Beamforming Receiver Research Articles

Design of a Digital Receive Beamformer ASIC Based Ultrasound Imaging System Prototype

This paper presents the design of an eight-channel digital receive beamformer application-specific integrated circuit (ASIC) based ultrasound (US) imaging system. The designed prototype system supports up to 64 transmit and 16 receive channels. ASIC-based 16-channel US transceiver board is designed for frontend processing, and for backend processing Intel[Formula: see text] Core™-i5 based PC is employed. The transceiver board employs two ASICs for digital receive beamforming and a field-programmable gate array (FPGA) for transmit beamforming and system control. The necessary power supplies for the transceiver board are provided by a custom designed and developed high voltage (HV) and low voltage (LV) power supply board. The transceiver board performs the frontend processing like transmit beamforming, control, analog signal conditioning and digital receive beamforming. The received beamformed data are directly transferred to a host PC via the Gigabit Ethernet interface for image formation, post-processing and display. The ASIC-based system developed can provide real-time B-mode imaging with a maximum frame rate of 102 fps with a field of view (FOV) of [Formula: see text]. These results indicate that the ASIC-based US imaging systems can provide better processing capability and performance.

Full-Duplex NOMA-Enabled Integrated Sensing and Communication: Joint Transmit and Receive Beamforming Optimization

Full-Duplex NOMA-Enabled Integrated Sensing and Communication: Joint Transmit and Receive Beamforming Optimization

Enhancing efficiency in spaceborne phased array systems: MVDR algorithm and FPGA integration

Digital Beamforming (DBF) has garnered significant attention within the space community, driven by the heightened flexibility offered by satellites equipped with active antennas for diverse applications like spaceborne synthetic aperture radar (SAR) systems and communication services. This paper presents a comprehensive exploration encompassing analysis, design, and implementation of a Minimum Variance Distortionless Response (MVDR) algorithm tailored for application in a Digital Beamforming Receiver system. The described system leverages the capabilities of the high-speed Analog to Digital Converter (ADC) device EV12AQ600, space-qualified, and the high-performance FPGA XCKU085. These components are seamlessly integrated into the EV12AQ60X-ADX-EVM evaluation board, thoughtfully provided by Teledyne e2v Semiconductors. The design methodology outlined herein is driven by the overarching objective to minimize FPGA resource utilization and power consumption for spaceborne phased array systems. This objective is chiefly met through the implementation of a systolic array structure adept at processing both real and complex input samples. This innovative approach results in a substantial reduction in allocated resources compared to conventional architectures. Furthermore, the design incorporates the use of the CORDIC algorithm to compute the inverse of the correlation matrix, obviating the need for square root and division operations. This strategic utilization of algorithms enhances the system's efficiency in terms of resource utilization, computational load, and processing time. To validate the anticipated behavior of the adaptive beamforming system, various radio frequency (RF) input signals are applied to the system, which is physically instantiated on the EV12AQ60X-ADX-EVM evaluation board. The experimental results affirm the efficacy of the proposed design, underscoring its suitability for spaceborne applications.

Antenna Selection and Receive Beamforming for Multi-Functional Sparse Linear Array via Consensus ADMM

Antenna Selection and Receive Beamforming for Multi-Functional Sparse Linear Array via Consensus ADMM

