In this paper, the probabilistically shaped polar-coded multiple-input multiple-output free-space optical (MIMO-FSO) communication system with or without spatially correlated (SC) fading is investigated to improve transmission performance. The designed shaping-polar encoder can flexibly generate three typical shapes of distribution via shaping bits and be decoded in the conventional method. The achievable information rate (AIR) of MIMO-FSO systems with or without SC fading is evaluated to determine the number of shaping bits for the shaping-polar encoder.
View Article and Find Full Text PDFIntact and healthy hair follicles are important for hair growth after hair follicle transplantation. However, effective and practical evaluation methods for the quality of hair follicles are currently lacking. In the present study, we developed a novel fast staining method for histological examination of hair follicles.
View Article and Find Full Text PDFIn this Letter, we first propose and demonstrate a real-time in-band full duplex (IBFD) transmission system based on adaptive optical self-interference cancellation (OSIC). The field programmable gate array (FPGA) is used for high-speed and real-time orthogonal frequency-division multiplexing (OFDM) transmission. The hybrid criteria regular triangle (RT) algorithm is first proposed to combine signal power and the bit error rate (BER) together as the objective function to realize the adaptive control process.
View Article and Find Full Text PDFA wideband multipath self-interference cancellation (SIC) system employing both dual-drive Mach-Zehnder modulator-based analog SIC and least mean square (LMS) algorithm-based pre-adaptive filter digital SIC is proposed and demonstrated for the cancellation of multipath self-interference (SI) and facilitation of in-band full-duplex (IBFD) orthogonal frequency-division multiplexing (OFDM) signal transmission. The multipath effect is an unavoidable challenge in SIC due to the dynamic and unpredictable properties in each path, as well as the need for separate matching components for compensating for each path. In this Letter, an LMS algorithm-based adaptive filter is used as a pre-equalizer to adapt and generate the matching signal to the closest approximate of the multipath SI signal.
View Article and Find Full Text PDFAn optically-enabled radio frquency (RF) self-interference cancellation system is demonstrated for over-the-air in-band full duplex transmission, based on a signal-of-interest (SOI) driven regular triangle algorithm. Since the goal of a self-interference cancellation system is to retrieve the SOI that is masked by the in-band interference signal, using the SOI quality as the driven parameter for optimizing the self-interference cancellation performance is a natural and effective way to allow the system to adapt to changes and obtain the best cancellation performance. Since regular triangle algorithm has short iteration time, bursts of pseudo-random binary sequence would be used between real data transmission for optimizing the self-interference cancellation performance.
View Article and Find Full Text PDFIn this paper, we propose an adaptive optical self-interference cancellation using regular triangle algorithm for in-band full-duplex systems. By using this algorithm, the manual adjustment of the tunable optical time delay line and attenuator is replaced with the adaptive program to change the delay and attenuation for achieving optimal cancellation point. The adjustment process is simplified as a convex function problem.
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