摘要 :
In the design of reflection-type phase shifters, the coupler that represents the shifter's backbone is usually assumed to be a quarter-wavelength 3-dB coupler. In this paper, a derived theoretical model shows that, for certain val...
展开
In the design of reflection-type phase shifters, the coupler that represents the shifter's backbone is usually assumed to be a quarter-wavelength 3-dB coupler. In this paper, a derived theoretical model shows that, for certain values for the odd- and even-mode impedances, a coupled structure with a length that is less than one tenth of a wavelength is sufficient to build a high-performance reflection phase shifter. The presented analysis indicates that reflection phase shifters can be designed with a more compact size and larger phase range compared with the conventional method of using a quarter-wavelength 3-dB coupler. However, the required odd-mode impedance in the proposed design is low $({approx}hbox{10} Omega)$ , whereas the required even-mode impedance is high $({approx}hbox{200} Omega)$. To realize those impedances when using parallel-coupled lines, slotted ground and shunt chip capacitor are used. The proposed design is supported by full-wave electromagnetic simulations and measurements. The simulated results show that $0.085lambda$ coupled structure achieves 255$^{circ}$ phase range across 36% fractional bandwidth with less than 1-dB insertion loss and more than 10-dB return loss. In another design, a full-cycle phase range is obtained with less than 1.5-dB insertion loss across the same band by using two $0.076lambda$ coupled sections. A manufactured prototype for a full-cycle phase range validates the simulation results and, thus, the proposed method.
收起
摘要 :
Microwave and millimeter-wave ferrite phase shifters are essential components in phased-array antennas for telecommunication and radar applications. However, the extremely high cost and frequency limitations have limited their use...
展开
Microwave and millimeter-wave ferrite phase shifters are essential components in phased-array antennas for telecommunication and radar applications. However, the extremely high cost and frequency limitations have limited their use to military applications. In this study, potentially low-cost, miniaturized semiconductor phase shifters are analyzed and compared with their ferrite counterparts. Ferrite-semiconductor composite phase shifters are also envisaged.
收起
摘要 :
In this work, a compact and wideband Schiffman phase shifter is proposed using a microstrip transmission line. This proposed phase shifter incorporates a rectangular complementary split-ring resonator (CSRR) and two open stubs. It...
展开
In this work, a compact and wideband Schiffman phase shifter is proposed using a microstrip transmission line. This proposed phase shifter incorporates a rectangular complementary split-ring resonator (CSRR) and two open stubs. It is designed to get a phase shift of 90° with ±5° phase imbalance for the frequency range of 1.47-3.52 GHz. It shows a fractional bandwidth of 85.41% at the center frequency of 2.4 GHz. The proposed design occupied a total area of 0.067 λ_g ~2. The proposed structure is fabricated and validated, there is a good agreement between the simulated and measured results.
收起
摘要 :
In this paper, one improved wide-band Schiffman phase shifter is presented by modifying the ground plane underneath the coupled lines. In this new design, with the ground plane under the coupled lines removed, the even-mode impeda...
展开
In this paper, one improved wide-band Schiffman phase shifter is presented by modifying the ground plane underneath the coupled lines. In this new design, with the ground plane under the coupled lines removed, the even-mode impedance will be increased substantially. Meanwhile, we propose that one additional isolated rectangular conductor is placed under the coupled lines to act as one capacitor so that the odd-mode impedance is decreased. The proposed new design was simulated by the full-wave electromagnetic software IE3D and validated by the measurement. Compared with the cascading microstrip multisection coupled-line configuration, our newly proposed planar one with a patterned ground plane is small in size and, meanwhile, has a good performance. As an example, one Schiffman phase shifter on a double-sided printed circuit board is designed, simulated, fabricated, and measured. The measured amplitude and phase imbalance between the two paths are within 0.5 dB and 5 deg, respectively, over the frequency band from 1.5 to 3.1 GHz, or around 70percent bandwidth. The measured return loss is found to be better than -12 dB over the operating frequency band.
收起
摘要 :
This paper proposes a new vector-sum type variable-phase shifter (VPS) topology for predistorting the phase of a modulated signal for an analog-predistortion power amplifier system. It has a continuous linear-in-degree control cur...
展开
This paper proposes a new vector-sum type variable-phase shifter (VPS) topology for predistorting the phase of a modulated signal for an analog-predistortion power amplifier system. It has a continuous linear-in-degree control curve over a 90$^{circ}$ phase-control range and has the smallest size among all those proposed CMOS works. The phase shifter utilizes an improved RC poly-phase filter to generate in-phase and quadrature-phase vectors. It uses fewer RC components but has a wider phase-splitting bandwidth than traditional RC filters, reducing the loss and size of the overall VPS. Specially-designed control circuits give the shifter a linear phase-control capability, minimizing the gain variation over the phase-control range. The phase shifter, optimized for WCDMA applications, has been fabricated in a standard 0.18-$mu$m CMOS process. The area of the phase shifter core is 0.063 mm$^{2}$ . The measured operation frequency is from 1 to 2.1 GHz, which is an overlap of its 3-dB cutoff frequency and bandwidth of a 90 $^{circ}$ phase-control range. Within the bandwidth, this phase shifter displays a linear control curve with phase errors of less than $pm 1^{circ}$ over a 70$^{circ}$ tuning range, making it suitable for accurate AM-PM error compensation.
