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A J Seeds - One of the best experts on this subject based on the ideXlab platform.

  • a pilot carrier coherent leo to ground downlink system using an optical injection phase lock loop oipll technique
    Journal of Lightwave Technology, 2012
    Co-Authors: Yozo Shoji, M J Fice, Yoshihisa Takayama, A J Seeds
    Abstract:

    A pilot-carrier coherent low-earth-orbit (LEO) satellite to ground (LEO-to-Ground) downlink system using an optical injection phase lock loop (OIPLL) technique is proposed and its feasibility under Doppler Frequency shift conditions is demonstrated. A fiber-optic based experimental system is configured and it is demonstrated that a 10 Gbps BPSK transmission system based on the proposed configuration can successfully maintain stable Frequency and phase locking status under simulated Doppler Frequency shift conditions. It is demonstrated that the stable locking status is maintained over a 10.3 GHz (54 ppm) Frequency offset with a maximum rate-of-change of up to 32.4 GHz/s (168 ppm/s), which is ample to meet the requirement for a coherent LEO-to-Ground downlink system. The locking capability of the experimental system for more rapidly changing Doppler Frequency shift is investigated. It is shown that the OIPLL receiver remains locked for maximum rates of change of 2.6 THz/s (13 500 ppm/s) or more for peak-to-peak Frequency offsets up to 2 GHz (10.7 ppm). The phase noise performance of the system is also investigated and phase noise power of less than -100 dBc/Hz at greater than 1 MHz offset Frequency is achieved even if the received laser signal suffers from a simulated Doppler Frequency shift with peak-to-peak Frequency offset of 2.4 GHz (12.5 ppm) and maximum rate of change of 750 GHz/s (3 900 ppm/s).

  • a pilot carrier coherent leo to ground downlink system using an optical injection phase lock loop oipll technique
    Journal of Lightwave Technology, 2012
    Co-Authors: Yozo Shoji, M J Fice, Yoshihisa Takayama, A J Seeds
    Abstract:

    A pilot-carrier coherent low-earth-orbit (LEO) satellite to ground (LEO-to-Ground) downlink system using an optical injection phase lock loop (OIPLL) technique is proposed and its feasibility under Doppler Frequency shift conditions is demonstrated. A fiber-optic based experimental system is configured and it is demonstrated that a 10 Gbps BPSK transmission system based on the proposed configuration can successfully maintain stable Frequency and phase locking status under simulated Doppler Frequency shift conditions. It is demonstrated that the stable locking status is maintained over a 10.3 GHz (54 ppm) Frequency offset with a maximum rate-of-change of up to 32.4 GHz/s (168 ppm/s), which is ample to meet the requirement for a coherent LEO-to-Ground downlink system. The locking capability of the experimental system for more rapidly changing Doppler Frequency shift is investigated. It is shown that the OIPLL receiver remains locked for maximum rates of change of 2.6 THz/s (13 500 ppm/s) or more for peak-to-peak Frequency offsets up to 2 GHz (10.7 ppm). The phase noise performance of the system is also investigated and phase noise power of less than -100 dBc/Hz at greater than 1 MHz offset Frequency is achieved even if the received laser signal suffers from a simulated Doppler Frequency shift with peak-to-peak Frequency offset of 2.4 GHz (12.5 ppm) and maximum rate of change of 750 GHz/s (3 900 ppm/s).

Yozo Shoji - One of the best experts on this subject based on the ideXlab platform.

  • a pilot carrier coherent leo to ground downlink system using an optical injection phase lock loop oipll technique
    Journal of Lightwave Technology, 2012
    Co-Authors: Yozo Shoji, M J Fice, Yoshihisa Takayama, A J Seeds
    Abstract:

    A pilot-carrier coherent low-earth-orbit (LEO) satellite to ground (LEO-to-Ground) downlink system using an optical injection phase lock loop (OIPLL) technique is proposed and its feasibility under Doppler Frequency shift conditions is demonstrated. A fiber-optic based experimental system is configured and it is demonstrated that a 10 Gbps BPSK transmission system based on the proposed configuration can successfully maintain stable Frequency and phase locking status under simulated Doppler Frequency shift conditions. It is demonstrated that the stable locking status is maintained over a 10.3 GHz (54 ppm) Frequency offset with a maximum rate-of-change of up to 32.4 GHz/s (168 ppm/s), which is ample to meet the requirement for a coherent LEO-to-Ground downlink system. The locking capability of the experimental system for more rapidly changing Doppler Frequency shift is investigated. It is shown that the OIPLL receiver remains locked for maximum rates of change of 2.6 THz/s (13 500 ppm/s) or more for peak-to-peak Frequency offsets up to 2 GHz (10.7 ppm). The phase noise performance of the system is also investigated and phase noise power of less than -100 dBc/Hz at greater than 1 MHz offset Frequency is achieved even if the received laser signal suffers from a simulated Doppler Frequency shift with peak-to-peak Frequency offset of 2.4 GHz (12.5 ppm) and maximum rate of change of 750 GHz/s (3 900 ppm/s).