Arbitrary-Order Output Intercept Points of an Analog Receive Beamforming System

Arbitrary-Order Output Intercept Points of an Analog Receive Beamforming System

Joint Transmit and Receive Beamforming Design for DPC-Based MIMO DFRC Systems

This paper proposes an optimal beamforming strategy for a downlink multi-user multi-input–multi-output (MIMO) dual-function radar communication (DFRC) system with dirty paper coding (DPC) adopted at the transmitter. We aim to achieve the maximum weighted sum rate of communicating users while adhering to a predetermined transmit covariance constraint for radar performance assurance. To make the intended problem trackable, we leverage the equivalence of the weighted sum rate and the weighted minimum mean squared error (MMSE) to reframe the issue and devise a block coordinate descent (BCD) approach to iteratively calculate transmit and receive beamforming solutions. Through this methodology, we demonstrate that the optimal receive beamforming aligns with the traditional MMSE approach, whereas the optimal transmit beamforming design can be cast into a quadratic optimization problem defined on a complex Stiefel manifold. Based on the majorization–minimization (MM) method, an iterative algorithm is then developed to compute the optimal transmit beamforming design by solving a series of orthogonal Procrustes problems (OPPs) that admit closed-form optimal solutions. Numerical findings serve to validate the efficacy of our scheme. It is demonstrated that our approach can achieve at least 73% higher spectral efficiency than the existing methods in a high signal-to-noise ratio (SNR) regime.

A 16-Channel 3.1–25.5-GHz Phased-Array Receive Beamformer IC With Two Simultaneous Beams and 2.0–2.4-dB NF for C/X/Ku/Ka-Band SATCOM

A 16-Channel 3.1–25.5-GHz Phased-Array Receive Beamformer IC With Two Simultaneous Beams and 2.0–2.4-dB NF for <i>C</i>/<i>X</i>/<i>Ku</i>/<i>Ka</i>-Band SATCOM

A General Scheme of a Branch-and-Bound Approach for the Sensor Selection Problem in Near-Field Broadband Beamforming.

This paper is devoted to the sensor selection problem. A broadband receiver beamforming working in a near-field is considered. The system response should be as close as possible to the desired one, which is optimized in the sense of L2 norm. The problem considered is at least NP-hard. Therefore, the branch-and-bound algorithm is developed to solve the problem. The proposed approach is universal and can be applied not only to microphone arrays but also to antenna arrays; that is, the methodology for the generation of consecutive solutions can be applied to different types of sensor selection problems. Next, for a larger microphone array, an efficient metaheuristic algorithm is constructed. The algorithm implemented is a hybrid genetic algorithm based on the ITÖ process. Numerical experiments show that the proposed approach can be successfully applied to the sensor selection problem.

Analysis and Design of a Multiplex, Delay‐and‐Sum (MDAS) Beamformer Architecture to Implement a Fixed‐Focus Receive Beamformer for Portable Ultrasound Imaging Systems

A multiplex, delay‐and‐sum (MDAS) architecture is proposed to implement a fixed‐focus receive beamformer such as the first stage of the synthetic aperture sequential beamforming (P‐SASB) and synthetic transmit beams combined with the P‐SASB (STB‐P‐SASB) beamforming methods. The output image of this architecture has a resolution and contrast‐to‐noise ratio (CNR) almost similar to that of the delay‐and‐sum (DAS) architecture. In the analog part of this architecture, there is no need to use any analog memory and in the digital part, the need to use high‐speed memories and interpolation filter is eliminated. In this architecture for each input channel, the power consumption in the mixed‐signal part is increased by approximately 1.14 mW in comparison to that of the DAS architecture. On the other hand, due to the elimination of the power consumption related to the interpolation filter in the digital part, the total power consumption of the MDAS architecture increases by a maximum of 9.2% compared to the DAS architecture. Also, the silicon area required to implement the mixed‐signal part of the MDAS architecture when implementing the first stage of P‐SASB and STB‐P‐SASB beamforming methods is reduced by about 3 times and increased by a maximum of 25%, respectively, compared to that of the DAS architecture.

