Microwave phased array antennas (PAAs) are very attractive to defense applications and high-speed wireless communications for their abilities of fast beam scanning complex pattern control. However, traditional PAAs based on phase shifters suffer from the beam-squint problem have limited bandwidths. True-time-delay (TTD) beamforming low-loss photonic delay lines can solve this problem. But it is still quite challenging build large-scale TTD beamformers due high hardware complexity. In paper,...

W-band inverse synthetic aperture radar (ISAR) imaging systems are very useful for automatic target recognition and classification due to their high spatial resolution, penetration small antenna size. Broadband linear frequency modulated wave (LFMW) is usually applied this system its de-chirping characteristic. However, nearly all of the LFMW generated in electronic ISAR based on multipliers mixers, suffering seriously from electromagnetic interference (EMI) timing jitter. And...

Solitons are self-reinforcing localized wave packets arising from a balance of linear and nonlinear effects. This definition encompasses the interplay gain loss, leading to concept dissipative solitons that has been instrumental in understanding wide variety mode locking phenomena ultrafast optics. To date, most studies have involved group velocity dispersion as key ingredient for soliton generation. Here, we report on novel kind soliton, both theoretically experimentally, which builds up...

We propose a highly linear radio-over-fiber system with low intermodulation distortion (IMD) using single-drive dual-parallel Mach-Zehnder modulator (SD-DPMZM). The optical carrier is modulated in one of the two parallel modulators, while remaining unmodulated other one. There exists optimal working points for SD-DPMZM that makes its kinds origins third-order IMD (IMD3) have opposite phase and equal intensity, cancel each other; hence output IMD3 suppressed dramatically. Experimental results...

A carrier phase-shifted (CPS) double sideband (DSB) modulation technique in radio-over-fiber (RoF) system is proposed and experimentally demonstrated. By tuning the biases a single-drive dual parallel Mach-Zehnder modulator (SD-DPMZM), optical DSB spectrum acquires additional phase shift. The transmittance response of dispersive RoF link thus being controlled shifted frequency domain. Experiments successfully turned maximum transmission to 10 GHz 15 for both 25 39 km fiber links. This also...

We present a polarization-maintaining PANDA ring-core fiber (PM-PRCF) characterized by the combination of structure with two stress-applying rods. This special design separates adjacent modes and avoids cutoff higher-order modes, which is common problem in elliptical core few-mode fibers. Using high-contrast index ring stress-induced birefringence, PM-PRCF features support for 10 vector effective refractive separations from their >10−4. Broadband performance investigated subsequently over...

This paper reports a photonics-assisted joint radar and communication system for intelligent transportation based on an optoelectronic oscillator (OEO). By manipulating the optical multi-dimensional processing module inserted in OEO loop, two phase-orthogonal integrated signals are generated with low phase noise high frequency, as data loaded overall polarity of pulses. At receiver, single-channel matched filtering two-channel IQ fusion utilized to retrieve range profile, without any...

We present an all-optical stable quadruple frequency dissemination for arbitrary-access-point fiber-optic loop link using photonic microwave phase conjugation. A two-tone optical carrier is transferred as a round-trip probe signal to undergo the propagation delay of entire fiber link. When returns local site, Mach-Zehnder modulator biased at null point used conjugator reverse its phase, thus, implementing At arbitrary remote phase-conjugated photomixed with tapped forward obtain...

Orthogonal frequency division multiplexing (OFDM) signal is a superior dual-functional waveform for the integration of radar sensing and communication in intelligent transportation. But sensitivity to phase noise serious issue introducing interference causing performance degradation during demodulation. In this paper, we explore essential mechanism action generation through theoretical analysis, where OFDM demodulation process power spectrum density (PSD) discussed domain, draw conclusion...

A postcompensation technique for nonlinearity of a Mach-Zehnder modulator in radio-over-fiber (ROF) system is proposed and experimentally demonstrated based on second-order optical sideband processing carrier band attenuation. The phase the shifted to suppress third-order intermodulation distortion (IMD3) direct detection ROF link. attenuated make two kinds origins IMD3 have equal intensity cancel each other out. spurious-free dynamic range 124.8 dB·Hz(2/3) achieved, which about 25 dB more...

