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This paper presents the design, accurate analysis and experimental validation of a large antenna array working in Ka-band. This passive array of 1024 radiating elements is designed to radiate linear polarization in the Rx sub-band of the Ka-band (19.7–20.2 GHz). The main challenge of this work is to obtain an accurate modelling of such a large array. Indeed, since the electrical length of the array...
Future communication links will require higher data rates, multiple beams, and higher transmit/receive gains, in addition to smaller weight, cost, and power. With the growing interest for reduced size platforms and the requirement for ultra-wideband (UWB) performance to address multifunctionality, there is a strong need for UWB apertures to enable increased spectral efficiency, multifunctionality...
The objective of this paper is to describe a least square method to compute the far field from a nonuniformly spaced antenna array. This is because the far field pattern of an antenna array is the Fourier transform of the current distribution developed on the antenna structure, This is equivalent to computing the spectrum from a nonuniformly spaced data set using a least squares method. The merit...
The objective of this paper is to describe a least square method to compute the far field from a nonuniformly spaced antenna array. This is because the far field pattern of an antenna array is the Fourier transform of the current distribution developed on the antenna structure, This is equivalent to computing the spectrum from a nonuniformly spaced data set using a least squares method. The merit...
An active millimeter wave imaging system with sparse antenna array for security inspection is introduced in this review. Several key parts and related techniques of the imaging system are explained and numerical results are provided.
Design of a control module for millimeter wave imaging system based on FPGA is presented in this paper. There are four parts in the module: scanning control module of antenna array, data acquisition and storage control module, ethernet transmission control module and mechanical scanning platform control module.
The far field pattern from a non-uniformly spaced antenna array is computed using a least squares method. The method originally developed for spectral estimation for a non-uniformly spaced finite data set is applied for the analysis of the far field pattern from unevenly spaced antennas, as the far field pattern is due to the spectrum of the location of the antenna elements. The advantage of using...
Array antenna has been utilized in many radio telescope systems, especially for low frequency transient observation, to increase their resolving power. In this paper, a new method to determine the maximum resolving power of an array radio telescope based on the single antenna beamwidth is proposed. The method is derived from theoretical calculations combined with simulations. Statistical result shows...
With the advent of the new class of radio telescopes as for example the LOw Frequency ARray (LOFAR) and the Square Kilometer Array (SKA) the necessity of using data mining procedures to handle the huge amount of data collected during their observations became crucial. Software design has resulted in a complete shift of methods by which information is collected in the radio frequency domain. Pointing...
This paper presents a technique to increase the data throughput in Multiple Input Multiple Output (MIMO) systems. The technique uses a meta-heuristic to optimize the data throughput and to choose the best solution. The optimization is based on Genetic Algorithms (GA), with the objective of finding out the best antenna configuration to achieve the highest data throughput from the variation of the distance...
A novel multi-dimensional noise-shaping method is proposed to extend Δ-Σ modulation to the two-dimensional (2-D) (space, time) case. It uses spatial oversampling to provide another degree of freedom for ADC designers to shape quantization noise when temporal oversampling is limited. The method uses lossless discrete integrators (LDIs) to implement spatial integrators and is suitable for use in microwave...
In this paper, we present a greedy sensor selection algorithm for minimum variance distortionless response (MVDR) beamforming under a modular budget constraint. In particular, we propose a submodular set-function that can be maximized using a linear-time greedy heuristic that is near optimal. Different from the convex formulation that is typically used to solve the sensor selection problem, the method...
Ground-based SAR has become an important remote sensing technology means for deformation monitoring in recent years. However, in order to achieve higher efficiency data acquisition and wider observation, arc antenna array technology is applied to ground-based SAR. In this paper, a polar format imaging algorithm for arc antenna array ground-based SAR is proposed. Firstly, a brief background on ground-based...
Radio frequency interference (RFI) has becoming a seriously limitation in the retrieval of geophysical parameters from the measurements of microwave radiometers. In this work, a novel RFI localization approach is presented here to improve the computationally complexity by using virtual arrays and direction of arrival (DOA) estimations techniques. The proposed RFI localization method utilizes the underlying...
The security of public places has been greatly concerned by the government and organizations in recent decades. Detecting the crowd flow in public places can help alerting the congestion of the channel immediately and making an immediate evacuation policy to prevent the occurrence of extrusion stampede. However, the common detection techniques require special additional hardware components that suffer...
It is necessary to study the spatial evolution of clusters in massive multiple-input multiple-output (MIMO) mobile channel, which is one of the important features in cluster-based models. In this paper, we analyze the data collected from the massive MIMO mobile measurement campaign, with a 256-element virtual array at 3.5 GHz in line of sight (LoS) and non line of sight (NLoS) conditions, respectively...
This paper presents angular characteristics for high-speed railway (HSR) channels, based on virtual single-input multiple-output (SIMO) measurements. A virtual array measurement scheme is investigated and used to generate SIMO channel impulse responses (CIRs) from single-antenna measurements in three typical HSR scenarios, including obstructed viaduct, deep cutting, and open station. According to...
Massive multiple-input multiple-output (Massive MIMO) is acknowledged as a key technology for the 5th generation (5G) of wireless communication systems, which theoretically proved to be of higher throughput, better robustness, superior spectrum- and energy- efficiency. A reliable and realistic channel model serves is the enabling foundation for practical design and testing of communication systems...
This paper tests and demonstrates the ability of a twin set of passive radar systems to monitor real time an area of interest and track medium size targets. The results are based on a real data acquisition campaign performed using two eleven element array antenna based passive radars in the Oslo fjord area in September 2016.
This paper presents a 32-element phased-array architecture suitable for fifth-generation (5G) communication links. A 28–32 GHz silicon core chip is designed with 4 transmit/receive elements each with 14 dB gain control, 6-bit phase control, 4.6 dB measured noise figure (NF) in the RX mode and 10 dBm output 1 dB compression point (OP1dB) in the TX mode. Eight of these chips are flipped on a low-cost...
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