- 标题
- 摘要
- 关键词
- 实验方案
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Non-Uniform Quantization Codebook Based Hybrid Precoding to Reduce Feedback Overhead in Millimeter Wave MIMO Systems
摘要： In this paper, we propose two non-uniform quantization (NUQ) codebook based hybrid precoding schemes for two main hybrid precoding implementations, i.e., the full-connected structure and the sub-connected structure, to reduce the feedback overhead in millimeter wave single user multiple-input multiple-output (SU-MIMO) systems. Specifically, we firstly group the angles of the arrive/departure (AOAs/AODs) of the scattering paths into several spatial lobes by exploiting the sparseness property of the millimeter wave in the angular domain, which divides the total angular domain into effective spatial lobes' coverage angles and ineffective coverage angles. Then, we map the quantization bits non-uniformly to different coverage angles and construct NUQ codebooks, where high numbers of quantization bits are employed for the effective coverage angles to quantize AoAs/AoDs and zero quantization bit is employed for ineffective coverage angles. Finally, two low-complexity hybrid analog/digital precoding schemes are proposed that utilize the NUQ codebooks. Simulation results demonstrate that, the proposed two NUQ codebook based hybrid precoding schemes achieve near-optimal spectral efficiencies and show the superiority in reducing the feedback overhead compared with the uniform quantization codebook based works.
关键词： feedback overhead,non-uniform quantization,spatial lobe,Millimeter wave communication,hybrid precoding
更新于2025-09-23 15:23:52
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P-OMP-IR ALGORITHM FOR HYBRID PRECODING IN MILLIMETER WAVE MIMO SYSTEMS
摘要： This paper presents a P-OMP-IR algorithm for the hybrid precoding problem in millimeter wave (mm-Wave) multiple-input multiple-output (MIMO) systems. In the proposed approach, the digital precoding matrix is updated via the orthogonal matching pursuit (OMP) method, and the analog precoding matrix is re?ned column by column using the dominant singular value and corresponding singular vectors of a residual matrix successively. During the re?ning phase of the analog precoding matrix, an extended power method is designed to calculate the dominant singular value and the corresponding left and right singular vectors, which is able to reduce the computational complexity signi?cantly. Simulation results show that the proposed algorithm can not only reduce the residual of the hybrid precoder e?ectively, but also improve the spectral e?ciency consistently.
关键词： millimeter wave,MIMO systems,orthogonal matching pursuit,P-OMP-IR algorithm,spectral efficiency,hybrid precoding
更新于2025-09-23 15:21:01
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Hybrid Precoding for Wideband Millimeter-Wave Systems with Finite Resolution Phase Shifters
摘要： In this paper, we study the hybrid analog-digital precoding for OFDM based-wideband millimeter wave (mmwave) communication systems. Since the analog precoding matrix is performed in the time domain and used for the entire bandwidth while the digital precoding matrices are performed on a per-subcarrier basis, the resulting wideband hybrid precoding problem becomes very complicated. Moreover, in practice phase shifter (PS) usually has only finite resolution, which brings more difficulties. To solve the resulting difficult problem, we propose an efficient algorithm by leveraging the penalty decomposition method. Simulation results are finally provided to confirm the effectiveness and superiority of the proposed algorithm and show the performance improvement than the existing algorithm.
关键词： finite resolution phase shifter,wideband hybrid precoding,decomposition method,Wideband millimeter wave communication
更新于2025-09-23 15:21:01
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Hybrid Precoding with Partially Connected Structure for mmWave Massive MIMO OFDM: A Parallel Framework and Feasibility Analysis
摘要： Hybrid precoding, a combination of digital and analog precoding, is an alternative to traditional precoding methods in massive MIMO systems with large number of antenna elements and has shown promising results recently. In this work, we implement a parallel framework to make hybrid precoding competitive in fast-fading environments. A low-complexity algorithm which exploits the block diagonal phase only nature of the analog precoder in a partially connected structure is proposed to arrive at a hybrid precoding solution for a multi-carrier single-user system using orthogonal frequency division multiplexing (OFDM). The original problem is broken down into two subproblems of finding the magnitude and the phase components which are solved independently. A per-RF chain power constraint is introduced instead of the sum power constraint over all antennas which is much more practical in real systems. An alternating version of the same algorithm is proposed for increased spectral-efficiency gains. Complexity and run-time analysis demonstrate the advantage of the proposed algorithm over existing hybrid precoding schemes for partially connected structure in an OFDM setting. Simulation results reveal certain insights about the partially connected structure and the trade-offs that have to be made to make it workable in a real wideband system.
