The Experts below are selected from a list of 294 Experts worldwide ranked by ideXlab platform

Tat Soon Yeo - One of the best experts on this subject based on the ideXlab platform.

  • isar imaging in strong ground clutter using a new stepped frequency Signal Format
    IEEE Transactions on Geoscience and Remote Sensing, 2003
    Co-Authors: Qun Zhang, Tat Soon Yeo
    Abstract:

    In this paper, a new easy-to-implement variant of the stepped-frequency Signal Format is presented for ground clutter cancellation application. A sequence of pulse-groups, where each pulse-group consists of two pulses of the same carrier frequency, is transmitted. The carrier frequency of each subsequent burst is stepped at /spl Delta/f. Simple first-order cancellation of ground clutter can be carried out by comparing the returns of the two adjacent pulses, as the clutter movement (due to wind, etc.) can be assumed negligible within this interval (typically <1 /spl mu/s). A computer simulation is given to illustrate the effectiveness of the proposed method.

  • ISAR imaging in strong ground clutter using a new stepped-frequency Signal Format
    IEEE Transactions on Geoscience and Remote Sensing, 2003
    Co-Authors: Qun Zhang, Tat Soon Yeo
    Abstract:

    In this paper, a new easy-to-implement variant of the stepped-frequency Signal Format is presented for ground clutter cancellation application. A sequence of pulse-groups, where each pulse-group consists of two pulses of the same carrier frequency, is transmitted. The carrier frequency of each subsequent burst is stepped at /spl Delta/f. Simple first-order cancellation of ground clutter can be carried out by comparing the returns of the two adjacent pulses, as the clutter movement (due to wind, etc.) can be assumed negligible within this interval (typically

Qun Zhang - One of the best experts on this subject based on the ideXlab platform.

  • aspects of radar imaging using frequency stepped chirp Signals
    EURASIP Journal on Advances in Signal Processing, 2006
    Co-Authors: Qun Zhang
    Abstract:

    The high-resolution, frequency-stepped chirp Signal can be applied to radar systems employing narrow-bandwidth chirp pulses, in order to enhance the range resolution, and to implement SAR/ISAR imaging capabilities. This paper analyzes the effect of moving targets on the synthetic high-resolution range profile obtained using this Signal waveform. Some constraints are presented for compensation of the radial motion from shift and amplitude depression of the synthetic range profile. By transmitting two chirp pulses with the same carrier frequency in a pulse-set, a method of ground clutter cancellation is designed with respect to this Signal Format. Finally, our simulation data demonstrate the effectiveness of the proposed method.

  • isar imaging in strong ground clutter using a new stepped frequency Signal Format
    IEEE Transactions on Geoscience and Remote Sensing, 2003
    Co-Authors: Qun Zhang, Tat Soon Yeo
    Abstract:

    In this paper, a new easy-to-implement variant of the stepped-frequency Signal Format is presented for ground clutter cancellation application. A sequence of pulse-groups, where each pulse-group consists of two pulses of the same carrier frequency, is transmitted. The carrier frequency of each subsequent burst is stepped at /spl Delta/f. Simple first-order cancellation of ground clutter can be carried out by comparing the returns of the two adjacent pulses, as the clutter movement (due to wind, etc.) can be assumed negligible within this interval (typically <1 /spl mu/s). A computer simulation is given to illustrate the effectiveness of the proposed method.

  • ISAR imaging in strong ground clutter using a new stepped-frequency Signal Format
    IEEE Transactions on Geoscience and Remote Sensing, 2003
    Co-Authors: Qun Zhang, Tat Soon Yeo
    Abstract:

    In this paper, a new easy-to-implement variant of the stepped-frequency Signal Format is presented for ground clutter cancellation application. A sequence of pulse-groups, where each pulse-group consists of two pulses of the same carrier frequency, is transmitted. The carrier frequency of each subsequent burst is stepped at /spl Delta/f. Simple first-order cancellation of ground clutter can be carried out by comparing the returns of the two adjacent pulses, as the clutter movement (due to wind, etc.) can be assumed negligible within this interval (typically

Robert I. Killey - One of the best experts on this subject based on the ideXlab platform.