A photonics-based wideband distributed coherent aperture radar (DCAR) system is proposed and experimentally demonstrated. In the system, central controlling several spatially dispersed remote transceivers are connected by optical fiber-based time synchronization network. optical-carried orthogonal/coherent linear frequency modulated waveforms (LFMWs) generated a reconfigurable multi-channel arbitrary waveform generator (RMOAWG), signal processing for echo waves also implemented there. While...

Physical layer attacks threaten services transmitted through optical networks. To detect attacks, we present an investigation of spectrum feature analysis (OSFA) and recognition. By analyzing the spectral features signals, recognition detection unauthorized signals can be realized. In this paper, (1) theoretically analyzed factors influencing (OS) simulated these factors. OSs collected from simulation are quantitatively analyzed, extracted by principal component analysis, theoretical...

A tunable dual-frequency optoelectronic oscillator (OEO) based on dual-parallel Mach-Zehnder modulator (DPMZM) with low intermodulation is proposed and experimentally demonstrated. Two electronic band-pass filters are used to select the oscillation modes of two oscillating frequencies achieve OEO (TDF-OEO). Each selected modulated onto one sub-modulator DPMZM. By choosing proper bias conditions DPMZM, components generated by dual-frequencies suppressed. The tuning range TDF-OEO from 1 GHz 15...

In this paper, we proposed a tunable K/W-band OFDM integrated radar and communication system based on Optoelectronic Oscillator (OEO) for intelligent transportation. All-optical signal processing including amplitude asymmetric filtering quadratic phase manipulating is applied in OEO to achieve high-frequency self-excited oscillation, which supports the generation. Its product of maximum detection range capacity cB/4Δf (m·Gbaud), where c light speed Δf subcarrier spacing OFDM. A...

A system for generating radio frequency signals with orbital angular momentum (OAM) is proposed and certificated the first time, which employs an array of multiple optical-true-time-delay elements circular antennas (CAAs). constructive Fourier series theory about CAAs collectively forming OAM beam demonstrated. An optical spectrum processor offers four lines high-resolution time delay by adding a linear phase shifts. The topological charge L=1 produced measured successfully.

In this paper, we present a distributed aperture coherent microwave photonic radar (DCMPR) system by means of high-precision fiber-optic time-frequency synchronization network (OTFSN). The units at different geographic locations are connected with the fiber network. Meanwhile, time and frequency reference central controlling station stably transferred over to each unit, which transmit receive times synchronized signal cohere multiple apertures. Experimentally, demonstrate two-unit DCMPR...

Phased array antennas (PAAs) possessing broadband beamforming capabilities are crucial for advanced radar and wireless communication systems. Nevertheless, traditional phase-shifter-based PAA beamformers frequently encounter the beam-squint issue, which substantially restricts their instantaneous bandwidth. Photonic true-time-delay (TTD) have potential to overcome this challenge, offering ultrawide bandwidth immunity electromagnetic interference. However, practical application is impeded by...

Despite its high range resolution, frequency modulated continuous-wave (FMCW) light detection and ranging (LiDAR) faces challenges from large data volume in long-range detections due to de-chirping receiving principle. We propose a data-compressed FMCW LiDAR with long using time-frequency optical comb (TFOC)-based receiving. By replacing the traditional single linear modulating (LFM) reference signal TFOC, echo at any distance beats nearest LFM tooth. This approach breaks conventional...

In this letter, we propose a novel SDN-based fast lightpath hopping (LPH) mechanism enabled by time synchronization to protect optical networks from eavesdropping and jamming. order realize LPH in networks, establish an routing signalling architecture, set up integer linear programming (ILP) model for fewest-shared-link multipath computation. We also demonstrate the first prototype experiment results show that extremely high hop rate upto 1 MHz can be achieved with acceptable bit error rates...