- 标题
- 摘要
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- 实验方案
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A Phase-Calibration Method for Vector-Sum Phase Shifters Using a Self-Generated LUT
摘要： This paper presents a new self-calibration method for vector-sum phase shifters (PS) to compensate for process variations and achieve reconfigurable operating frequency. The calibration system generates a look-up table for the control voltages of the variable-gain amplifiers of the PS to minimize the rms phase error at a frequency of interest. The calibration system consists of a coupled-line coupler, an amplifier, a power detector (PD), an analog-to-digital converter, and a data processing unit. In this calibration method, first, the amplitudes of IQ vectors are swept and their powers are measured. Then, phase errors are calculated from these power measurements using the cosine formula. Finally, the vector pairs providing the least phase error are chosen for each desired phase shift. The practicality of the proposed system is demonstrated by realizing a self-calibrated X-band 7-b PS fabricated in IHP 0.25-μm SiGe BiCMOS technology, including the on-chip coupler, amplifier, and PD. The calibration system improves the rms phase error by at least 1°, does not degrade the rms gain error, and increases the insertion loss by 1.6 dB. The self-calibrated PS achieves a 2° rms phase error across X-band frequencies. The overall chip size is 2.6 mm2. The power consumption of the PS and the overall system are 110 and 233 mW, respectively. This built-in calibration system mitigates process variation effects, and the performance of the PS can be optimized for any center frequency across X-band.
关键词： BiCMOS,vector-sum phase shifter,look-up table,Self-calibration,process compensation,phase shifter,SiGe
更新于2025-09-23 15:23:52
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In-band phase deviation minimization method for wideband tunable phase shifter
摘要： This article provides a novel approach to analyze and design wideband tunable reflection-type phase shifter (RTPS) with low in-band phase deviation (IBPD) error. The proposed RTPS consists of coupled lines where through and coupled ports are terminated with varactor diodes. The coupled lines can minimize the parasitic elements of varactor diode to achieve high phase shift range (PSR). In addition, the measured frequency-dependent capacitance of varactor diode was used in the analytical analysis to obtain minimum IBPD error and high PSR. For experimental demonstration, phase shifter was fabricated at the center frequency of 2.5 GHz. The measured results show that the fabricated circuit achieved 126.85° PSR with ±6.48° IBPD error for 500 MHz bandwidth (BW). In addition, the measured maximum insertion loss variation and input/output return losses are within ±0.34 dB and higher than 16.85 dB within 500 MHz BW, respectively.
关键词： varactor diode,coupled line,low in-band phase deviation error,wideband tunable reflection-type phase shifter
更新于2025-09-23 15:23:52
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[IEEE 2018 48th European Microwave Conference (EuMC) - Madrid, Spain (2018.9.23-2018.9.27)] 2018 48th European Microwave Conference (EuMC) - Low-loss Loaded Line Phase Shifter for Radar Application in X Band
摘要： Losses in the phase shifters of phased arrays are one of the main limitations of these reconfigurable antennas. This contribution presents the design and measured results of variable phase shifters on triplicate suspended transmission lines in the microwave X-band for variable pointing radar applications. The antenna assembly remains passive and with a very low level of losses in the power distribution network and the phase shifters. PIN or varactor diodes are used to control the load on the transmission line. Each of these components has advantages and disadvantages that are discussed in the communication.
