Interrupted sampling repeater jamming (ISRJ) is a classic active coherent jamming. Due to its structural limitations, it has inherent defects such as a discontinuous time–frequency (TF) distribution, strong distribution regularity of pulse compression results, limited jamming amplitude, and strong false targets lagging behind the real target. These defects have not been fully resolved yet due to the limitation of the theoretical analysis system. Based on the analysis of the influence factors of ISRJ on the interference performance for linear-frequency-modulated (LFM) and phase-coded signals, this paper proposes an improved ISRJ method based on the joint subsection frequency shift and two-phase modulation. The coherent superposition of jamming signals at different positions for LFM signals is achieved by controlling the frequency shift matrix and the phase modulation parameters to form a strong pre-lead false target or multiple positions and ranges of blanket jamming areas. For the phase-coded signal, the pre-lead false targets are generated through code prediction and the two-phase modulation of the code sequence, resulting in similar noise interference. The simulation results show that this method can overcome the inherent defects of ISRJ.

In this letter, an innovative two-stage hierarchical scheme specifically intended for dual-circularly-polarized (DCP) antenna decoupling is first presented and investigated. Based on this method, a DCP antenna for simultaneous transmit and receive (STAR) sensing systems is designed and demonstrated. Through sequential decoupling procedures of feeding rearrangement for coupling decomposition in the first stage and weak-field-based self-decoupling in the second stage, the mutual coupling of Tx and Rx antennas is reduced. A prototype is fabricated and measured, showing measured | S_ii | < -10 dB ( i = 1, 2, 3, 4) and axial ratio less than 1.5 dB covering an operating bandwidth from 4.35 to 5 GHz (13.9%). Besides, the measured Tx-Rx isolation is higher than 20 dB in 4.35-4.75 GHz with a maximum of 44 dB. Compared with existing counterparts, the proposed antenna demonstrates enhanced isolation across a considerable bandwidth, high total efficiency, and consistent Tx/Rx radiation patterns, positioning it as a promising candidate for STAR sensing applications.

Self-interference (SI) is regarded as a main challenge in in-band full-duplex (IBFD) radios. In this letter, an augmented structure for neural networks (NNs)-based cancelers is proposed to suppress the nonlinear SI. By enhancing the higher-order nonlinear representations and incorporating the connection information of grid structure into the augmented structure, the proposed NNs-based cancelers significantly improve SI cancellation performance. Compared to existing NNs, the proposed NNs-based cancelers require less complexity when realizing comparable cancellation performance to the polynomial-based canceler, and improve the SI cancellation ratio by about 1 dB. Moreover, the residual SI signal power can be reduced to only 1.73 dB above the noise floor with minimal increase in complexity.

The existence of multiple self-interference (SI) signal components, particularly the nonlinear ones, seriously constrains the performance of self-interference cancellation (SIC) methods. To decrease the complexity of SIC methods in full-duplex devices, this article proposes a power analysis method for SI signal components in a full-duplex transceiver. The proposed method comprises a separate analysis algorithm and a system-level power model. Initially, the algorithm is conducted to obtain the spectrum of the linear and nonlinear components in the power amplifier (PA) output signal. Once the linear-to-nonlinear power ratio (LNPR) has been obtained, a system-level power model is constructed by taking both the transmitter noise and analog-to-digital converter (ADC) quantization noise into account. The proposed power model allows for the allocation of SIC method performance in multiple domains during the design of full-duplex transceivers at the top level, thereby reducing the overall system complexity. The simulation results demonstrate that in a full-duplex transceiver with only antenna isolation, the power of the SI signal component is susceptible to alterations due to the operating waveform and transmission power. Finally, the accuracy of the power analysis method is verified through measurement and Simulink.

Simultaneous transmission and reception (STAR) jammers offer superior real‐time performance over transceiver time‐sharing jammers, while the self‐interference (SI) represents a significant challenge for their implementation. To address this issue when SI is correlated with received signal, this paper proposes a digital self‐interference cancelation (SIC) method based on multi‐domain jamming (MDJ) frequency‐shift fingerprint design from the signal characteristic level. This method utilises the frequency‐shift fingerprint and the frequency offset introduced by the jammer's inherent forwarding delay to distinct SI and radar signals. Parameters influencing the frequency‐domain characteristics of the signal, such as frequency‐shift, propagation delay and signal bandwidth, are related to the configuration of the band‐pass filter (BPF), thereby affecting the isolation performance of the proposed method. Since the fingerprint also impacts the jamming effect, it must be carefully designed to ensure the effectiveness of the radar jamming and SIC scheme. Simulation results demonstrate that the proposed method achieves superior cancellation performance compared to traditional adaptive filtering algorithms, effectively jams the radar and exhibits better performance in broadband scenarios.

In order to verify the accuracy of the results of the virtual simulation experiment system on the gravity dam stress experiment line in the experimental teaching process, this study specially carried out the online experiment of gravity dam stress experiment and got the results, and further carried out the online manual experiment in the laboratory. The results of the two experiments were almost the same, which verified the feasibility of the virtual simulation experiment system on the gravity dam stress experiment line and led to the advantages of the three-dimensional virtual simulation experiment. Changing the teaching mode to online preview and offline experience of authenticity experiment aims to make up for the shortcomings in teaching and achieve good teaching results.