Jiangnan Xiao

Fiber-Wireless-Fiber Link for 100-Gb/s PDM-QPSK Signal Transmission at W-Band

We propose and experimentally demonstrate a W-band seamlessly-integrated fiber-wireless-fiber system enabled by photonic millimeter-wave generation and demodulation techniques, in which up to 109.6-Gb/s polarization division multiplexing quadrature phase shift keying signal can be first transmitted over 80-km single-mode fiber-28 (SMF-28), then delivered over a 2-m 2 × 2 multiple-input multiple-output wireless link at 95 GHz and finally transmitted over another 80-km SMF-28 with a bit-error ratio less than the third-generation forward-error-correction limitation of 2 × 102. The proposed fiber-wireless-fiber integration system has throughput comparable with that of fiber-optic communication and is suited to emergency back-up communications.

W-Band 8QAM Vector Signal Generation by MZM-Based Photonic Frequency Octupling

We propose a novel scheme for photonic multiamplitude quadrature-amplitude-modulation (QAM) vector signal generation at microwave/millimeter-wave bands enabled by Mach-Zehnder modulator (MZM)-based adaptive photonic frequency multiplication. In order to attain an electrical millimeter-wave vector signal displaying multiamplitude QAM modulation, such as 8QAM, after square-law photodiode detection, the driving radio-frequency (RF) signal, carrying multiamplitude QAM transmitter data, should be both amplitude- and phase-precoded before used to drive the MZM. We experimentally demonstrate 8QAM vector signal generation at W-band adopting photonic frequency octupling (×8) enabled by our proposed scheme. The MZM is driven by a 12-GHz precoded RF signal carrying 1-GBaud 8QAM transmitter data. The generated 1-GBaud 8QAM vector signal at W-band is air transmitted over 2-m distance. To the best of our knowledge, it is the first time to realize the generation and reception of multiamplitude QAM vector signal by one external modulator at W-band.

QAM Vector Signal Generation by Optical Carrier Suppression and Precoding Techniques

We numerically and experimentally investigate and compare photonic constant- and multi-amplitude quadrature-amplitude-modulation (QAM) vector signal generation at radio frequency (RF) bands enabled by a Mach-Zehnder modulator (MZM)-based optical carrier suppression (OCS) modulation. In order to attain an electrical vector RF signal displaying multi-amplitude QAM modulation, such as 8 QAM and 16 QAM, after square-law photodiode detection, the driving RF signal carrying multiamplitude QAM transmitter data, should be both amplitude- and phase-precoded before used to drive the MZM. However, for constant-amplitude QAM modulation, such as quadrature-phase-shift-keying (QPSK), only phase precoding is needed. We experimentally demonstrate 1-GBd vector signal generation at 12 GHz enabled by an MZM-based OSC modulation, adopting QPSK, 8 QAM, and 16 QAM modulation, respectively. We also experimentally compare the bit error rate performance of the three different vector signals, and the QPSK case is the best, while the 16 QAM case is the worst.

432-Gb/s PDM-16QAM signal wireless delivery at W-band using optical and antenna polarization multiplexing

We have experimentally demonstrated 432-Gb/s PDM-16QAM modulated W-band wireless signal delivery adopting optical and antenna polarization multiplexing with a SE of 11.4b/s/Hz. The BER after 2-m 4×4 MIMO wireless delivery can be less than FEC threshold of 3.8×10-3.

Demonstration of Ultra-Capacity Wireless Signal Delivery at W-Band

High-speed long-haul wireless transmission links are required to meet the demand of mobile backhauling and emergency communications. We experimentally demonstrated ultra-high-speed 432-Gb/s polarization-division-multiplexing 16-ary quadrature amplitude modulation modulated W-band millimeter-wave (mm-wave) signal delivery over a 2-m horn antenna-based (HA-based) 4 × 4 multiple-input multiple-output (MIMO) wireless link, enabled by photonic mm-wave generation and optical/antenna polarization multiplexing. We further achieved the field trial demonstration of 80-Gb/s polarization-division-multiplexing quadrature phase shift keying modulated W-band mm-wave signal delivery over a 300-m Cassegrain antenna-based (CA-based) 4 × 4 MIMO wireless link, adopting photonic mm-wave generation, multi-band multiplexing, and optical/antenna polarization multiplexing. To the best of our knowledge, 80 Gb/s or 74.7 Gb/s after removing 7% forward-error-correction overhead is a record for W-band wireless signal delivery over a few hundred meters.