关键词： partially connected structure,mmWave,massive MIMO,per-RF chain power constraint,Hybrid precoding,OFDM
更新于2025-09-10 09:29:36
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[IEEE 2018 IEEE 5G World Forum (5GWF) - Silicon Valley, CA (2018.7.9-2018.7.11)] 2018 IEEE 5G World Forum (5GWF) - Millimeter Wave Massive MIMO with Alamouti Code and Imperfect Channel State Information
摘要： Massive MIMO is one of the technologies considered in 5G to provide a much higher capacity without requiring more wireless spectrum. Because of the congestion in the radio frequency spectrum below 6 GHz, the millimeter Wave (mmWave) band has increasingly become more attractive to researchers since it offers a much larger unused bandwidth. However, the higher path loss at mmWave frequencies and the poor scattering nature of the mmWave channel (fewer paths exist) represent a challenge for communications. A hybrid beamforming technique with large antenna arrays and the Alamouti coding scheme are used in this paper to improve the performance of a single-user mmWave massive MIMO system. When perfect Channel State Information (CSI) is not available at the Base Station (BS), computer simulations have shown that a gain of 20 dB or more can be achieved by using the Alamouti code compared to the system with hybrid beamforming only, and more importantly, the error probability does not level off.
关键词： hybrid precoding and combining,mmWave communication,Massive MIMO,Alamouti Code
更新于2025-09-09 09:28:46
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[IEEE 2018 10th International Conference on Wireless Communications and Signal Processing (WCSP) - Hangzhou, China (2018.10.18-2018.10.20)] 2018 10th International Conference on Wireless Communications and Signal Processing (WCSP) - Achievable Rate of Indoor THz Communication Systems with Finite-Bit ADCs
摘要： In this paper, the achievable rate of the downlink terahertz (THz) communication systems equipped with finite-bit analog-to-digital converters (ADCs) at user sides is investigated. Considering the array of subarray antenna structure, the hybrid precoding with the maximum ratio transmission (MRT) and zero-forcing (ZF) precoding are applied at the baseband. The closed-form expression of the lower bound of the achievable rate is derived when the number of subarray antennas goes to infinity. It is shown that the coarse quantization distortion cannot be ignored in large antenna subarray regime. On the other hand, the rate loss caused by the phase uncertainties can be negligible in large subarray antenna regime. Overall, the impact of quantized receivers on the performance of indoor THz communication systems is characterized.
关键词： finite-bit ADCs,hybrid precoding,Terahertz communication,phase uncertainties,achievable rate
更新于2025-09-04 15:30:14
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Hybrid Beamforming Design for Full-Duplex Millimeter Wave Communication
摘要： Harnessing the abundant availability of spectral resources at millimeter wave (mmWave) frequencies is an attractive solution to meet the escalating data rate demands. Additionally, it has been shown that full-duplex (FD) communication has the potential of doubling the bandwidth efficiency. However, the presence of significant residual self-interference (SI), which is especially more pronounced at mmWave frequencies because of the non-linearities in the hardware components, erodes the full potential of FD in practice. Conventionally, the residual SI is canceled in the baseband using digital processing with the aid of a transmit precoder. In this work, we propose a hybrid beamforming design for FD mmWave communications, where the SI is canceled by the joint design of beamformer weights at the radio-frequency (RF) and the precoder as well as combiner in the baseband. Our proposed design preserves the dimensions of the transmit signal, while suppressing the SI. We demonstrate that our joint design is capable of reducing the SI by upto 30 dB, hence performing similarly to the interference-free FD system while being computationally efficient. Our simulation results show that the proposed design significantly outperforms eigen-beamforming.
关键词： Beamforming,Millimeter Wave,Hybrid Precoding,MIMO,Full-Duplex
更新于2025-09-04 15:30:14