著者

小松 和暉 宮路 祐一 上原 秀幸

出版者

IEEE

雑誌

IEEE Transactions on Wireless Communications = IEEE Transactions on Wireless Communications (ISSN:15361276)

巻号頁・発行日

vol.17, no.6, pp.3768-3780, 2018-06

被引用文献数

26

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This paper presents a basis function selection technique of a frequency-domain Hammerstein digital selfinterference canceller for in-band full-duplex communications. The power spectral density (PSD) of the nonlinear selfinterference signal is theoretically analyzed in detail, and a nonlinear self-interference PSD estimation method is developed. The proposed selection technique decides on the basis functions necessary for cancellation and relaxes the computational cost of the frequency-domain Hammerstein canceller based on the estimated PSD of the self-interference of each basis function. Furthermore, the convergence performance of the canceller is improved by the proposed selection technique. Simulation results are then presented, showing that the proposed technique can achieve similar cancellation performance compared with the original frequency-domain Hammerstein canceller and a time-domain nonlinear canceller. Additionally, it is shown that the proposed technique improves the computational cost and the convergence performance of the original frequency-domain Hammerstein canceller.

著者

小松 和暉 宮路 祐一 上原 秀幸

出版者

IEEE

雑誌

IEEE Wireless Communications and Networking Conference (WCNC), San Francisco, CA, 2017 = IEEE Wireless Communications and Networking Conference (WCNC), San Francisco, CA, 2017 (ISSN:15582612)

巻号頁・発行日

pp.1-6, 2017

被引用文献数

12

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In-band full-duplex communications have been spotlighted because they can double the spectral efficiency of the current wireless communication systems. However, it is necessary to mitigate the self-interference (SI). Currently, several time-domain and frequency-domain SI cancellers have been proposed. Timedomain SI cancellers are based on the parallel Hammerstein (PH) model, and they have good flexibility with high computational cost. In contrast, frequency-domain SI cancellers can achieve high cancellation performance with low computational cost but they have less flexibility than time-domain PH based SI cancellers. In this paper, we propose a frequency-domain SI canceller based on the PH model. The proposed scheme estimates the frequency response of the SI channel and regenerates SI signals by the overlap-save method. Therefore, the computational complexity of the proposed scheme is less than time-domain PH based SI canceller. The performance of the proposed scheme is assessed by equivalent baseband signal simulations of a fullduplex transceiver. As a result, the proposed scheme achieves high SI cancellation as the time-domain PH based SI canceller with low computational cost. In addition, the convergence performance of the proposed scheme is faster than the time-domain scheme.

著者

小松 和暉 宮路 祐一 上原 秀幸

出版者

IEEE

雑誌

IEEE Transactions on Wireless Communications = IEEE Transactions on Wireless Communications (ISSN:15361276)

巻号頁・発行日

vol.19, no.7, pp.4424-4438, 2020-07

被引用文献数

41

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This paper presents an iterative estimation and cancellation technique for nonlinear in-band full-duplex transceivers with IQ imbalances and amplifier nonlinearities. The estimation process of the proposed scheme consists of three stages, namely, the channel response estimation, IQ imbalance estimation, and power amplifier and low-noise amplifier (LNA) nonlinearities estimation. For the estimation of the parameters and improvement of the accuracy, distortions are compensated by cancellation or inversion with the latest estimated parameters. On the one hand, the channel response is estimated on the time domain; on the other hand, the IQ imbalance and nonlinearities are estimated on the frequency domain for a more straightforward estimation and superior accuracy. In the cancellation process of the proposed scheme, the received signal is compensated with the estimated parameters of the LNA and receiver IQ imbalance before cancellation because the desired signal is received with a high-power self-interference and is distorted by the radiofrequency receiver impairments. Simulation results show that the proposed technique can achieve higher cancellation performance compared with the Hammerstein canceller when the LNA is saturated by the self-interference. Additionally, the performance of the proposed canceller converges much faster than that of the Hammerstein canceller.