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arXiv · 2308.11268

Orthogonal Constant-Amplitude Sequence Families for System Parameter Identification in Spectrally Compact OFDM

Shih-Hao Lu·Char-Dir Chung·Wei-Chang Chen·Ping-Feng Tsou
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Abstract

In rectangularly-pulsed orthogonal frequency division multiplexing (OFDM) systems, constant-amplitude (CA) sequences are desirable to construct preamble/pilot waveforms to facilitate system parameter identification (SPI). Orthogonal CA sequences are generally preferred in various SPI applications like random-access channel identification. However, the number of conventional orthogonal CA sequences (e.g., Zadoff-Chu sequences) that can be adopted in cellular communication without causing sequence identification ambiguity is insufficient. Such insufficiency causes heavy performance degradation for SPI requiring a large number of identification sequences. Moreover, rectangularly-pulsed OFDM preamble/pilot waveforms carrying conventional CA sequences suffer from large power spectral sidelobes and thus exhibit low spectral compactness. This paper is thus motivated to develop several order-I CA sequence families which contain more orthogonal CA sequences while endowing the corresponding OFDM preamble/pilot waveforms with fast-decaying spectral sidelobes. Since more orthogonal sequences are provided, the developed order-I CA sequence families can enhance the performance characteristics in SPI requiring a large number of identification sequences over multipath channels exhibiting short-delay channel profiles, while composing spectrally compact OFDM preamble/pilot waveforms.

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Shih-Hao Lu, Char-Dir Chung, Wei-Chang Chen, Ping-Feng Tsou. 2023-08-22. Orthogonal Constant-Amplitude Sequence Families for System Parameter Identification in Spectrally Compact OFDM. https://arxiv.org/abs/2308.11268

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