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In this article, the design and implementation of a low-loss bidirectional microelectromechanical system (MEMS)-like passive beamformer for emerging millimeter-wave (mm-Wave) applications are illustrated. A 4 $\times $ 4 phased-array antenna (PAA) is fabricated employing the proposed beamformer for demonstration. The phase shifter (PS) embedded in the beamformer operates based on the principle of loaded-transmission line (TL) PSs. Slow wave mechanism is employed to shrink the size of the PS. The PS measurement results show the average insertion loss (IL) of 1.3 dB in all the tuning states and the IL variation is 0.9 dB. The PS provides 380° of the phase tuning range in a compact footprint area of 2.4 mm $\times $ 3 mm. The antenna array incorporates slot-coupled patch antennas with left-handed circularly polarized (LHCP) radiation. The operating frequency bandwidth of the antenna system ranges from 28 to 30 GHz to provide co-pol/X-pol discrimination of more than 12 dB for all the steering angles. Measurement results show the beam steering angular range of ± 30° in both elevation and azimuth planes. The measurement results also show the peak directivity of 18.48 dBic and the radiation efficiency of 58% at boresight at the frequency of 29 GHz. The efficiency drops 16% when the steering angle reaches the maximum. [ABSTRACT FROM AUTHOR]

A high-efficiency 27–30 GHz 0.13- ${{\mu } \text {m}}$ BiCMOS transmitter front end for mobile satellite communication (SATCOM) phased arrays is presented. A system-level analysis for determining the key parameters of the RF front end for the case of a SATCOM user terminal for geostationary Earth orbit (GEO) is presented. The building blocks of the beamformer, consisting of a phase shifter, variable attenuator, and power amplifier, are fully characterized. A 360° phase shifter with an accuracy of 7 bits and amplitude error of ±1.5 dB is integrated with a variable attenuator that provides a gain variation of 16 dB with phase error of ±5°. The chip has a measured transducer gain of 23 dB and a power consumption of 45 mW at OP1dB of 10.8 dBm. The power-added efficiency (PAE) of 26.7% is measured for the entire channel at OP1dB. An error vector magnitude (EVM) of −28 dB at Pout,avg of 6 dBm and PAEavg of 12% is measured for a 400-MHz bandwidth 64-QAM modulated signal. The overall size of the chip is ${1.18} \times {2.23}\,\,\text {mm}^{{2}}$. [ABSTRACT FROM AUTHOR]

A low-cost and low-profile $Ka$ -band passive phased-array antenna (PAA) using continuously tunable substrate-integrated waveguide (SIW) phase shifter is presented in this article. The phase shifting mechanism is based on perturbing the electric field of the slotted SIW (SSIW) line by putting a high dielectric constant slab over the slot of SIW. A systematic approach based on a simple transmission line (TL) circuit model which can support different modes is developed as a fast method for design optimization. It provides insightful physical understanding of the operating mechanism of the proposed phase shifter. In addition, a fully verified TL model of the $1\times 4$ SIW PAA is presented and used to predict and optimize the overall reflection coefficients and radiation patterns at different scanning angles. The TL circuit model is verified by full-wave simulations. As a design example, a $1\times 4$ SIW-based phased-array is designed, fabricated, and measured to validate phase shifter performance and capabilities. The prototype exhibits a continuous beam scanning range from −20° to +20° covering the whole operating band of 29–31 GHz. [ABSTRACT FROM AUTHOR]

This letter presents a low-cost, low-profile, and high-performance $Ka$ -band continuously tunable substrate integrated waveguide (SIW) phase shifter. The proposed phase shifter consists of a slot cut on the SIW’s broad wall and a high dielectric constant slab over the slot. The phase-shifting mechanism is based on perturbing the electric field of the SIW’s fundamental mode, TE10-like, by putting a high dielectric constant slab over the slot of SIW structure to create slow wave phenomena. A prototype is designed, fabricated, and measured. The fabricated phase shifter exhibits linear phase–frequency response behavior with an average insertion loss less than 1.5 dB with an insertion loss variation less than 0.5 dB over a phase shift range of 275° in the operating frequency band (29–31 GHz). The phase shifter consumes a maximum of 25-mW power. [ABSTRACT FROM AUTHOR]

This paper presents the design, development, and measurement results of a low-cost integrated circularly polarized (CP) active phased-array antenna (CP-APAA) technology with sidelobe level (SLL) control, operating at $Ka$ -band, for high throughput land-mobile satellite communication. The proposed CP-APAA is comprised of ($4\times 16$) 64 elements in a rectangular grid array configuration. Eight commercial monolithic monolithic microwave/millimeter-wave integrated circuit. (MMICs) with eight-RF output channels have been used to control the phase and amplitude over the antenna aperture. For simplicity, the array antenna was designed in three metal layers and fabricated by a low-cost printed circuit board (PCB) technology as a proof-of-concept for a modular and scalable $Ka$ -band PAA with a wide steering angle. Measured radiation pattern shows a right-hand CP (RHCP) pattern with an axial-ratio (AR) level < 3 dB and low pointing error ≤1.5° over a scanning angular range of 0° to ±40°. Moreover, the amplitude excitation of the CP-APAA was tapered exponentially to control and reduce the SLL from 11 to 25 dB in boresight direction. Finally, toward a multibeam array implementation, two RHCP beams have been simultaneously generated at −30° and +20° scan angles. [ABSTRACT FROM AUTHOR]

In this article, efficient integration approach of building large‐scale active‐phased array antenna (A‐PAA) for millimeter‐wave (mm‐wave) is presented. In this approach, large‐scale A‐PAA is constructed from smaller size A‐PAAs (modules) with inter‐element spacing of half‐wave length and assembled into efficient planar waveguide feeding platform based on substrate integrated waveguide (SIW) technology. Simple low profile vertical RF‐connection between the SIW splitter/combiner outputs and the modules using surface mount super‐mini board‐to‐board (SM‐SMC) is presented. Embedded metallic via‐pad transition integrated into the SIW board is employed to match the SM‐SMC to the SIW mode at Ka band. Sixteen‐way power splitter with transitions to SM‐SMCs is designed at 30 GHz. The measured results of S‐parameters show insertion loss of <0.70 dB over the operating frequencies 28.50‐30.50 GHz. [ABSTRACT FROM AUTHOR]

This paper presents a low-profile, high-performance, and low-cost Ka-band circularly polarized (CP) passive phased-array antenna (PAA) system. A $1\times 4$ passive subarray operating at the Ka-band frequency band is investigated, developed, and tested as a possible building block for mobile satellite communication systems. In particular, a CP antenna integrated with a high-performance passive phase shifter is presented and experimentally verified. A new low-cost and low-profile magnetic actuator is proposed to precisely control the phase state of the phase shifter. A 3-D printed polymer package is utilized to enclose the phase shifter and reduce the environmental effects. The proposed CP passive PAA achieves high-performance right-hand CP radiation with high cross-polarization discrimination over a wide scan angle from 0° to ±38° over the frequency band (29.5–30.5 GHz). An axial ratio (AR) < 3 dB is demonstrated over the entire scanning range. Moreover, the measured radiation efficiency is 60% at boresight. The gain drops by 1 dB at ±38° scanning angles. [ABSTRACT FROM AUTHOR]

In , author Guoyan Chen’s biography appeared incorrectly. It is set in its correct form below. [ABSTRACT FROM AUTHOR]