- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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A Low-cost Ka-band Circularly Polarized Passive Phased-Array Antenna for Mobile Satellite Applications
摘要： This paper presents a low-profile, high-performance, and low-cost Ka-band circularly polarized (CP) passive phased-array antenna (PAA) system. A 1 × 4 passive sub-array 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 circularly polarized (RHCP) radiation with high cross-polarization discrimination over a wide scan angle from 0o to ±38o over the frequency band (29.5-30.5 GHz). An AR < 3dB is demonstrated over the entire scanning range. Moreover, the measured radiation efficiency is 60% at bore-sight. The gain drops by 1 dB at ±38o scanning angles.
关键词： satellite mobile communication,millimeter-wave phased-array antenna,phase shifter,Circularly polarized antenna
更新于2025-09-23 15:21:21
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A 28-GHz Low-Power Vector-Sum Phase Shifter Using Biphase Modulator and Current Reused Technique
摘要： In this letter, we present a low-power vector-sum phase shifter for upcoming 5G communication at 28 GHz. The ±I/±Q signals for phase synthesis by vector adder (VA) are generated by a 90° coupler and two re?ection-type biphase modulators. Modulators are only biased at 0 and 1.8 V to avoid large insertion loss near their phase reversal region. Our proposed single-ended two branches quadrature structure can avoid the differential variable gain ampli?er and achieve low power and compact area. In addition, we use the current reused technique to connect VA and output buffer to save dc power and suppress a change in output impedance among different phase states. The measured average peak gain is ?3.75 dB at 29.25 GHz. Across all phase states, the measured IP1 dB is better than 5 dBm. The 3-dB bandwidth of S21 is 27–33 GHz. Input and output return losses are also better than 10 dB at this frequency range. Total dc power consumption is only 6.6 mW for 1.8 V supplied voltage. To the best of our best knowledge, this phase shifter has low dc power and compact area at K-band and Ka-band.
关键词： vector adder (VA),phase-invertible variable attenuators (PIVAs),Biphase modulator (BM),current reused technique,vector-sum phase shifter (VSPS),buffer ampli?er (BA)
更新于2025-09-23 15:21:01
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A Switchable Diplexer Using Switchable Impedance Matching Circuit Technique
摘要： A new type of switchable diplexer is proposed by using switchable impedance matching circuit (SIMC) to connect two quasi-elliptic bandpass filters. The proposed SIMC consists of two different T-network phase shifters to provide the desired impedance matching and a pair of series-parallel configuration p-i-n diode switches to switch the channels on/off. The designed switchable diplexers have four available operation states, so that they realize multiple functional blocks in a single module. The fabricated switchable diplexer features compact size, wide passband, high isolation and independently switchable operation states.
关键词： Bandpass filter,p–i–n diode,switchable,Phase shifter,Diplexer
更新于2025-09-23 15:21:01
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Hybrid Precoding for Wideband Millimeter-Wave Systems with Finite Resolution Phase Shifters
摘要： In this paper, we study the hybrid analog-digital precoding for OFDM based-wideband millimeter wave (mmwave) communication systems. Since the analog precoding matrix is performed in the time domain and used for the entire bandwidth while the digital precoding matrices are performed on a per-subcarrier basis, the resulting wideband hybrid precoding problem becomes very complicated. Moreover, in practice phase shifter (PS) usually has only finite resolution, which brings more difficulties. To solve the resulting difficult problem, we propose an efficient algorithm by leveraging the penalty decomposition method. Simulation results are finally provided to confirm the effectiveness and superiority of the proposed algorithm and show the performance improvement than the existing algorithm.
关键词： finite resolution phase shifter,wideband hybrid precoding,decomposition method,Wideband millimeter wave communication
更新于2025-09-23 15:21:01
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[IEEE 2019 34th Symposium on Microelectronics Technology and Devices (SBMicro) - Sao Paulo, Brazil (2019.8.26-2019.8.30)] 2019 34th Symposium on Microelectronics Technology and Devices (SBMicro) - Effect of the dopant location and the number of Bragg mirrors on the performance of superlattice infrared photodetectors
摘要： This paper presents a substrate integrated waveguide Butler matrix with a modi?ed hybrid coupler, operating from 28 to 32 GHz. The modi?ed hybrid coupler is realized by using 90? hybrid coupler followed by a ?45? compensating phase shifter. Thus, 45?/135? output phase differences can be obtained using this type of coupler. Compared with the equal-length unequal-width phase shifter, the compensating phase shifter exhibits better phase characteristics, with only 3? phase error over 28–32 GHz. Because the phase of compensating phase shifter is not realized by taking the phase introduced by the crossover as a reference, it gives great ?exibility to the design of compensating phase shifter. Adopting the modi?ed hybrid coupler, the designed Butler matrix features the output phases with peak to peak error of 13? and wideband performance from 28 to 32 GHz. The slot array fed by the Butler matrix can radiate four slanted beams with acceptable measured gains, in the range of 9.7～12 dBi for port 1 excitation and 8.4～11.1 dBi for port 2 excitation. The radiated beams can reach a wide azimuthal coverage between ±61?.
