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Architecture, Urbanism and Building Science

Super-Resolution Channel Estimation for Arbitrary Arrays in Hybrid Millimeter-Wave Massive MIMO Systems

This paper develops efficient channel estimation techniques for millimeter-wave (mmWave) massive multiple-input multiple-output (MIMO) systems under practical hardware limitations, including an arbitrary array geometry and a hybrid hardware structure. Taking on an angle-based approach, this work adopts a generalized array manifold separation approach via Jacobi-Anger approximation, which transforms a non-ideal, non-uniform array manifold into a virtual array domain with a desired uniform geometric structure to facilitate super-resolution angle estimation and channel acquisition. Accordingly, structure-based optimization techniques are developed to effectively estimate both the channel covariance and the instantaneous channel state information (CSI) within a short sensing time. The different time-varying scales of channel path angles versus path gains are capitalized to design a two-step CSI estimation scheme that can quickly sense fading channels. Theoretical results are provided on the fundamental limits of the proposed technique in terms of sample efficiency. For computational efficiency, a fast iterative algorithm is developed via the alternating direction method of multipliers. Other related issues such as spurious-peak cancellation in non-uniform linear arrays and extensions to higher-dimensional cases are also discussed. Simulations testify the effectiveness of the proposed approaches in hybrid mmWave massive MIMO systems with arbitrary arrays.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Circuits and System

Low-Complexity Gridless 2D Harmonic Retrieval via Decoupled-ANM Covariance Reconstruction

This paper aims at developing low-complexity solutions for super-resolution two-dimensional (2D) harmonic retrieval via covariance reconstruction. Given the collected sample covariance, a novel gridless compressed sensing approach is designed based on the atomic norm minimization (ANM) technique. The key is to perform a redundancy reduction (RR) transformation that effectively reduces the large problem size at hand, without loss of useful frequency information. For uncorrelated sources, the transformed 2D covariance matrices in the RR domain retain a salient structure, which permits a sparse representation over a matrix-form atom set with decoupled 1D frequency components. Accordingly, the decoupled ANM (DANM) framework can be applied for super-resolution 2D frequency estimation, at low computational complexity on the same order of the 1D case. An analysis of the complexity reduction of the proposed RR-D-ANM compared with benchmark methods is provided as well, which is verified by our simulation resultsGreen Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Circuits and System

Efficient Angle Estimation for MIMO Systems via Redundancy Reduction Representation

This paper proposes an efficient direction of departure (DOD) and direction of arrival (DOA) estimation method for multi-input multi-output (MIMO) systems. For uncorrelated scenarios, the redundancy of the covariance matrix is first exploited by establishing its concise representation through redundancy reduction, which transforms the original large-size covariance matrix into a smaller-size matrix without loss of useful angle information. Then, the resulting transformed matrix, which retains a salient structure, permits efficient two-dimensional (2D) angle estimators working on a reduced-size problem for DOD and DOA estimation. Compared with conventional subspace-based methods, the proposed method incorporating an appropriate 2D angle estimator is more computationally efficient and can achieve higher estimation accuracy for small numbers of snapshots and low signal-to-noise ratios, which are verified by simulation results.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Circuits and System

Efficient Super-Resolution Two-Dimensional Harmonic Retrieval Via Enhanced Low-Rank Structured Covariance Reconstruction

This paper develops an enhanced low-rank structured covariance reconstruction (LRSCR) method based on the decoupled atomic norm minimization (D-ANM), for super-resolution two-dimensional (2D) harmonic retrieval with multiple measurement vectors. This LRSCR-D-ANM approach exploits a potential structure hidden in the covariance by transferring the basic LRSCR to an efficient D-ANM formulation, which permits a sparse representation over a matrix-form atom set with decoupled 1D frequency components. The new LRSCR-D-ANM method builds upon the existence of a generalized Vandermonde decomposition of its solution, which otherwise cannot be guaranteed by the basic LRSCR unless a very conservative condition holds. Further, a low-complexity solution of the LRSCR-D-ANM is provided for fast implementation with negligible performance loss. Simulation results verify the advantages of the proposed LRSCR-D-ANM over the basic LRSCR, in terms of the wider applicability and the lower complexity.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Circuits and System

