Optical Time Division Multiplexing Techniques Research Articles

Towards High-Resolution Imaging With Photonics-Based Time Division Multiplexing MIMO Radar

A photonics-based time division multiplexing (TDM) multiple-input and multiple-output (MIMO) radar is proposed to realize high-resolution imaging. In this MIMO radar, multiple transmitters generate time-domain orthogonal linearly frequency modulated (LFM) signals based on microwave photonic frequency octupling and optical TDM technique, and multiple receivers implement dechirping of the multi-channel radar echoes based on microwave photonic frequency mixing. The microwave photonic techniques make the system capable to generate and process broadband radar signals, and the TDM yields a high spectral efficiency, which allows a large bandwidth in each transmitter and receiver. Meanwhile, the TDM-MIMO ensures complete orthogonality between different channels and enables good flexibility in arranging more transmit and receive channels. Therefore, the proposed photonics-based TDM-MIMO radar can achieve both high range resolution and high angular resolution. In the experiment, a photonics-based 4 × 8 TDM-MIMO radar is established which has an operation bandwidth of 8 GHz in each transmit channel. The range resolution and angular resolution are estimated to be 1.9 cm and 1.1°, respectively. A broadband back projection (BP) imaging algorithm with both frequency and time-delay dependent phase compensation is proposed, based on which high resolution imaging of single and complex targets is achieved.

Experimental demonstration of RoF-DAS over WDM-PON with bandpass-sampling and optical TDM techniques

This paper reports the demonstration of a radio over fiber (RoF) - distributed antenna system (DAS) over a wavelength division multiplexing - passive optical network (WDM-PON) with multiple input multiple output (MIMO) by employing bandpass-sampling and optical time division multiplexing (TDM) techniques to realize next generation broadband wireless access with a gigabit-class throughput. We experimentally evaluate the performance of two optical transmissions of radio frequency (RF) signals, which are multiplexed 2.4 and 5GHz bands 802.11n RF signals in the time-domain and distributed 2.4GHz band 2×2 MIMO 802.11n RF signals with 2 channels WDM.

Optical sampled subcarrier multiplexing scheme for nonlinear distortion reduction in lightwave CATV networks

A nonlinear distortion reduction scheme is proposed and demonstrated for subcarrier multiplexed optical CATV networks based on optical sampling and optical time division multiplexing techniques. Intermodulation distortion is reduced by about 10 dB for a 40-channel system.