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arXiv · 2310.20198

Structured Two-Stage True-Time-Delay Array Codebook Design for Multi-User Data Communication

Aditya Wadaskar·Ding Zhao·Ibrahim Pehlivan·Danijela Cabric
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Abstract

Wideband millimeter-wave and terahertz (THz) systems can facilitate simultaneous data communication with multiple spatially separated users. It is desirable to orthogonalize users across sub-bands by deploying frequency-dependent beams with a sub-band-specific spatial response. True-Time-Delay (TTD) antenna arrays are a promising wideband architecture to implement sub-band-specific dispersion of beams across space using a single radio frequency (RF) chain. This paper proposes a structured design of analog TTD codebooks to generate beams that exhibit quantized sub-band-to-angle mapping. We introduce a structured Staircase TTD codebook and analyze the frequency-spatial behaviour of the resulting beam patterns. We develop the closed-form two-stage design of the proposed codebook to achieve the desired sub-band-specific beams and evaluate their performance in multi-user communication networks.

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Aditya Wadaskar, Ding Zhao, Ibrahim Pehlivan, Danijela Cabric. 2023-11-15. Structured Two-Stage True-Time-Delay Array Codebook Design for Multi-User Data Communication. https://arxiv.org/abs/2310.20198

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