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A broadband photonic RF channelizer with large in-band interference suppression is proposed and experimentally demonstrated based on dual optical frequency combs (OFCs) and photonic image-reject mixers (IRMs). A Ku-band RF signal with a bandwidth of 5 GHz is channelized into five sub-channels with 1-GHz instantaneous bandwidth. The in-band interference, which is a serious problem of conventional photonics-based...
RF front-end based on microwave photonics is presented and demonstrated. A proof-of-concept RF front-end covering S-Ka bands is successfully realized. Image-reject frequency down-conversion and channelized receiving is realized. Reconfigurable photonic frequency up-conversion for RF signals emitting is also demonstrated.
A photonic microwave image-reject and singlesideband mixer is proposed based on a dual-polarization dualdrive Mach-Zehnder modulator. Results show that the image- and sideband-reject ratios of the proposed IRM and SSM are larger than 60 and 30 dB, respectively, and the LO leakage is largely suppressed.
A microwave downconverter based on optical single-sideband modulation by a dualdrive Mach-Zehnder modulator and carrier suppression by a fiber Bragg grating is proposed and demonstrated, which implements multi-octave downconversion with suppressed mixing spurs.
The real-time passenger flow of buses is a very important statistics for intelligent public traffic system. This paper proposes a real-time bus passenger flow statistics scheme based on light-sensitive wireless sensor network. We deploy five light-sensitive wireless sensor nodes at specific locations near the front and the rear doors. By utilizing the fact that the outputs of light-sensitive sensors...
Based on a photonic microwave phase shifter, a microwave image-reject mixer (IRM) with all the mixing spurs suppressed is proposed in this paper, by using a dual-polarization dual-drive Mach-Zehnder modulator (DPol-DMZM). A proof-of-concept experiment is conducted. Due to the wide band and precise 90-degree phase shift introduced by the photonic microwave phase shifter, the image rejection ratio reaches...
In multi-user cooperative diversity systems, energy-efficient optimal power allocation (OPA) is an essential problem. However, most of the existing works only focus on optimizing the overall system energy efficiency (EE), rather than the individual EE for each user. In this paper, we investigate the OPA in multi-user amplify-and-forward cooperative systems aiming at maximizing the EE for each individual...
A Q-band radio-over-fiber (RoF) system for the distribution of uncompressed high-definition (HD) video signal is proposed and demonstrated. To eliminate the fiber dispersion induced RF power fading, which is a serious problem for the Q-band RoF system, a polarization modulator (PolM) based transmitter is applied, by which the peak of the frequency response of the fiber link can be shifted to any desired...
A novel microwave photonic system is proposed to simultaneously perform microwave frequency mixing and phase shifting based on a dual-drive Mach-Zehnder modulator (DDMZM) and an optical filter. In the proposed system, the RF and local oscillator (LO) signals are applied to the two RF ports of the DDMZM, respectively. An optical bandpass filter is followed to suppress one of the LO first-order sidebands...
Microwave photonic mixer has attracted a significant interest in a lot of applications such as radio over fiber system, satellite payload and radar system, thanks to the advantages in terms of low loss, high isolation and immunity to electromagnetic interference as compared with the conventional electronic mixer. However, the mixing spurs, which is an inevitable problem for any frequency mixer, is...
Outage probability is one of the most important performance measures for cooperative communication systems. And the closed-form solution on exact outage probability is essential for many further studies, such as optimal power allocation and rate control. However, as far as we know, the issue remains open for multiuser linear network coded cooperation (LNCC), which is a technology integrating linear...
Network Coding has attracted significant attention in recent years, and it has been widely applied in broadcast, multicast and unicast. Nevertheless, the study on network coding in convergecast is still in the theoretical analysis and the simulation stage. In order to investigate the network coding gain of convergecast in realistic wireless sensor networks, a network coding-based convergecast scheme...
A reconfigurable photonic microwave mixer for frequency downconversion based on an optical hybrid is proposed and demonstrated. By simply changing the photodetection method, such as the direct detection, balanced detection, or double detection, a single-ended photonic microwave mixer, balanced mixer, I/Q mixer or image-reject mixer (IRM) can be realized. In a proof-of-concept experiment, an 18-GHz...
A high-resolution optical vector network analyzer (OVNA) based on a novel optical single sideband (OSSB) modulation is proposed and experimentally demonstrated. The key module in the proposed OVNA is the novel OSSB modulator with all even- and negative-order sidebands suppressed. When the OSSB modulator is applied into the OVNA, both the bandpass and bandstop responses can be measured. The measurement...
A novel photonic frequency downconverter is proposed and demonstrated using a single dual-drive Mach-Zehnder modulator (DMZM). In the proposed scheme, the local oscillator (LO) and radio frequency (RF) signals are sent to the two RF ports of the DMZM, respectively. By biasing the modulator at the minimum transmission point, a downconverted intermediate frequency (IF) signal with the RF and LO components...
Convergecast is probably the most common communication style in wireless sensor networks (WSNs). And network coding (NC) is a promising concept to improve throughput or reliability of convergecast. Most of the existing works have mainly focused on exploiting these benefits without considering its potential adverse effect. In this paper, we argue that network coding may not always benefit convergecast...
A radio over fiber system for transmission of 3-Gb/s uncompressed HD video is proposed and demonstrated. By using a polarization modulator (PolM) in the transmitter, the power fading caused by the dispersion of the optical fiber is effectively reduced. In the receiver, an injection-locked frequency-doubling optoelectronic oscillator (OEO) is employed to simultaneously extract the RF carrier and perform...
A radio over fiber system for transmission of 3-Gb/s uncompressed HD video is proposed and demonstrated. By using a polarization modulator (PoIM) in the transmitter, the power fading caused by the dispersion of the optical fiber is effectively reduced. In the receiver, an injection-locked frequency-doubling optoelectronic oscillator (OEO) is employed to simultaneously extract the RF carrier and perform...
A radio over fiber system for transmission of 3-Gb/s uncompressed HD video is proposed and demonstrated. By using a polarization modulator (PoIM) in the transmitter, the power fading caused by the dispersion of the optical fiber is effectively reduced. In the receiver, an injection-locked frequency-doubling optoelectronic oscillator (OEO) is employed to simultaneously extract the RF carrier and perform...
A radio over fiber system for transmission of 3-Gb/s uncompressed HD video is proposed and demonstrated. By using a polarization modulator (PolM) in the transmitter, the power fading caused by the dispersion of the optical fiber is effectively reduced. In the receiver, an injection-locked frequency-doubling optoelectronic oscillator (OEO) is employed to simultaneously extract the RF carrier and perform...
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