Transceiver Beamforming for Over-the-Air Computation in Massive MIMO Systems

This paper investigates the transmitter and receiver beamforming (TB and RB) for over-the-air computation (AirComp) in massive multiple-inputs and multiple-outputs (MIMO) systems. First, we propose a two-phase hybrid beamforming algorithm to design TB and hybrid RB. In the first phase, we adopt a projected gradient descent with momentum (PGDM) algorithm to search for the optimal fully-digital TB matrices. Compared with the benchmarks on the mean square error (MSE) performances, PGDM can achieve up to 5 dB gain in signal-to-noise ratio (SNR) with less algorithm execution time when fully-digital RB is assumed. In the second phase, we plug the TB matrices obtained in PGDM as well as the optimal baseband RB (BBRB) matrix into the MSE objective, and adopt gradient descent to search for the optimal radio-frequency RB (RFRB) matrix. Compared with the state-of-the-arts, the proposed two-phase algorithm reduces up to 30% of the algorithm execution time and 18% of the MSE. Second, we propose a statistical TB algorithm to reduce the communication overheads, in which TB completely depends on statistical channel state information (CSI) and thus does not rely on the feedback from the base station (BS). We prove that orthonormal matrices are asymptotically optimal for statistical TB when uncorrelated <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Rayleigh</i> channels are assumed and the number of receiving antennas approaches to infinity. For correlated channels, experimental results show that the proposed statistical TB can achieve about 5 dB gain in SNR compared with orthonormal matrices in terms of the MSE performance. Third, a large scale system analysis is made in this paper. As the number of the receiving antennas approaches to infinity, asymptotically optimal choices for TB and RB are provided, and upper bounds of MSE are derived in terms of the number of clients and receiving antennas. For hybrid RB, an upper bound of the squared distance between the optimal hybrid RB and the optimal fully-digital RB is also derived.

Joint Transmit and Receive Beamforming Design in Full-Duplex Integrated Sensing and Communications

Integrated sensing and communication (ISAC) has been envisioned as a solution to realize the sensing capability required for emerging applications in wireless networks. For a mono-static ISAC transceiver, as signal transmission durations are typically much longer than the radar echo round-trip times, the radar returns are drowned by the strong residual self interference (SI) from the transmitter, despite adopting sufficient SI cancellation techniques before digital domain - a phenomenon termed the echo-miss problem. A promising approach to tackle this problem involves the ISAC transceiver to be full-duplex (FD), and in this paper we jointly design the transmit and receive beamformers at the transceiver, transmit precoder at the uplink user, and receive combiner at the downlink user to simultaneously (a) maximize the uplink and downlink communication rate, (b) maximize the transmit and receive radar beampattern power at the target, and (c) suppress the residual SI. To solve this optimization problem, we proposed a penalty-based iterative algorithm. Numerical results illustrate that the proposed design can effectively achieve up to 60 dB digital-domain SI cancellation, a higher average sum-rate, and more accurate radar parameter estimation compared with previous ISAC FD studies.

Receive Beamforming Designed for Massive Multi-User MIMO Detection via Gaussian Belief Propagation

Receive Beamforming Designed for Massive Multi-User MIMO Detection via Gaussian Belief Propagation

Securing Multi-User Uplink Communications Against Mobile Aerial Eavesdropper via Sensing

In this paper, we propose a secure multi-user uplink communicaion scheme against a mobile aerial eavesdropper (AE) in Integrated Sensing and Communication (ISAC) systems, where the ISAC base station transmits radar signals to track and jam the AE. For tracking mobile AE, we adopt an extended Kalman filter technique to predict AE's motion state. Based on the tracking information we formulate an optimization problem to jointly design radar signal and receiver beamformer for improving the secrecy performance. To deal with the non-convex constraints and the coupled variables, we propose an alternating optimization based algorithm via iteratively solving a Fractional Programming (FP) problem and a Semidefinite Program (SDP) problem. Numerical results show that the proposed algorithm can achieve higher secrecy capacity and better fairness, compared to the state-of-the-art techniques.

