UWB Antenna Array Research Articles

Spatial positioning method based on UWB antenna array layout

Aiming at the problem of spatial positioning of dynamic targets in traditional power systems, this paper provides a cost controllable and high precision UWB antenna array layout method for spatial positioning to solve the problems of low precision and multiple restrictions of ultra wideband in spatial environment. First, a base station is set in each area. The base station contains a group of UWB antenna arrays composed of multiple antenna pairs. The distance L from the base station with the location tag is accurately measured through the UWB. Then, the UWB antenna array uses the PDOA phase difference principle to measure the direction of the signal. Finally, the spatial azimuth of the UWB signal from the tag to be located relative to the base station is calculated. The feasibility of the proposed method is verified by an example, which can significantly improve the positioning accuracy. The proposed method can provide strong technical support for intelligent operation and maintenance of power system and safe production.

Flexible Dual-Polarized UWB Antenna Sensors for Breast Tumor Detection

Detection of breast cancer in its early stage is critical for reducing the death rate. In this paper, a compact and flexible breast tumor sensing system is designed using dual-polarized UWB antenna arrays. Each UWB unit is composed of two orthogonally placed circular monopoles, which are printed on flexible and low-profile Kapton polyimide. The antennas are fed by single-side coplanar waveguides for size reduction. A wide band from 3.9 GHz to 19 GHz is obtained, with an isolation of above 16 dB over the operating band. High fidelity factors are achieved at different solid angles, indicating little distortion of the signal and stable sensing ability. To obtain the image of the tumor, eight UWB units are employed surrounding the breast phantom. Using the reflected and scattered signals from the antennas, 3D images of the breast are reconstructed using delay-and-sum (DAS) algorithm. Attributed to the dual-polarized UWB antennas, accurate location and size of the tumors are retained with little clutter. Moreover, the proposed system can detect two tumors with an edge to edge distance of 15 mm. Experiments have been carried out on rotating platforms, with the tumor successfully detected in the measurement. The proposed tumor sensing system is suitable for wearable applications due to its compact size and flexibility.

Slow Light Mode at the Degenerate Band Edge for True Time Delay Applications

Tuneable true time delay device is designed at the degenerate band edge (DBE) by using two coupled periodic silicon ridge waveguides. The holes of the two ridge waveguides are well-tuned to let four modes couple and degenerate at the bandgap providing a slow light mode (the DBE mode). Transfer matrix method is utilized to trace and verify the slow light mode in the device. A 25-unit cell device ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$10~ \boldsymbol {\mu m}$ </tex-math></inline-formula> length device) is constructed to realize the slow mode at the DBE with 70% transmission and 42.5 ps signal delay over 130 GHz dispersion free bandwidth. Liquid crystal cladding layer is incorporated to provide continuous control of the slow mode velocity around the DBE resonance for UWB antenna array beamforming applications.

A Novel Miniaturized Dual Slant-Polarized UWB Antenna Array with Excellent Pattern Symmetry Property for MIMO Applications

A novel miniaturized 1 × 10 uniform linear dual slant-polarized UWB antenna array for MIMO base station is presented. The antenna array operates in the frequency band from 1710 to 2690 MHz with a 17.3–18.7 dBi gain in a size of 105 × 1100 × 37 mm. The array element is composed of two single-polarized dipoles evolved from bow-tie antenna with slots on them, which miniaturize the size of the antenna. The 10 array elements are fed through an air dielectric strip-line power splitter. Two parameters, the beam tracking and the beam squint, are presented to quantitatively describe the pattern symmetry property of the antenna. The simulated and measured radiation performances are studied and compared. The results show that the pattern symmetry property of the single antenna element has been improved about 24% compared with the former study, and the antenna array also provides excellent pattern symmetry property.

Improvements in a 4-Element High Gain Directional UWB Antenna Array

In this paper, a novel serrated structure at the edges of the antipodal Vivaldi antenna is introduced. Compared with the Vivaldi antenna without serrated structure, the novel structure antenna has a better Front-to-Back ratio (F/B ratio). Additionally, when building a 4-element array with mirror image elements placed alternately along the H plane, the cross-polarization level at the boresight is reduced a lot compared to conventional array configuration. The design of the novel 4-element Vivaldi antenna array with mirror image elements described in this paper experimentally produces a gain with a range of 9∼15 dBi, F/B ratio more than 15 dB, and cross-polarization level at the boresight is reduced more than 10 dB from 3.5 GHz to more than 10.6 GHz with –10 dB return loss. The novel antenna array can be used for directional UWB systems.

Infrastructure-Aided Localization with UWB Antenna Arrays

This paper presents an approach for a precise 2D-localization of a mobile station in indoor scenarios by one single base station only. In the approach both, the Direction of Arrival (DoA) and the Time of Arrival (ToA), are estimated using UWB beamformers at both sides of the link. The article describes the algorithm, as well as the required hardware. A duallinear polarized, directive UWB antenna array is shown and the concept of UWB-beamforming network, based on FIR-filter is presented. Index Terms – UWB, Localization, Antennas, Arrays, Beamforming, FIR-Filter,

UWB antenna array for wireless transmission along corridors

AbstractA 2‐element elliptical patch antenna array with a bidirectional radiation pattern has been developed for ultra wideband indoor wireless communications. The array is constructed by means of feeding two omni‐directional elliptical patch elements with a 3‐section hybrid power divider. Experimental results show that the array has a stable radiation pattern and low return loss over a broad bandwidth of 64% (3.1–6 GHz). © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 886–890, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23232

Compact CPW-fed dual ellipses antenna for ultra-wideband system

A novel coplanar waveguide (CPW) antenna is proposed to operate from 2.9 to 13 GHz. It consists of an elliptic radiator, an elliptic ground plane and a CPW transmission line. The designed antenna has compact dimensions of 20 by 23 mm and an approximate omnidirectional pattern across the major bandwidth. This antenna can be especially applied as the element of UWB antenna arrays for UWB application.

Spatial correlation technique for UWB antenna arrays

A computation technique for predicting the spatial correlation coefficients, based on data captured by an ultra-wideband antenna array, is presented. Signal correlation coefficients obtained from adjacent array positions were calculated at each time bin. In addition, the application of this technique can lead to ultra-wideband multipath cluster identification. Time bins associated with high correlation values were selected as cluster arrival times and were compared with results estimated by the Sensor-CLEAN algorithm.