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We propose a method to design and implement the microwave photonic filter with rectangular response by using the frequency comb, spatial light modulator-based spectrum shaper and dispersive element. Numerical results are presented to verify the proposed scheme.
An 117 Gbit/s short range high speed optical interconnection using DMT modulation and adaptive DPD-PTS algorithm is proposed. By comparison with the traditional DPD algorithm, the simulation results show that the DPD-PTS used in the proposed scheme may achieve higher performance without complex equalization algorithm and dispersion compensation, and thus 117 Gbit/s DMT signal can be transmitted over...
Visible light communication (VLC) using light emitted diodes (LEDs) has been considered as the most attractive solution for indoor positioning. In this paper, an indoor visible light positioning system taking account of multiple reflections is investigated. Based on received signal strength indication (RSSI) algorithm, the positioning error distributions are simulated and show that the reflections...
By an orchestra of multiple enabling techniques at the transmitter and receiver, we experimentally demonstrate a single-channel 102.4-Gb/s transmission up to 240-km standard single-mode fiber (SSMF) at C-band with direct detection. At the transmitter, we realize Nyquist-pulse shaping PAM-4 (NPAM-4) modulation and single-sideband modulation by using a dual-drive Mach-Zehnder modulator. At the receiver,...
This paper presents TRx modules based on microwave photonics developed by Tsinghua University and their application in ISAR. The Tx module is based on OAWG, and can produce signal with arbitrary waveforms on the demand with its frequency tuneable from GHz to 100GHz. its bandwidth up to 10GHz, and its maximum duration up to the order of millisecond. The Rx is a coherent frond end with its central frequency...
An equalization algorithm is proposed for carrier-less amplitude and phase (CAP) modulation system, which is regarded as a good candidate for short range optical communications, like electrical power optical fiber communication, optical access network. The constant module algorithm (CMA) combined with support vector machine (SVM) performs the equalization function. The simulation system was setup...
Optical sinusoidal wave generation on four channels simultaneously is experimental demonstrated using a self-starting optoelectronic oscillator. The frequency of the sinusoidal wave can be widely tuned from 25 GHz to 200 GHz with 25-GHz spacing. The timing jitter of the microwave signal extracted from the oscillator is measured to be 218 fs.
A digital free-space optical (FSO) communication over 1km based on double-channel dense wavelength division multiplexing (DWDM) is experimentally demonstrated. We successfully achieve multiplexing and demultiplexing of signals with different rates and different code types.
Strong optical injection into a distributed feedback (DFB) semiconductor is a method to realize a single bandpass microwave photonic filter (MPF). But the out of band suppression ratio (OSSR) is limited by the four wave mixing (FWM) effect, and the 3 dB bandwidth is too large for microwave signals. To improve the OSSR and narrow the 3 dB bandwidth of the MPF, a novel single bandpss MPF based on weak...
We experimentally demonstrate a feedback-assisted 1.08 Gb/s orbital angular momentum (OAM)-based underwater-to-air wireless optical link with a floating mirror for beam steering. The experimental results show favorable performance of the proposed feedback scheme in the present of the change of water level.
In the paper, we propose a new method, namely Random Filtering Mapping (RFM), through which the peak-to-average power ratio (PAPR) of the Generalized frequency division multiplexing (GFDM) signal is reduced. Then, the improved signal is transmitted through the Radio Over Fiber (ROF) system of Single SideBand (SSB) modulation and optical fiber of 60Km. The simulation results show that the PAPR of the...
Novel technologies based on pulse amplitude modulation (PAM) are studied for a high-speed visible light communication (VLC) system. In this paper, we summarize the latest progress on high-speed PAM-VLC systems including phase shifted Manchester coding, Nyquist filter, weighted pre-equalization, multi-band access, and hybrid time-frequency domain equalization, which supporting VLC high data-rate and...
A novel switchable microwave photonic filter (MPF) based on a second-order Lyot loop and an optical phase modulator (PM) is presented and experimentally demonstrated. A broadband light emitted from a broadband optical source (BOS) is sliced by a second-order Lyot loop which acts as a spectrum slicer, then, is modulated by an optical PM and delayed by a dispersive medium. By doing this, a switchable...
We experimentally demonstrate a vector-mode-division-multiplexing (VMDM) system based on opticalfrequency comb (OFC) over 80cm free space optical (FSO) link. The 228 Gbit/s data transmission has been achieved by using two basic vector modes over 20 wavelengths with direct detection orthogonal frequency division multiplexing (DD-OFDM) signal. The result shows that this VMDM system should be a good...
Integrated microwave photonics has attracted a lot of attentions and makes significant improvement in last 10 years. We have proposed and demonstrated several schemes about microwave photonics including waveform generation, signal processing and energy-efficient micro-heaters. Our schemes are all fabricated on silicon-on-insulator chips and have advantages of compactness and capability to integrate...
The finite gain recovery time of the reflective semiconductor optical amplifier (RSOA) causes distortion and pattern dependence at high bit rates in colorless optical network units (ONUs) of WDM passive. optical network (WDN-PON). The all-optical equalizers based on Mach-Zehnder interferometer (MZI) and fiber Bragg grating (FBG) are proposed to improve RSOA bandwidth so that to achieve 10 Gbps upstream...
Frequency and full 360° phase tunable microwave signal generation based on an optoelectronic oscillator is experimentally demonstrated. Frequency tunable 8–24 GHz and full 360° phase shift are obtained. The single-sideband phase noise of the generated microwave signal is measured to be −122 dBc/Hz at 10 kHz offset.
A microwave photonic based RF interference cancellation scheme is proposed to compensate for wideband phase changes of the interference signals, in which microwave photonic phase shifter is particularly employed. In the proposed cancellation scheme, a known interferer is delayed, attenuated, phase shifted so as to be subtracted from the received signal at the output. The microwave photonic phase shifter...
In this paper, we proposed a bandwidth-variable TWDM access network structure which could simultaneously support upstream, downstream and peer-to-peer (PtP) communication directly inter ONUs based on the LCoS-based tunable bandwidth WSS in RN. The WSS improve the network flexibility due to its scalable technology and programmable filtering characteristics. Equivalent experiments are performed to demonstrate...
A high-performance hybrid multiplexer for wavelength division multiplexing (WDM) and polarization-division multiplexing (PDM) is proposed and realized by combining a polarization-splitter-rotator (PSR) and a microring resonator (MRR) array. A 16-channel hybrid multiplexer with eight wavelength-channels and dual polarizations is demonstrated as an example. Any MRR works bi-directionally and provides...
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