Super-Resolution Harmonic Retrieval of Non-Circular Signals

This paper proposes a super-resolution harmonic retrieval method for uncorrelated strictly non-circular signals, whose covariance and pseudo-covariance present Toeplitz and Hankel structures, respectively. Accordingly, the augmented covariance matrix constructed by the covariance and pseudo-covariance matrices is not only low rank but also jointly Toeplitz-Hankel structured. To efficiently exploit such a desired structure for high estimation accuracy, we develop a low-rank Toeplitz-Hankel covariance reconstruction (LRTHCR) solution employed over the augmented covariance matrix. Further, we design a fitting error constraint to flexibly implement the LRTHCR algorithm without knowing the noise statistics. In addition, performance analysis is provided for the proposed LRTHCR in practical settings. Simulation results reveal that the LRTHCR outperforms the benchmark methods in terms of lower estimation errors.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Signal Processing System

Efficient Super-Resolution Two-Dimensional Harmonic Retrieval with Multiple Measurement Vectors

This paper develops an efficient solution for super-resolution two-dimensional (2D) harmonic retrieval from multiple measurement vectors (MMV). Given the sample covariance matrix constructed from the MMV, a gridless compressed sensing approach is proposed based on the atomic norm minimization (ANM). In the approach, our key step is to perform a redundancy reduction (RR) transformation that effectively reduces the large problem size at hand, without loss of useful frequency information. For uncorrelated sources, the transformed 2D covariance matrices in the RR domain retain a salient structure, which permits a sparse representation over a matrix-form atom set with decoupled 1D frequency components. Accordingly, the decoupled ANM (D-ANM) framework can be applied for super-resolution 2D frequency estimation. Moreover, the resulting RR-enabled D-ANM technique, termed RR-D-ANM, further allows an efficient relaxation under certain conditions, which leads to low computational complexity of the same order as the 1D case. Simulation results verify the advantages of our solutions over benchmark methods, in terms of higher computational efficiency and detectability for 2D harmonic retrieval.taverneCircuits and System

中國現代企業經營型態- 以劉鴻生企業為例的個案研究1911-1949

[[abstract]]本論文之研究目的，在探討劉鴻生企業的整體發展，研究其在企業經營型態上具有何 種特色，觀察政治、經濟、社會等因素對其經營型態的影響，透過對此個案的深入分 析，找出影響二十世紀初期中國現代企業之發展及其經營型態的內外在因素，由此更 進一步檢視中國企業現代化之癥結所在。 資料來源方面，以劉鴻生企業史料集，實業家劉鴻生傳略，以及當代各種期刊，如東 方雜誌、上海總商會月報、工商半月刊、申報月刊、銀行週報、經濟周報、金融週報 ，經濟導報等為主要史料。研究方法則以史實為基礎，運用個體經濟學、企業管理學 的概念，對劉氏企業的發展過程加以探討和分析。 研究結果指出，劉氏企業在中國現代企業發展史上的代表性：第一，由商業資本轉為 工業資本；第二，與帝國主義勢力的結合與對抗；第三，國內同業的競爭與合作；第 四，國家資本、官僚資本與私人資本的衝突性。

[[alternative]]Biomechanical analysis of the elite Taiwan high jumpers in the fosbury flop