W-Band PDM-QPSK Vector Signal Generation by MZM-Based Photonic Frequency Octupling and Precoding

We experimentally demonstrate polarization-division-multiplexing quadrature-phase-shift-keying (PDM-QPSK) modulated vector signal generation at the W-band, adopting Mach-Zehnder-modulator-based (MZM-based) photonic frequency octupling and phase precoding techniques. The MZM biased at its maximum transmission point is driven by a 12-GHz precoded vector signal, which is generated by MATLAB programming and carries up to 4-GBd QPSK transmitter data. The phase of the 12-GHz precoded vector signal is one eighth that of the regular QPSK symbol to overcome the phase octupling effect accompanying the frequency octupling during square-law photodiode (PD) detection. Only one polarization beam splitter is needed to implement optical polarization diversity. The generated 96-GHz vector signal can carry up to 4-GBd PDM-QPSK data. To the best of our knowledge, this is the first time that the generation and reception of the polarization multiplexing vector signal has been recognized by one external intensity modulator at the W-band.

High-Frequency Photonic Vector Signal Generation Employing a Single Phase Modulator

In this paper, we propose a novel and simple method to generate millimeter-wave vector signals using only one phase modulator (PM) and phase-precoding technique, in which the precoded microwave vector signal is used for the drive of the single PM. We experimentally demonstrate that this concept of the generation of quadrature-phase-shift-keying-modulated vector signal can be employed in our radio-over-fiber (RoF) system architecture based on our proposed scheme. By this scheme, we simplify the configuration and reduce the cost of the RoF system.

Long-Distance Wireless mm-Wave Signal Delivery at W-Band

W-band (75-110 GHz) is a potential radio frequency band to provide long-distance wireless links for mobile data transmission. We proposed a high-speed long-distance wireless transmission link at W-band based on some enabling technologies and advanced devices, such as antenna polarization multiplexing combined with multiple-input multiple-output, large-gain/high-power W-band electrical amplifiers, high-gain small-beamwidth Cassegrain antennas, and wideband optical/electrical components. We experimentally demonstrated that our proposed wireless transmission link can realize up to 1.7-km wireless delivery of 20-Gb/s@85.5-GHz millimeter-wave signal with a bit-error rate less than 3.8 × 10-3.

OFDM Vector Signal Generation Based on Optical Carrier Suppression

We propose a novel method to generate photonic quadrature-phase-shift-keying (QPSK) orthogonal frequency division multiplexing (OFDM) vector signal using only one Mach-Zehnder modulator, in which the OFDM signal is phase precoded and amplitude precoded according to the square-law characteristic of the photodetector. We theoretically analyze and experimentally demonstrate that this concept of the generation of the QPSK OFDM vector signal can be employed in our system architecture based on our proposed scheme. The results show that the bit-error ratios of the transmission system are less than the forward-error-correction threshold of 3.8 × 10-3. By this scheme, we simplify the configuration and reduce the cost of the OFDM transmission system.

2.0-Gb/s Visible Light Link Based on Adaptive Bit Allocation OFDM of a Single Phosphorescent White LED

In this paper, we present a high-speed visible light communication (VLC) system based on a single commercially available phosphorescent white light-emitting diode (LED). In this system, a preequalization circuit is used to extend the modulation bandwidth, and a differential output receiver is utilized to reduce the system noise. With adaptive bit and power allocation and orthogonal frequency-division multiplexing (OFDM), we experimentally demonstrated a 2.0-Gb/s visible light link over 1.5-m free-space transmission, and the BER is under a preforward error correction limit of 3.8×10-3. To the best of our knowledge, this is the highest white-light VLC data rate using a single phosphorescent white LED.