Fully Integrated Electronic-Photonic Ultrasound Receiver Array for Endoscopic Applications in a Zero-Change 45-nm CMOS-SOI Process

This article presents the first fully integrated 2-D array of electronic-photonic ultrasound sensors targeting low-power miniaturized ultrasound probes for endoscopic applications. Fabricated in a zero-change 45-nm CMOS-silicon-on-insulator (SOI) technology, this 5.53 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\times$</tex-math> </inline-formula> 3.03 mm electronic-photonic system on chip (EPSoC) utilizes micro-ring resonators (MRRs) as ultrasound sensors instead of the traditional piezoelectric or capacitive micromachined transducers (PMUTs or CMUTs). The photonic nature of the sensor enables remoting of the power-hungry receive electronics outside the probe tip, thus lowering the power dissipation inside the human body. Moreover, it eliminates electrical cabling, replacing the bulky micro-coax cables with thinner optic fibers. This EPSoC also reduces fiber count by 8 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\times$</tex-math> </inline-formula> with zero power and area overhead by performing wavelength division multiplexed interrogation of MRR sensors coupled onto the same waveguide in lieu of sub-array beamforming or in-pixel digitization. Leveraging the monolithic integration of photonic devices with CMOS circuitry, a complete receiver (RX) unit is built right next to the sensor MRRs, including a programmable gain transimpedance amplifier (TIA) and background current cancellation digital-to-analog converters ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$I_{\text{DAC}}$</tex-math> </inline-formula> s), which allow for a sensor operating range of 74 dB. A 9-bit SAR ADC performs on-chip A/D conversion making for a self-contained endoscopic ultrasound receiver system. The photonic sensing element demonstrates 7.3 mV/kPa sensitivity while consuming 0.43 mW of power and occupying 0.01 mm of area. The functionality of the fabricated chip has been demonstrated in ultrasonic receiver beamforming experiments.

Design and Development of Multibeam Antenna Technologies for 5G Wireless Communications

Multibeam antenna (MBA) systems operating in the millimeter-wave frequency bands have drawn significant attention from researchers and are being effectively studied due to the demanding system needs for the fifth-generation (5G) wireless communication systems and the drastic spectrum scarcity at the existing cellular frequency range. To enable a greater transmission speed, an enhanced signal-to-interference-plus-noise ratio, an enhanced spectral and energy performance, and flexible beam shaping, they serve as the primary antenna technology. They offer tremendous potential for serving as the crucial infrastructure for facilitating beamforming and massive multiple-input multiple-output (MIMO) which uplift the 5G. To achieve this, a novel beamforming design and optimization approach based on the Convex Time Modulated Particle Swarm Optimization (CTM-PSO) algorithm is suggested for 5G communication networks, offering multiple concurrent transceivers to support efficient beamformed interactions whereas a second beam concurrently detects the atmosphere around the base-station. The suggested beamforming method combines the optimization of the transmitter and receiver beamforming weights to increase sensor performance, reduce potential intervention resulting from the communication beams, and ensure the communications link's target beamforming gains. Comprehensive numerical assessments are used to evaluate the effectiveness of the recommended method, showing that it may provide significant improvements over more conventional beamforming methods.

Impact of Polarization on Distributed Optical Beamforming

In this letter, we propose the concept of distributed optical beamforming and its feasibility requirements. We quantify the importance of polarization beamforming among the beams for maximized beamforming. As a first step towards distributed polarization beamforming (DPolB), in this work we consider coplanar sources and receiver for beamforming and demonstrate the critical requirement of polarization alignment for maximized beamforming gain. We determine theoretically and verify via simulations the optimal polarization angle at the sources such that the electromagnetic waves interfere constructively at the receiver. Subsequently, we propose a novel method for automated polarization beamforming of multiple optical beams independent of source locations. Performance of the proposed DPolB is analytically captured in terms of average beamforming gain and verified using simulations. We also verify that the reduction in gain caused by slight deviation from coplanarity is not significant.

