Microwave Sampling Beamformer—Prototype Verification and Switch Design

Farzaneh, S.; Sebak, Abdel-Razik

doi:10.1109/tmtt.2008.2009080

Cited by 42 publications

(10 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…U n (t) + jU n (t) denotes an I/Q complex modulation technique applied to realize single-sideband time-modulated phase-only weighting. The new single-beam scanning scheme based on rectangular pulses and trapezoidal pulses [21], respectively, is presented and aims to make a comparison of the performances of the array between these two kinds of modulating pulses.…”

Section: Mathematical Formulationmentioning

confidence: 99%

“…To achieve the phase shift variation in the range of [−2π, 0], (t 1n /T p ) should be in the range of [−1/6, 5/6]. Unlike the previous work [14]- [21] where the duration of "on" time is changed, it is a constant value in this paper as provided in (16). Thus, the following relationship for each element holds…”

Section: A Rectangular Pulses For Single-sideband Time-modulated Phamentioning

confidence: 99%

“…A steered beam at the single-sideband with the effective suppression of the undesired sidebands can be realized by using (24) together with (21), (16), and (13). Note that based on the proposed I/Q complex modulation technique, the amplitude of each element is kept constant with the changing of beam-pointing angle θ.…”

Section: A Rectangular Pulses For Single-sideband Time-modulated Phamentioning

confidence: 99%

“…6. Then, the needed time switching functions U n (t) can be obtained from (13), (16), and (21). The resulting radiation patterns obtained from the array factor (solid line) and full-wave analysis (dotted line) scanned at these two angles are separately plotted in Fig.…”

Section: A Example 1: Rectangular Pulses (δ/T P = 0)mentioning

confidence: 99%

“…On the other hand, since time-average phase weightings are achieved at the harmonic frequencies, multiple harmonics have been utilized to realize beam scanning and beamforming without using digital phase shifters in TMAs [13]- [19]. In addition, the microwave sampling beamformer (MSBF) proposed in [20] and [21] was used to realize amplitude and phase weighting at the first positive harmonic frequency for phased array antennas, which is actually the same as the TM technique in TMAs. Yet, the TM technique has not been used for steering the beam at the single positive or negative sideband in phased array.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Single-Sideband Time-Modulated Phased Array

Yao

Fang

2015

IEEE Trans. Antennas Propagat.

123

View full text Add to dashboard Cite

A new in-phase/quadrature (I/Q) complex modulation technique to realize single-sideband time-modulated phaseonly weighting on an array antenna is proposed. Based on modulating rectangular pulses and trapezoidal pulses, the theories of generating a scanning beam at the single positive sideband are presented. It was found that using trapezoidal pulse modulation can obtain excellent performance in power efficiency and undesired sideband level than using rectangular pulse modulation. Unlike conventional time-modulated antenna array where each array element is connected to a RF switch, in the proposed scheme, each element is connected to an I/Q channel modulator which is composed of two Wilkinson power dividers, two RF switches, two 0/π phase shifters in RF channels, and one π/2 fixed-phase shifter in the control circuit. By properly controlling both the phase shifters and the switches in time domain, the single-sideband modulation can be realized with the uniform amplitude and variable phase in frequency domain. The I/Q modulator acts as a phase shifter and can be used to form a phased array. In this paper, the main efforts have been paid to find the pulse sequences to suppress the spurious bands. To validate the proposed technique, simulated results of an eight-element single-sideband time-modulated linear array obtained from the array factor and full-wave analysis are reported. In the case of using rectangular pulses, the power efficiency of the scanning beam is 91.47% and the peak level of the highest undesired harmonic is −13.98 dB. In the case of using trapezoidal pulses, the best values can reach 99.79% and −27.98 dB.Index Terms-In-phase/quadrature (I/Q) complex modulation, phased array, single-sideband time-modulated phase-only weighting, time-modulation (TM) technique.

show abstract

Section: Mathematical Formulationmentioning

confidence: 99%

Section: A Rectangular Pulses For Single-sideband Time-modulated Phamentioning

confidence: 99%

Section: A Rectangular Pulses For Single-sideband Time-modulated Phamentioning

confidence: 99%

Section: A Example 1: Rectangular Pulses (δ/T P = 0)mentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Single-Sideband Time-Modulated Phased Array

Yao

Fang

2015

IEEE Trans. Antennas Propagat.

123

View full text Add to dashboard Cite

show abstract

Design and implementation of an adaptive beamformer for phased array antenna applications

Adamidis

Vardiambasis

Ioannidou

et al. 2020

Micro & Optical Tech Letters

View full text Add to dashboard Cite

A modular beamformer, fully scalable in amplitude and phase, to be used with transmitting antenna arrays operating in the Digital Cellular System (DCS)/Personal Communications Service (PCS) frequency band, is designed and fabricated in this paper. The implementation of the structure is simple and very low cost; its performance is evaluated by measuring the frequency response, as well as the radiation patterns produced by an antenna array connected to the output of the beamformer. The latter exhibits low return losses and average amplitude imbalance less than ±0.8 dB, whereas the phase deviations do not exceed ±6° on average, over its 300 MHz bandwidth.

show abstract