches, isolation of more than 20 dB is obtained among the ports. The proposed antenna exhibits peak gains of 4.45, 4.28, 3.7, and 3.84 dBi at the above resonant frequencies. It has unidirectional radiation patterns with cross-polarization and front-to-back ratios better than 18 dB and 10 dB in all the bands. Moreover, the individual frequency-tuning capability of the antenna shows that it can be tuned to any of the mmWave 5G NR bands: n257, n258, n261 recommended by the U.S. Federal Communications Commission for 5G applications.

This study presents a wideband crossover developed using substrate integrated coaxial line (SICL) technology. The proposed SICL-based crossover isolates the two physically overlapping channels by routing the signal in a middle conductor of SICL through the transmission line created in the top and bottom ground plane using a metalised blind via. An equivalent model is proposed to study the role of substrate height in the proposed crossover. The design methodology is affirmed by fabricating and testing the experimental prototype. The measured results show isolation between channels are more than 19 dB with better than 18 dB return loss and less than 1.2 dB insertion loss from 0.2 to 20 GHz. Owing to the non-dispersive nature of SICL line and simplistic design technique with minimal discontinuities the designed crossover demonstrates low peak-to-peak group delay variation, less than 0.04 ns over the entire bandwidth. The proposed crossover due to its symmetric design provides low path difference of less than ±2.45° up to 20 GHz (≤ ±1° up to 10 GHz) without any additional phase compensation technique. Utilization of electromagnetically robust self-packaged components designed in SICL technology provides superior front-end communication system within a small footprint.

This paper presents a comparative study of cavity backed slot antenna design in two shielded planar technology, namely Substrate Integrated Coaxial Line (SICL) and Substrate Integrated Waveguide (SIW). Two SICL and one SIW based cavities are designed and analyzed in this work. First cavity is formed by placing two perfect electric conductor (PEC) boundaries and two perfect magnetic conductor (PMC) boundaries along the opposite edges of the Ag /2 x Ag /2 cavity. Further, a Substrate Integrated Waveguide (SIW) based cavity is formed by assigning PEC boundary along the four edges using via-holes. Two cavity backed slot antenna in the SICL and SIW based cavities are designed to operate at 28.3 GHz with a gain of 5.6 dBi and 5.7 dBi respectively. The antenna size in the SICL technology is ascertained to be compact in comparison to the SIW based design while maintaining similar performance. Thus, SICL based antenna can be employed in applications requiring miniaturized, conformal and compact antenna designs.