Joint Client Selection and Receive Beamforming for Over-the-Air Federated Learning With Energy Harvesting

Federated learning (FL) is a well-regarded distributed machine learning technology that leverages local computing resources while protecting privacy. The over-the-air (OTA) computation has been adopted for FL to prevent excessive consumption of communication resources by employing the superposition nature of wireless waveform. Meanwhile, energy harvesting technology can relieve the energy constraint of clients and enable durable computation for FL. However, few of the existing works on OTA FL have considered jointly performing client selection and receive beamforming optimization with energy harvesting clients. The objective of this work is to address this issue to improve the learning performance of OTA FL. Specifically, we first derive the expression of the optimality gap regarding client selection and receive beamforming design. Then, to minimize the optimality gap, a mixed-integer nonlinear programming (MINLP) problem is formulated and decomposed into two sub-problems. Next, the semidefinite relaxation method and the channel-energy-data (CED)-based method are developed to optimize the receive beamforming sub-problem and client selection sub-problem iteratively. One alternative optimization method is proposed to deal with the decoupled sub-problems for obtaining the solutions to the original MINLP problem. Our simulation results demonstrate that the proposed solution is superior to the other comparison schemes in various parameter settings.

Max-Min Rate Optimization for Uplink IRS-NOMA With Receive Beamforming

This letter addresses an intelligent reflecting surface (IRS) to the uplink nonorthogonal multiple access (NOMA) served by a multiantenna receiver for effective data collection from massive devices. We aim to achieve max-min fairness of the network by optimizing receive beamforming, IRS reflection, and transmit power allocation (PA) of the devices. For this purpose, first, we design a block coordinate descent (BCD) algorithm that reduces the complexity of a conventional IRS reflection optimization. Next, we design a nonlinear optimization (NLO) problem solvable with the limited-memory Broyden-Fletcher-Goldfarb-Shanno bounded (L-BFGS-B) algorithm, which is renowned for handling large-scale problems, to cope with large IRS elements and devices. The problem is formed with a smooth but complex objective function that depends on the IRS phase shift and PA vectors for which the gradient is derived in a computationally efficient form. The results reveal that the proposed BCD and proposed NLO with the L-BFGS-B outperform the conventional BCD in performance and complexity, where the NLO approach offers a substantial complexity reduction.

Beamformer Design and Optimization for Joint Communication and Full-Duplex Sensing at mm-Waves

In this article, we study the joint communication and sensing (JCAS) paradigm in the context of millimeter-wave (mm-wave) mobile communication networks. We specifically address the JCAS challenges stemming from the full-duplex operation in monostatic orthogonal frequency-division multiplexing (OFDM) radars and from the co-existence of multiple simultaneous beams for communications and sensing purposes. To this end, we first formulate and solve beamforming optimization problems for hybrid beamforming based multiuser multiple-input and multiple-output JCAS systems. The cost function to be maximized is the beamformed power at the sensing direction while constraining the beamformed power at the communications directions, suppressing interuser interference and cancelling full-duplexing related self-interference (SI). We then also propose new transmitter and receiver beamforming solutions for purely analog beamforming based JCAS systems that maximize the beamforming gain at the sensing direction while controlling the beamformed power at the communications direction(s), cancelling the SI as well as eliminating the potential reflection from the communication direction and optimizing the combined radar pattern (CRP). Both closed-form and numerical optimization based formulations are provided. We analyze and evaluate the performance through extensive numerical experiments, and show that substantial gains and benefits in terms of radar transmit gain, CRP, and SI suppression can be achieved with the proposed beamforming methods.

A Robust IRS-Aided Wireless Information Surveillance Design With Bounded Channel Errors

This letter studies an intelligent reflecting surface (IRS)-aided wireless information surveillance system, in which the IRS is leveraged to help the legitimate receiver (LR) intercept the information transmitted from a suspicious transmitter (ST) to a suspicious user (SU). In particular, we consider the challenging scenario where all involved channels are not perfectly known at the LR. We investigate the joint design of the receiver beamformer at the LR and the phase shifts at the IRS for maximization of the worst-case information monitoring rate (WCIMR) by considering the deterministically bounded errors of channel state information (CSI). To solve the resulting non-convex optimization problem, a robust algorithm is proposed based on the general S-procedure, the general sign-definiteness lemma, the penalty-based and successive convex approximation (SCA) techniques. Simulation results demonstrate the effectiveness of the proposed algorithm and also show that the IRS can significantly improve the WCIMR compared to conventional architectures without IRS.