AR

A.G. Roederer

Authored

20 records found

Orthogonal Versus Zero-Forced Beamforming in Multibeam Antenna Systems

Review and Challenges for Future Wireless Networks

Orthogonality in multibeam antennas is revisited. The difference between orthogonal beamforming and zero-forced beamforming is highlighted. The intriguing relation between orthogonality, reciprocity and losses is recapitulated. Different approaches on the design of orthogonal bea ...

Concentric Ring Array Synthesis for Low Side Lobes

An Overview and a Tool for Optimizing Ring Radii and Angle of Rotation

A comprehensive review on the approaches for synthesizing low side lobe concentric ring array (CRA) antennas is given. An Iterative Convex Optimization (ICO) based array layout synthesis technique is proposed for peak side-lobe level (PSLL) minimization over a given circular fiel ...
The encouraging potential of employing large-scale aperiodic base station arrays in addressing the radiation pattern and thermal requirements of the next generation communication systems is demonstrated. Sample 256-element layout-optimized multibeam arrays are presented as a futu ...

Thermal-Aware Synthesis of 5G Base Station Antenna Arrays

An Overview and a Sparsity-Based Approach

Heat removal capabilities and radiation performances of several sparse antenna array topologies are studied for cooling enhancement in 5G millimeter-wave base station antennas. Both electromagnetic and thermal aspects are jointly considered for the first time in array layout opti ...
In this article, a concept of a phased antenna array based on substrate integrated waveguide (SIW) technology for 5G base stations is proposed. The array has a cosecant radiation pattern in the vertical plane for uniform illumination in a sector area. The array itself consists of ...
A novel stepped-amplitude aperiodic phased array synthesis method is proposed. The presented technique is based on iterative convex element position perturbations and uses pre-defined excitation amplitudes. A 64-element irregular array with two discrete amplitude levels (0.5 at t ...
An irregular antenna synthesis technique with jointly optimized array subset layouts has been proposed for efficient beam setup and reliable communication in 5G. The proposed approach addresses both the electromagnetic and thermal challenges in 5G arrays by integrating zooming an ...
A novel two-port, dual-band square-ring microstrip antenna element for wide-angle scanning planar phased array is proposed. The two ports are used to operate the antenna array over the L and S radar bands. Microstrip square-ring radiators are chosen due to their smaller dimension ...
The impact of reducing the total number of elements in passively-cooled, chip-integrated and space-tapered 5G base station antenna arrays on inter-beam interferences and chip temperatures is investigated for multi-user spacedivision-multiple-access applications. A convex element ...
A frequency reconfigurable phased array element is presented. The operational band of the single port L/S-band antenna can be selected by modifying the element apertures with p-I-n diode switches. The antenna element satisfies strict requirements on its frequency band separation ...
Minimization of the maximum sidelobe level for a given array geometry, amplitude distribution, and nulling sectors by phase-only adjustment of the element coefficients is studied. Nonlinear optimization problem for phase distribution is solved using a novel iterative convex optim ...
An extended-feature, system-driven convex algorithm for the synthesis of uniform-amplitude, irregular planar phased arrays with simultaneous multi-beam optimization for mm-wave 5G base station applications in multi-user scenarios is presented. The inter-user interferences are sup ...
An unconventional, yet quasi-modular base station phased array architecture synthesis technique is proposed for multiuser fifth-generation applications. By keeping uniform amplitudes and linearly progressing phases at the elements of an optimal irregular array, power-efficient si ...
In this paper, we present a 5G base station phased antenna array concept based on the power equalization in the elevation cut. We designed aperture coupling microstrip patch array exploiting a substrate integrated waveguide structure as feeding line for realization of the cosecan ...
The thermal and electromagnetic effects of varying the ground plane thickness and aperture size of the 5G integrated base station antennas are investigated. A double-sided PCB structure is designed with antennas and digital beamforming chips on the opposite sides. Fully-passive c ...
A novel hybrid beamforming architecture based on aphased array of active multiport subarrays is proposed for multi-user 5G applications. The subarrays have multiple simultaneous fixed beams which are smartly combined at the user locations withrelatively large gains towards th ...
This paper presents a 5G downlink system model for a hybrid multi-user beamforming technique at the base station. The presented technique employs power flux equalization in the elevation plane using a fixed analog cosecant-shaped beam and digital beamforming in the azimuth plane. ...
A convex iterative algorithm for the synthesis of uniform amplitude, space-tapered linear phased arrays with simultaneous multiple beam optimization for 5G applications is presented. The performance of the algorithm is demonstrated by the synthesis of two arrays having 16 and 24 ...
The performance of space-tapered multi-beam arrays with minimized side lobe levels is statistically evaluated in a line-of-sight propagation environment within a cell sector in terms of the signal-to-interference-plus-noise ratio at the multiple user ends. Comparative analyses ar ...
This paper discusses the advantages and an example of using shaped elevation patterns for 5G base stations. A simple iterative power synthesis method involving the phase of shaped patterns, and suitable for both center- and end-fed sub-arrays, is used. Numerical simulations and s ...