[[abstract]]本實驗是使用兩部高速電子攝影機，及兩部VHS 攝影機，作同步拍攝國內民國81年度 男子排名前十傑中的四位優秀選手，進行三度空間的運動學分析，並利用KISTLER 測 力板測量起跳時的垂直力量與垂直衡量，了解國內優秀選手在背向高式跳高中，跳過 兩公尺時的運動學及動力學的變化及其關係。 本研究經過師大體育研究所運動生物力學實驗室，VIDEO-3D影帶分析系統，處理分析 所得資料，得到的結論如下： 1 、四位選手助跑最後第二步步幅與最後一步步幅、速度、角度，均比國外一流選手 為小為慢，尤其最後一步的速度比國外一流選手差距更大，應針對這點加以改進。 2 、在跳高運動，每跳一次花費身體體重的2到7倍之多的垂直力量，因此必須增加選 手身體全身的肌力，尤其是腿部及腳部的肌力。 3 、四位選手起跳踏地時身體重心高度(HO)；起跳時起跳腳離地瞬間的身體重心高度 (HI)與起跳時身體重心飛程的高度皆比國外一流跳高選手為低，尤其是離地後身體飛 程的重心高度高度(H2)比國外一流選手低最多，是要加強的重點。而四位選手從起跳 時達到最高點身體重心與橫竿距離較接近，顯示過竿技術較佳。 4 、四位選手起跳水平速度、垂直速度與起跳時合速度，三種速度均比國外一流選手 慢。所以四位選手應該特別加強速度訓練。 5 、四位選手的起跳水平角度比國外一流選手大，而起跳的拋射角度，比國外優秀選 手還小。如果水平角度過大可能造成垂直拋射角度不利。 6 、四位選手的起跳腳在踏地時膝關節的角度比國外一流選手較小。而起跳離地時的 膝關節角度，與國外一流選手幾乎相同。至於起跳時前導腿抬的高度與水平所成的角 度平均為-8度，顯示四位優秀選手的前導腿抬的高度都不過。 7 、高四位選手助跑最後第二步至最後一步到起跳踏地或離地時的內傾角度，均比國 外一流選手為小。尤其在起跳踏地時的內傾角現象較為明顯。關於助跑最後第二步至 最後一步踏地或離地時的前傾後傾角度均比國外一流選手較小，尤其在起跳踏地時的 前傾後傾角度，有明顯較內現象。 8 、四位選手起跳點離竿距離平均為93公分，於國外一流選手離橫竿距離的80到140 公分之間。顯示四位選手的起跳點離竿距離尚可。 9 、四位選手中，有林明宏、歐建友、蔡金鋼等三位選手的動作結構較接近速度型的 跳法。而廖學松的動作結構較類似瞬發力型的跳法。

桃園台地都市體系之研究

[[abstract]]一個區域內，各大小中心聚落具有商品和服務交換的機能和其影響的範圍存在，這 種相互依存的關係，形成了階層的關係，也就是所謂都市體系。不過由於區域內， 交通運輸之改善，工商業之發展，生活水準之提高，人口之增減等使每一個聚落的 機能有所改變，使其影響範圍和區內的都市體系將有所調整。 桃園台地在大台北市的邊緣地區，因台北市過度發展，許多工廠、學校、機關及其 他公共設施紛紛遷入本區，使桃園台地負擔疏散台北市之人口、產業過度發展的使 命。故本區的工廠增多、人口增加、商業機能也加強了，此可由各聚落階層的改變 ，影響圈的變貌，商品的自給率看出梗概。 一、桃園台地都市之階層為桃園、中壢為第四階層都市；楊梅、大溪為第三階層都 市；龜山、八德、平鎮、龍潭等為第二階層都市；大園、蘆竹、新屋、觀音等 為第一階層都市。 二、初級品購物，因交通愈來愈方便，各鄉鎮銷售系統漸趨完備，在各地普遍出現 ，故初級品的自給率提高，只有平鎮到中壢購買百分比相當高，此乃二者連成 一體之故。中級品購物和初級品購物類似，但因品質差異大，大部分仍在本區 的桃園、中壢購買。高級品購物，各鄉鎮不能提供，到桃園、中壢購買的百分 比更高，一部分也到台北市購買。 三、通勤工作，由於本區工廠多，通勤現象尚屬頻繁，至於通勤到台北工作，除主 要幹道和鐵路沿線都市之桃園、中壢、楊梅、湖口、龜山增加外，其餘各鄉鎮 均減少，顯示交通發展對通勤工作的影響。 四、本區娛樂（看電影）的設施和購物相似，較落後的鄉村，因無電影院的設施， 必須到中壢、桃園觀賞，但到其他地區則很少。至於醫療；本區醫院設施尚嫌 不足，到台北市醫療的現象尚為頻繁。