  • Digital Linearization of Direct-Detection Transceivers for Spectrally Efficient 100 Gb/s/λ WDM Metro Networking
    Journal of Lightwave Technology, 2018
    Co-Authors: Zhe Li, M. Sezer Erkilinc, Eric Sillekens, Polina Bayvel, Tianhua Xu, Benn C. Thomsen, Lidia Galdino, Robert I. Killey
    Abstract:

    Single-polarization, single-photodiode-based direct-detection (DD) transceivers offer advantages for metro networks due to their simple and low-cost optical hardware structure. Single-sideband Nyquist-pulse-shaped subcarrier modulation (SSB Nyquist-SCM) is a promising Signal Format to achieve high inFormation spectral density (ISD) in such DD systems. In this paper, we present theoretical and experimental evaluations of a variety of direct-detection SSB Nyquist-SCM system designs, operating at 100 Gb/s per wavelength in wavelength division multiplexing (WDM) metro network scenarios. Through simulations, several receiver-based digital linearization techniques to overcome the effect of Signal-Signal beat interference were investigated, and their performance compared with alternative approaches, including optical beat-interference cancellation receivers (BICRx) and coherent receivers (both heterodyne and homodyne). Subsequently, experimental assessments of the digitally-linearized DD receivers were carried out. Spectrally efficient (net ISD exceeding 3 b/s/Hz) 4 × 112 Gb/s WDM DD single-sideband 16-QAM Nyquist-SCM transmission over distances of up to 240 km (multi-span links) and 160 km (single-span links without mid-span amplification) were shown to be possible using uncompensated standard single-mode fiber.

  • performance comparison of single sideband direct detection nyquist subcarrier modulation and ofdm
    Journal of Lightwave Technology, 2015
    Co-Authors: Sezer M Erkilinc, Polina Bayvel, Benn C. Thomsen, Stephan Pachnicke, Helmut Griesser, Robert I. Killey
    Abstract:

    Direct detection transceivers offer advantages, including low cost and complexity, in short- and medium-haul links. We carried out studies seeking to identify the Signal Formats which offer the highest inFormation spectral densities and maximum transmission distances for direct detection links. The performance of two spectrally efficient optical Signal Formats, single-sideband (SSB) Nyquist pulse-shaped subcarrier modulation (SCM) and SSB orthogonal frequency-division multiplexing (OFDM), are compared by means of simulations. The comparison is performed for a range of wavelength-division multiplexing (WDM) net inFormation spectral densities up to 2.0 b/s/Hz by varying the Signal bandwidth, modulation cardinality, and WDM channel spacing. The Signal Formats’ tolerance to Signal–Signal beating interference, resulting from square-law detection, is investigated, and the Nyquist-SCM Format is found to suffer lower penalties from this nonlinearity at high inFormation spectral densities. In 7 $\times$ 28 Gb/s WDM transmission at 2.0 b/s/Hz (with electronic predistortion and EDFA-only amplification), Nyquist-SCM Signals can be transmitted over distances of up to 720 km of standard SMF in comparison to a maximum of 320 km with the OFDM Signal Format.

  • fpga based optical transmitters for electronic predistortion and advanced Signal Format generation
    Lasers and Electro-Optics Society Meeting, 2009
    Co-Authors: Robert I. Killey, P M Watts, Y Benlachtar, R Waegemans, Rachid Bouziane, Ramanan Thiruneelakandan, Peter Milder, Deepak Rangaraj, Anthony Cartolano, Robert Koutsoyannis
    Abstract:

    We descld programmable gate arrays, carrying out real-titronic predistortion at 10.7 Gb/s, and 8.35 Gb/s opticald (OFDM) Signal generation.

Ronghui Zhan - One of the best experts on this subject based on the ideXlab platform.

  • isar imaging using a new stepped frequency Signal Format
    IEEE Transactions on Geoscience and Remote Sensing, 2014
    Co-Authors: Jun Zhang, Qinglin Zhai, Ronghui Zhan
    Abstract:

    In stepped-frequency (SF) radar systems, the high-order phase error due to target motion in each burst can blur the range profile seriously. The methods based on motion parameter estimation perform well in most cases. However, the motion parameter estimation is time consuming, which challenges the real-time imaging of a radar target. To solve this problem, a new easy-to-implement variant of SF Signal Format is proposed in this paper. By employing the new Signal, the high-order phase error can be simply eliminated, and the motion parameter estimation is unnecessary, which makes the imaging efficient. The effectiveness of the proposed method is illustrated and analyzed with both simulations and real data.

Tong G Zhou - One of the best experts on this subject based on the ideXlab platform.

  • multi user miso broadcasting for indoor visible light communication
    International Conference on Acoustics Speech and Signal Processing, 2013
    Co-Authors: Zhenhua Yu, Robert J Baxley, Tong G Zhou
    Abstract:

    In this paper, we study multi-user multi-input single-output (MU-MISO) broadcasting for visible light communication (VLC). VLC differs from radio frequency communication in both baseband Signal Format and optical power constraints. We propose a precoding and biasing model for MU-MISO transmitter design in indoor VLC. We formulate and solve optimization problems for maximizing max-min fairness or throughput subject to per transmitting unit optical power constraint. We apply linear zero forcing and zero forcing dirty paper coding techniques and compare them in simulations.