关键词： Butler matrix,Modi?ed hybrid coupler,substrate integrated waveguide (SIW),compensating phase shifter,slot array antenna
更新于2025-09-23 15:19:57
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SIMULATION OF CO-PLANAR WAVEGUIDE LIQUID CRYSTAL BASED PHASE SHIFTER
摘要： This paper discussed the design and performances of a liquid crystal phase shifter that can be used in tuning devices. Tuning devices growth with the demand in the emerging in telecommunication system. Tuning devices with smooth continuous phase shifting at low cost and compact size would be an advantage. This paper proposed a phase shifter using 5CB liquid crystal material. The advantages of using the material is the smoothness and continuity of the transitions in the phase shift. It is done by having a structure with cavity filled with the liquid crystal and applied with certain voltage that can be changed. The changes in voltage would change the applied electric field, and thus would change the permittivity of the material. The changes would affect the wave propagation and thus contribute to the phase shifting. The performance of the phase shifter was tested by means of simulation using CST Suite 2014 software. The results show that the higher the frequency, the higher the phase shift would occur. The highest FoM achieved is 68 (deg/dB) at 8 GHz. A phase shifter with smooth and continuous phase shift can be used as the feeding network in an array scanning antennas systems.
关键词： tunable materials,liquid crystal,FoM,CPW,Phase shifter
更新于2025-09-23 15:19:57
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[Institution of Engineering and Technology 12th European Conference on Antennas and Propagation (EuCAP 2018) - London, UK (9-13 April 2018)] 12th European Conference on Antennas and Propagation (EuCAP 2018) - Electronically tunable phase shifter with enhanced phase behaviour at Ku Band
摘要： We present the design of a microwave phase shifter at Ku band for active steerable array devices, with enhancement in its phase range. The device is based on a hybrid coupler with two of its ports loaded with reflective circuits. The reflective circuit provides the tunable nature to the device by means of electrically tunable varactors. This circuit includes impedance transformation to extend its phase variation range. The document includes the design of the shifter components, mainly focused on the reflective circuit design, and a complete shifter design.
关键词： reflective phase shifter,Ku band,active antennas
更新于2025-09-19 17:15:36
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Wide-Band Filtering Three-Port Coupler with Inherent DC-Blocking Function
摘要： This paper presents a novel wide-band filtering three-port coupler with inherent DC-blocking function, which is simply comprised of a power divider with wideband filtering function and a broadband phase shifter with a modified coupled line. For demonstration, a designed prototype operating at 3 GHz is simulated, fabricated, and measured. From the simulated and measured results, the coupler shows a 49% filtering bandwidth with 12-dB return loss and 90±5° phase shifting. The amplitude imbalance between the two output ports is less than 0.5 dB. The all-passband isolation is below -13 dB and the 25.7-dB upper stopband rejection is up to 5.4 GHz. The good agreement between the simulated and measured results validates the proposed idea. Hence, the proposed coupler is well suited for applications of wideband, filtering, and single-layer circuitry integration.
关键词： filtering,power divider,DC-blocking,phase shifter,wideband,Coupler
更新于2025-09-19 17:15:36
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Rapid Recovery of CIGS Solar Cells from PID Stress with Light Soaking
摘要： This paper presents a substrate integrated waveguide Butler matrix with a modi?ed hybrid coupler, operating from 28 to 32 GHz. The modi?ed hybrid coupler is realized by using 90? hybrid coupler followed by a ?45? compensating phase shifter. Thus, 45?/135? output phase differences can be obtained using this type of coupler. Compared with the equal-length unequal-width phase shifter, the compensating phase shifter exhibits better phase characteristics, with only 3? phase error over 28–32 GHz. Because the phase of compensating phase shifter is not realized by taking the phase introduced by the crossover as a reference, it gives great ?exibility to the design of compensating phase shifter. Adopting the modi?ed hybrid coupler, the designed Butler matrix features the output phases with peak to peak error of 13? and wideband performance from 28 to 32 GHz. The slot array fed by the Butler matrix can radiate four slanted beams with acceptable measured gains, in the range of 9.7～12 dBi for port 1 excitation and 8.4～11.1 dBi for port 2 excitation. The radiated beams can reach a wide azimuthal coverage between ±61?.
关键词： Butler matrix,Modi?ed hybrid coupler,substrate integrated waveguide (SIW),compensating phase shifter,slot array antenna
更新于2025-09-19 17:13:59
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Liquid Crystal-Based Enclosed Coplanar Waveguide Phase Shifter for 54a??66 GHz Applications
摘要： A 0–10 V bias voltage-driven liquid crystal (LC) based 0–180? continuously variable phase shifter was designed, fabricated, and measured with insertion loss less than ?4 dB across the spectrum from 54 GHz to 66 GHz. The phase shifter was structured in an enclosed coplanar waveguide (ECPW) with LC as tunable dielectrics encapsulated by a unified ground plate in the design, which significantly reduced the instability due to floating effects and losses due to stray modes. By competing for spatial volume distribution of the millimeter-wave signal occupying lossy tunable dielectrics versus low-loss but non-tunable dielectrics, the ECPW’s geometry and materials are optimized to minimize the total of dielectric volumetric loss and metallic surface loss for a fixed phase-tuning range. The optimized LC-based ECPW was impedance matched with 1.85 mm connectors by the time domain reflectometry (TDR) method. Device fabrication featured the use of rolled annealed copper foil of lowest surface roughness with nickel-free gold-plating of optimal thickness. Measured from 54 GHz to 66 GHz, the phase shifter prototype presented a tangible improvement in phase shift effectiveness and signal-to-noise ratio, while exhibiting lower insertion and return losses, more ease of control, and high linearity as well as lower-cost fabrication as compared with up-to-date documentations targeting 60 GHz applications.
关键词： tunable circuits and devices,true time delay,millimeter-wave,60 GHz,liquid crystal,phase shifter,enclosed coplanar waveguide
更新于2025-09-19 17:13:59