In order to efficiently cope with the high throughput, reliability, heterogeneity of Quality-of-Service (QoS), and massive connectivity requirements future 6G multi-antenna wireless networks, multiple access multiuser communication system design need depart from conventional interference management strategies, namely fully treat as noise (as commonly used in 4G/5G, MU-MIMO, CoMP, Massive MIMO, millimetre wave MIMO) decode Non-Orthogonal Multiple Access, NOMA). This paper is dedicated theory...

Localization for mobile devices is drawing increasing interest from both industry and academia as location-based services spring up in recent years. For rich scattering environments, such urban areas indoor corridors, fingerprint-based localization techniques are very promising. In this paper, we propose a single-site method massive multiple-input multiple-output (MIMO) orthogonal frequency-division multiplexing (OFDM) systems. A new angle delay channel power matrix fingerprint extracted...

Heterogenous networks and massive MIMO can significantly enhance spectral energy efficiencies of wireless have recently attracted lots attention. In this letter, we investigate joint user association spectrum allocation to further improve efficiency for enabled heterogeneous with full-duplex backhauls. The optimization problem is formulated as a mixed-integer nonlinear programming problem, therefore, nonconvex combinational. To solve the efficiently, original divided into two subproblems...

Rate-Splitting Multiple Access (RSMA) is an emerging flexible, robust and powerful multiple access scheme for downlink multi-antenna wireless networks. RSMA relies on (RS) strategies at the transmitter Successive Interference Cancellation (SIC) receivers, has unique ability to partially decode interference treat as noise so softly bridge two extremes of fully decoding (as in Non-Orthogonal Access, NOMA) treating Space Division SDMA or Multi-User Multiple-Input Multiple-Output, MU-MIMO). been...

In this letter, a compact dual-band dual-mode substrate integrated waveguide (SIW) balanced band-pass filter (BPF) with intrinsic common-mode (CM) suppression is designed by using single perturbed SIW circular cavity. The vias and slot perturbations are introduced to tune the resonant modes TE <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">010</sub> , xmlns:xlink="http://www.w3.org/1999/xlink">110</sub> (a pair of degenerate modes),...

Two-stage precoding is a promising transmission strategy for multi-user frequency division duplex (FDD) massive multiple-input multiple-output (MIMO) systems due to its large multiplexing gain with overhead reduction in both downlink channel estimation and state information (CSI) feedback. The performance of existing two-stage schemes mainly depends on appropriate selection clustering the users, which sometimes difficult realize realistic scenario limited number users having different...

Recently, the concept of holographic multiple-input multiple-output (MIMO) is emerging as one promising technologies beyond massive MIMO. Many challenges need to be addressed bring this novel idea into practice, including electromagnetic (EM)-compliant channel modeling and accurate performance evaluation. In paper, an EM-compliant model proposed for MIMO systems, which able both characteristics propagation non-ideal factors caused by mutual coupling at transceivers, antenna pattern...

In this paper, we address the problem of distributed angle estimation in wireless sensor localization system. Given that practical limitations on size and cost, i.e., anchor node cannot equip a complicated antenna or array, devise an alternative measure based fixed-spacing two-antenna equipment. Through multiple frequencies tuning, virtual non-uniform linear called synthetic array (MFSA), can be rebuilt independently at each node. We first provide theory unambiguity conditions for such then...

Massive multiple-input multiple-output (MIMO) systems have attracted extensive attention recently due to their potentials provide high system capacity. To obtain the benefits of massive MIMO systems, channel state information (CSI) at transmitter is essential. The overhead traditional estimation and feedback scheme for downlink makes frequency division duplexing (FDD) impractical. Compressive sensing (CS) a potential way alleviate problem. In this paper, we mainly focus on CS- based design....

In this paper, we investigate the quantization and feedback of downlink spatial covariance matrix for massive multiple-input multiple-output (MIMO) systems with cascaded precoding. Massive MIMO has gained a lot attention recently because its ability to significantly improve network performance. To reduce overhead channel estimation uplink in frequency-division duplex systems, precoding been used convert high-dimensional physical channels into low-dimensional effective channels. For...