关键词： linear array,phase shifter,Pin diode,varactor,suspended strip
更新于2025-09-23 15:23:52
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[IEEE 2018 19th International Conference on Electronic Packaging Technology (ICEPT) - Shanghai (2018.8.8-2018.8.11)] 2018 19th International Conference on Electronic Packaging Technology (ICEPT) - Polymorphic impedance matching technique for MEMS phase shifter
摘要： The amplitude and phase consistency control level is an important factor affecting the performance of phased array antenna. MEMS phase shifter has important application potential in phased array antenna, but the current MEMS phase shifter device has poor amplitude and phase consistency, making it difficult to integrate directly in phased array antenna system. In this paper, a novel multi-states matching technology for MEMS phase shifter is proposed to overcome the above-mentioned difficulty. To control amplitude fluctuation and phase shift error of phase shifter in the using process, we proposed a general network design method focusing on the given polymorphic S parameter matrix of MEMS phase shifter based on the theory of microwave network. The key of the method is as following: with the help of the mature microwave network synthesis method and the particle swarm optimization algorithm combined by matching circuit parameter optimization, obtain actual S parameter matrixes of two polymorphic matching networks for the corresponding MEMS phase shifter, so as to enhance the amplitude and phase consistency integrated application. The simulation results verify the feasibility of the method, and so that we form a technical way to improve the consistency of amplitude and phase of MEMS phase shifter system through polymorphic matching network, which has important theoretical and practical value.
关键词： multi-states,MEMS phase shifter,matching technology
更新于2025-09-23 15:23:52
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Analogue Wireless Beamforming Exploiting the Fiber-Nonlinearity of Radio Over Fiber Based C-RANs
摘要： As a key technique of supporting the fixed backbone network, radio over fiber (RoF) systems transmit the radio frequency signals over optical fiber in order to take advantage of their large available bandwidth. In this context, optical fiber aided phased antenna array (PAA) based beamforming techniques have attracted substantial research interest with the goal of improving the cell-edge coverage of cellular base stations. In this paper, we conceive a novel optical fiber aided beamforming technique based on the fiber's nonlinearity to be applied in cloud radio access network (C-RAN). In our proposed technique, the PAA elements are fed by the phase-shifted signals introduced by our highly nonlinear fiber (HNLF) aided phase-shifting solution, which results in an angular beamsteering range of around 90°. This can be exploited by sectorization in cellular networks to reduce the cochannel interference imposed. Furthermore, we exploit the proposed RoF-aided phase shifting technique in C-RAN, where our proposed system takes advantage of the centralized signal processing capability of the RoF system to conceive an all-optical processing based tunable beamforming system. While our flexible HNLF-aided phase-shifting process is confined to the central office of the C-RAN, the end users in the C-RAN cellular networks are capable of flexibly choosing the serving remote radio heads (RRHs) and employing diverse wireless transmission techniques. Through integrating our HNLF-aided phase-shifting design into the proposed C-RAN, we impose as little as 0.1 dB signal-to-noise Ratio (SNR) degradation compared to its traditional electronic counterpart, which requires extra phase-shifters.
关键词： phase-shifter,self-phase modulation,phased array antenna beamforming,C-RAN,cross-phase modulation,highly nonlinear fiber,Optical fiber,optical nonlinearity
更新于2025-09-23 15:22:29
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Tunable Phase Shifter Based on Few-Layer Graphene Flakes
摘要： This letter presents a voltage-controlled tunable phase shifter based on few-layer graphene. The phase shifter consists of a stub-loaded line, composed of a microstrip line with a stub attached to it through a taper and graphene pad. The bias voltage applied to the graphene pad determines a variation of graphene resistance, which eventually causes the phase change. Without any voltage bias, graphene exhibits high resistance, thus isolating the stub and leading to a low phase shift. As the bias voltage is increased, graphene resistance is lowered, the effect of the stub is more pronounced, and the phase shift is increased. A prototype operating in the frequency range from 5 to 6 GHz has been designed and tested. The measured maximum phase shift obtained is 40°, and the corresponding degradation of the insertion loss is 3 dB.
关键词： tunable microwave devices,graphene,phase shifter,Few-layer graphene
更新于2025-09-23 15:22:29
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A true-time-delay transmit/receive module for X-band subarray phased arrays
摘要： This letter presents the implementation of a 6-bit true-time-delay (TTD) transmit/receive (T/R) module in X-band. Improved phase linearity is achieved by using thin film coplanar waveguide transmission lines than traditional microstrip lines or lumped LC components of the most other TTD designs. In order to meet the requirement of the large dynamic temperature range in practice, the hybrid coupler reflective phase shifters with varactor diodes are adopted in long-time-delay units as temperature compensations for thermal phase drift. Experimental results of this TTD T/R module are carried out within a bandwidth of 1.2 GHz at X-band. The gain flatness is better than 1 dB and RMSE of the phase errors is less than 7° in all the transmitting and receiving delay states.