收起
摘要 :
This paper presents a novel 4-bit phase shifter using distributed active switches in 0.18-$mu{hbox {m}}$ RF CMOS technology. The relative phase shift, which varies from 0$^{circ}$ to 360$^{circ}$ in steps of 22.5$^{circ}$, is ach...
展开
This paper presents a novel 4-bit phase shifter using distributed active switches in 0.18-$mu{hbox {m}}$ RF CMOS technology. The relative phase shift, which varies from 0$^{circ}$ to 360$^{circ}$ in steps of 22.5$^{circ}$, is achieved with a 3-bit distributed phase shifter and a 180$^{circ}$ high-pass/low-pass phase shifter. The distributed phase shifter is implemented using distributed active switches that consist of a periodic placement of series inductors and cascode transistors, thereby obtaining linear phase shift versus frequency with a digital control. The design guideline of the distributed phase shifter is presented. The 4-bit phase shifter achieves 3.5$pm$0.5 dB of gain, with an rms phase error of 2.6$^{circ}$ at a center frequency of 12.1 GHz. The input and output return losses are less than $-$15 dB at all conditions. The chip size is ${hbox {1880}} mu{hbox {m}}times {hbox {915}} mu{hbox {m}}$ including the probing pads.
收起
摘要 :
This article describes an analog phase shifter able to provide a continuously tunable phase shift up to 180° by using a single all-pass unit cell. The proposed topology is compact and easy to implement, and brings an interesting ...
展开
This article describes an analog phase shifter able to provide a continuously tunable phase shift up to 180° by using a single all-pass unit cell. The proposed topology is compact and easy to implement, and brings an interesting compromise between phase variation, insertion and return losses. Indeed, for a 7.5:1 tuning ratio of varactor capacitance, a phase shift variation of more than 186° is obtained from 6 to 7 GHz with a maximum insertion loss of 1.8 dB. The 105°/dB resulting Figure-of-Merit is thus among the best in distributed approaches with varactors.
收起
摘要 :
In this work, a broadband dual-channel differential phase shifter is developed with a small phase deviation across a wide frequency range. The design consists of two main lines for 45° and 90° phase shifts, along with a referenc...
展开
In this work, a broadband dual-channel differential phase shifter is developed with a small phase deviation across a wide frequency range. The design consists of two main lines for 45° and 90° phase shifts, along with a reference line. A prototype is fabricated and measured to validate the performance of the design. Phase shifts of 45° ± 5° and 90° ± 5° over a frequency range of 1.26 GHz - 4 GHz (bandwidth of 104%) are achieved from the channels. The transmission losses of the three lines are less than 0.35 dB and the isolation between the adjacent ports is better than 20 dB. The area of this dual-channel differential phase shifter is ?(14.7 mm × 66.15 mm), where is the guided wavelength at the center frequency.
收起
摘要 :
A compact digital phase shifter is presented utilising negative phase velocity in metamaterial technology. The phase shifter was designed and it was measured ranging from 0deg to 360deg with discrete increments of 60deg. The measu...
展开
A compact digital phase shifter is presented utilising negative phase velocity in metamaterial technology. The phase shifter was designed and it was measured ranging from 0deg to 360deg with discrete increments of 60deg. The measurement result shows that the average increment of phase shift was X = 59.28deg and its standard deviation was sigma = 6.64deg.
收起
In this paper, the design of a rectangular waveguide metamaterial (MTM) phase shifter will be introduced in X band. The main disadvantages of the class of waveguide MTM phase shifters include high inserti
In this paper, the design of a rectangular waveguide metamaterial (MTM) phase shifter will be introduced in X band. The main disadvantages of the class of waveguide MTM phase shifters include high insertion loss (about 10 dB) and high DC magnetic bias field requirement (6‐7 kOe), that treated in the proposed phase shifter scheme by using toroidal shape ferrite core in conjunction with metalized parallel microstrip lines and implementing the multi‐section matching network, that leads to 3.2 dB insertion loss and a simple bias mechanism such as conventional toroidal phase shifter without consisting any high reluctance air‐gap, which could be implemented by no need of any feather coil system or higher current values. The results of simultaneous ENG and MNG design procedure for 288° differential phase shift with the 2 cm ferrite core length, shows 4 times compactness of proposed phase shifter in comparison with conventional toroidal phase shifter.
原文获取