Two-stage precoding is a promising transmission strategy for frequency-division duplex (FDD) massive multiple-input multiple-output (MIMO) systems due to its large multiplexing gain with significant overhead reduction in both downlink training and feedback. In this paper, we propose new agglomerative clustering method significantly simplify the user process. order suppress residual inter-cluster interference realistic two-stage transmission, an average signal-to-leakage-plus-noise ratio...

Optical axis pointing accuracy is an important index of airborne electro-optical (EO) platforms. In this work, we aim to correct the optical angle EO platform by digital compensation. First, a basic parameter model (BPM) error with clear physical significance established analyzing structure and source platform. Then, suppress nonlinear factors in error, propose improved algorithm semi-parametric regression based on BPM. Numerical simulation analysis shows that inherits advantages BPM, such...

This paper proposes a novel low power multiplierless radix-4 single-path delay commutator (R4SDC) FFT processor architecture for wireless LAN (IEEE 802.11 standard) applications, where short are utilised in the implementation of physical layer. The uses shift and addition operations to realize complex multiplications. By combining new architecture, butterfly architectures with this approach, resulting savings around 19% 35% 64-point 16-point respectively, as compared conventional based on...

This paper proposes two novel parallel-pipelined FFT architectures, based on multiplier-less implementation, targeting wireless communication applications, such as IEEE 802.11 baseband chip and MC-CDMA receiver. The proposed architectures have the advantages of high throughput power efficiency. architecture uses shift addition operations to realize complex multiplications. By combining a new commutator architecture, low butterfly with this approach, resulting area savings are up 31% 20%...

Abstract Heat generation mechanism in processes of ultrasonic welding plastics was not fully solved. Experiment results showed that increasing the amplitude increased energy dissipated with exception low amplitudes, but no detailed analysis can be found explaining this problem. This study proposed to investigate heat-generating such a condition new physically based model by solving N-S equations. The mean temperature profiles and final patterns are well agreed previous researches. predicted...

In this article, we investigate device-to-device (D2D) communication-enabled user cooperation in massive multiple-input multiple-output (MIMO) systems. frequency-division duplexing MIMO systems, cascaded precoding has been adopted to reduce the overhead of channel estimation and limited feedback. The inner precoder depends on spatial covariance matrix can be same for users that are close each other. When other, high-quality D2D links expected among form a virtual receiver via links. Since...

This paper proposes a low power commutator architecture for the implementation of radix-4 based pipelined fast Fourier transform processor. The is on dual port RAM blocks and exploits interconnection topology among these implementation. presents architecture, describes design methodology evaluation environment, provides results showing that new achieves up to 58% saving 256-point 128-point FFTs as compared previous architectures.

Fingerprint techniques are promising localization strategies in rich scattering environments, such as urban areas and indoor corridors. However, most existing approaches rely on multiple base station (BS) cooperation suffer from multipath propagation. In this paper, we propose a fingerprint based single-site method for massive multiple-input multiple-output (MIMO) orthogonal frequency-division multiplexing (OFDM) systems. The new angle delay channel power matrix (ADCPM) is extracted...

In order to improve the target localization accuracy based on airborne electro-optical payload, a novel passive scheme is proposed. Firstly, cross algorithm according collinear equation derived. And then improved by repeatedly measuring same present, which can suppress effect of measurement error. The experimental results show that up 9.3m when aircraft flying in 800m. This method effectively precision localization, and it has important practical value.

In frequency-division duplexing massive multiple-input multiple-output (MIMO) systems, cascaded precoding can convert the high-dimensional physical channel into a low-dimensional effective channel, such that traditional estimation and limited feedback be used. The inner precoder in depends on spatial covariance matrix of MIMO channel. If users are close to each other, they may share same because similar surrounding environments will result matrix. this case, user cooperation achieved among...

We present a localization system based on phase measurement for wireless sensor networks. The features at least 3 anchor nodes with known locations. broadcast synchronized reference signal to the location-unknown user nodes. measure relative offset of signals from different anchors, and indicates distance between anchors. can be utilized by hyperbolic algorithm, which 2-D coordinates all efficiently calculated node itself. advantage proposed method is that itself conducts ranging in...