关键词： true time delay (TTD),receive module,phased array,coplanar waveguide,phase shifter
更新于2025-09-23 15:22:29
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A microwave photonic phase-tunable mixer with local oscillator frequency doubling
摘要： A microwave photonic phase-tunable mixer with a doubled local oscillator (LO) frequency is presented based on an integrated dual-polarization dual-parallel Mach-Zehnder modulator (DP-DPMZM). A radio frequency (RF) signal is sent to one of the sub-DPMZMs via an electrical 90° hybrid coupler, and the carrier-suppressed single-sideband (CS-SSB) modulation is output. Another sub-DPMZM is modulated by a LO signal, and the 2nd-order carrier-suppressed double-sideband (CS-DSB) modulation is produced by combining a fiber Bragg grating (FBG). A single bias voltage of the modulator can change the phase shift linearly. The mixing signal with double LO frequency and phase shift can be acquired after the photodetector. Experimental setup is implemented, and the results indicate that the spur suppression ratios of the up/down-converted signals are 22.5 dB and 25.2 dB. The spurious-free dynamic range (SFDR) values are 102.97 dB·Hz2/3 in the down-conversion mode and 100.81 dB·Hz2/3 in the up-conversion mode. The phase shift can be varied continuously in the range of 360°. The proposed compact link is characterized by function multiplexing, half reduction of the LO frequency and high electrical purity.
关键词： Mixer,Microwave photonics,Phase shifter,Frequency doubling
更新于2025-09-23 15:22:29
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[IEEE 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - Paris (2018.7.8-2018.7.13)] 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - Study on the phase shifter in josephson junctions embedded microwave circuits
摘要： In a programmable Josephson voltage standard device which contains multiple branches of Josephson junction (JJ) array, the microwave reflection in arrays may result in a decrease in the Shapiro step margin. According to most of the previous designs, 90° phase shifter is used to cancel microwave reflection from branches to improve the performance of the device. This paper reports our study of the phase shifter in JJ array device with a 2-stage Wilkinson power divider. At first we designed and fabricated JJ array circuits with the phase shifters. Measurement results indicate that unequal powers have been reached to arrays. We then deleted the phase shifters in another design. Identical Shapiro step margins for 4 JJ array branches are achieved.
关键词： phase shifter,Josephson junctions,quantum voltage,superconducting
更新于2025-09-23 15:22:29
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A new dual band 4 x 4 butler matrix with dual band 3dB quadrature branch line coupler and dual band 45° phase shifter
摘要： A new dual band 4 × 4 butler matrix (BM) without crossover has been proposed, implemented and analyzed in this paper. A new dual band 45° phase shifter has also been proposed. The dual band BM, dual band 3dB quadrature branch line coupler (BLC) and dual band 45o phase shifter have been designed using Keysight Technologies’ Advanced Design System (ADS) software and implemented on the Rogers 2.33, having a thickness of 0.787 mm for 1.0 GHz and 2.5 GHz operating frequencies. Before the implementation of the proposed BM, the dual band 3dB quadrature BLC and dual band 45° phase shifter have been designed, implemented and analyzed. The proposed dual band 4 × 4 BM has been developed by placing four dual band 3dB quadrature BLCs and two dual band 45° phase shifters at their appropriate positions. Circuit parameters variation of the proposed BLC, phase shifter and BM with frequency ratios have been studied in this paper. The measured and simulated results of the dual band BM validated the design methodology. A performance analysis comparing the proposed BM with the existing butler matrices has also been carried out.
关键词： branch line coupler,Butler matrix,dual band,impedance transformer,45o phase shifter,advanced design system
更新于2025-09-23 15:21:21