Measurement of linear frequency modulation (LFM) signal is significant for radar, communication, and electronic reconnaissance fields. An LFM a wideband whose varies linearly with time, traditional measurement methods require very high sampling rates heavy processing to estimate parameters the signal. In this article, we propose multichannel cooperative (MCS) system based on finite rate innovation (FRI) theory sample real-valued pulse sequence (LFMPS). The MCS consists three parts:...

The joint estimation of the spectrum, carrier, and direction arrival (DOA) is significant in radar, sonar, wireless communications, cognitive radio systems. traditional parameter measurement methods based on Shannon–Nyquist theorem require very high sampling rates, which put a lot pressure sampling, processing, storage devices. In this article, novel beamforming modulated wideband converter (BMWC) system for DOA proposed to improve robustness reduce structural complexity. From spatial signal...

Ceramic fiber aerogels are attractive thermal insulating materials. In a thermomechanical coupling environment, however, they often show limited mechanical strength and considerably increased heat transfer which can lead to runaway. this paper, inspired by bird's nest nacre, we demonstrate sample strategy combining sedimentation layer-by-layer assembly fabricate ultrastrong mullite (MFAs) with quasi-ordered structures. The fibrous layers bridges constructed in self-assembly process....

The modulated wideband converter (MWC) is a sub-Nyquist sampling system recently proposed for sparse multi-band signals. However, due to non-ideal analogue components, transfer-matrix calibration required the successful reconstruction. In practice, it difficult control phases of consecutive sinusoidal inputs precisely which are used calibrate transfer-matrix. Here, authors propose method MWC with digital expanded channels when unknown. As oblique elements equal, can estimate unknown first....

Spectrum measurement and direction of arrival (DOA) estimation methods based on traditional Nyquist theory lead to high sampling rate a large amount data, which bring challenges hardware signal processing. An array cooperative modulated wideband converter (ACMWC) sub-Nyquist system for spectrum DOA is proposed in this work. Based linear (LA) MWC structure with an arbitrary element position, we construct unified space-frequency domain sparse model by combining the modulation information...

Abstract 1D flexible fibers assembled 3D porous networked ceramic fiber aerogels (CFAs) are developed to overcome the brittleness of traditional particle aerogels. However, existing CFAs with disordered and quasi‐ordered structures fail balance relationship between flexibility, robustness, thermal insulation. Creating novel architectural an excellent combination performances has proven extremely challenging. In this paper, a strategy is adopted fabricate mullite fibrous (MFAs) ordered by...

With the development of radar, wireless communications, remote sensing and other fields, signal bandwidth is getting wider. Traditional spectrum direction arrival (DOA) estimation based on Nyquist sampling leads to high rate, which poses challenges acquisition processing equipment. In this paper, a novel sub-Nyquist DOA method space-time trilinear model proposed improve performance, also solve rank deficiency problem in presence coherent signals. First, uniform liner array (ULA) modulated...

We consider the problem of estimating carrier and two-dimensional direction arrival (2D-DOA) sparse multiband signals composed several narrowband transmissions. The traditional sampling methods based on Shannon-Nyquist theorem bring great pressure to storage devices. In this paper, joint estimation 2D-DOA signal sampled by two L-shape arrays modulated wideband convertor (MWC) is proposed. reconstruction algorithm ESPRIT method overcomes pairing issue between three parameters. Simulation...

The joint carrier frequency and two-dimensional direction of arrival (2D-DOA) estimation is a significant problem for radar communication systems. With the development information technology, spectrum signal wider wider, but effective occupied bandwidth narrower. traditional sampling methods based on Shannon-Nyquist theorem bring great pressure to storage devices. In this paper, new frequencies 2D-DOAs method proposed. transmissions received sampled by L-shape delay arrays architecture...

Linear frequency modulation (LFM) signals exist widely in many engineering applications, such as radar, sonar, wireless communications, and electronic reconnaissance, where stretch processing is commonly adopted to reduce the bandwidth. In this paper, a method of sub-Nyquist sampling parameter estimation LFM proposed based on FRI theory. The first mixes received signal with its delayed version. Then, mixed filtered by kernel sampled at low rate. Finally, parameters are estimated from rate...

Range-Doppler detection with pulse sequences exists widely in Radar, sonar, ultrasound imaging, and many other engineering applications. However, the classic methods require a high sampling rate for wideband pulses, Doppler estimation slow time sub-Nyquist may suffer from phase wrapping. In this brief, sequential-based range-Doppler method fast is proposed. Utilizing finite of innovation (FRI) theory, range parameters can be estimated several Fourier coefficients. The determined by number...

Finite rate of innovation (FRI) sampling is widely used in modern high-resolution range-Doppler (RD) detection systems to reduce the rate. However, as decreases, method becomes more noise-sensitive. This study proposes a deep atomic norm denoising network (DAND-Net) denoise FRI samples RD signals and estimate noise levels (NLs). Based on sparse common support property samples, problem was modeled an soft thresholding problem, which jointly multiple measurement vectors could be unfolded into...

In recent years, our country is facing the increasingly serious problem of low fertility, has been in trap and population development imminent. How to effectively improve current situation fertility rate alleviate impact an important topic that we need study urgently. As central city China, Shanghai's fast-paced living environment rapidly developing social status high prices consumption have indirectly or directly led extremely obvious aging trend Shanghai, which a typical representative...

Pulse streams are a kind of finite rate innovation (FRI) signal that widely exist in many engineering applications. According to the FRI theory, nonconsecutive sampled Fourier coefficients (FCs) have better parameter estimation effects than consecutive ones. In this brief, we propose general sampling system for pulse based on multichannel random modulation (MRM). Jointly using samples, multiple sets FCs distinct frequency bands can be analytically calculated by solving least-squares...

Compressive sampling has always been an effective way of signal processing, and the most ideal one is modulated wideband converter(MWC). Unfortunately, in practical applications, multi-channel structure MWC will face non-ideal factors brought by system environment. The conventional method generally to pre-calibrate first, so blind gain phase calibration(BGPC) that can recover calibrate at same time becomes a novel attractive technology. In this article, calibration model for established,...

As the signal spectrum in modern information technology becomes wider and wider, multi-band signals are distributed a frequency range of tens GHz. It covers very wide but each RF has narrow band, distribution location band (or carrier frequency) is completely unknown. For receiver, single-band transmitted together constitute signal. The sampling rate required to jointly estimate space domain parameters these getting higher higher. Modulated wideband converter system an analog conversion for...