  • a pilot carrier coherent leo to ground downlink system using an optical injection phase lock loop oipll technique
    Journal of Lightwave Technology, 2012
    Co-Authors: Yozo Shoji, M J Fice, Yoshihisa Takayama, A J Seeds
    Abstract:

    A pilot-carrier coherent low-earth-orbit (LEO) satellite to ground (LEO-to-Ground) downlink system using an optical injection phase lock loop (OIPLL) technique is proposed and its feasibility under Doppler Frequency shift conditions is demonstrated. A fiber-optic based experimental system is configured and it is demonstrated that a 10 Gbps BPSK transmission system based on the proposed configuration can successfully maintain stable Frequency and phase locking status under simulated Doppler Frequency shift conditions. It is demonstrated that the stable locking status is maintained over a 10.3 GHz (54 ppm) Frequency offset with a maximum rate-of-change of up to 32.4 GHz/s (168 ppm/s), which is ample to meet the requirement for a coherent LEO-to-Ground downlink system. The locking capability of the experimental system for more rapidly changing Doppler Frequency shift is investigated. It is shown that the OIPLL receiver remains locked for maximum rates of change of 2.6 THz/s (13 500 ppm/s) or more for peak-to-peak Frequency offsets up to 2 GHz (10.7 ppm). The phase noise performance of the system is also investigated and phase noise power of less than -100 dBc/Hz at greater than 1 MHz offset Frequency is achieved even if the received laser signal suffers from a simulated Doppler Frequency shift with peak-to-peak Frequency offset of 2.4 GHz (12.5 ppm) and maximum rate of change of 750 GHz/s (3 900 ppm/s).

M J Fice - One of the best experts on this subject based on the ideXlab platform.

  • a pilot carrier coherent leo to ground downlink system using an optical injection phase lock loop oipll technique
    Journal of Lightwave Technology, 2012
    Co-Authors: Yozo Shoji, M J Fice, Yoshihisa Takayama, A J Seeds
    Abstract:

    A pilot-carrier coherent low-earth-orbit (LEO) satellite to ground (LEO-to-Ground) downlink system using an optical injection phase lock loop (OIPLL) technique is proposed and its feasibility under Doppler Frequency shift conditions is demonstrated. A fiber-optic based experimental system is configured and it is demonstrated that a 10 Gbps BPSK transmission system based on the proposed configuration can successfully maintain stable Frequency and phase locking status under simulated Doppler Frequency shift conditions. It is demonstrated that the stable locking status is maintained over a 10.3 GHz (54 ppm) Frequency offset with a maximum rate-of-change of up to 32.4 GHz/s (168 ppm/s), which is ample to meet the requirement for a coherent LEO-to-Ground downlink system. The locking capability of the experimental system for more rapidly changing Doppler Frequency shift is investigated. It is shown that the OIPLL receiver remains locked for maximum rates of change of 2.6 THz/s (13 500 ppm/s) or more for peak-to-peak Frequency offsets up to 2 GHz (10.7 ppm). The phase noise performance of the system is also investigated and phase noise power of less than -100 dBc/Hz at greater than 1 MHz offset Frequency is achieved even if the received laser signal suffers from a simulated Doppler Frequency shift with peak-to-peak Frequency offset of 2.4 GHz (12.5 ppm) and maximum rate of change of 750 GHz/s (3 900 ppm/s).

  • a pilot carrier coherent leo to ground downlink system using an optical injection phase lock loop oipll technique
    Journal of Lightwave Technology, 2012
    Co-Authors: Yozo Shoji, M J Fice, Yoshihisa Takayama, A J Seeds
    Abstract:

    A pilot-carrier coherent low-earth-orbit (LEO) satellite to ground (LEO-to-Ground) downlink system using an optical injection phase lock loop (OIPLL) technique is proposed and its feasibility under Doppler Frequency shift conditions is demonstrated. A fiber-optic based experimental system is configured and it is demonstrated that a 10 Gbps BPSK transmission system based on the proposed configuration can successfully maintain stable Frequency and phase locking status under simulated Doppler Frequency shift conditions. It is demonstrated that the stable locking status is maintained over a 10.3 GHz (54 ppm) Frequency offset with a maximum rate-of-change of up to 32.4 GHz/s (168 ppm/s), which is ample to meet the requirement for a coherent LEO-to-Ground downlink system. The locking capability of the experimental system for more rapidly changing Doppler Frequency shift is investigated. It is shown that the OIPLL receiver remains locked for maximum rates of change of 2.6 THz/s (13 500 ppm/s) or more for peak-to-peak Frequency offsets up to 2 GHz (10.7 ppm). The phase noise performance of the system is also investigated and phase noise power of less than -100 dBc/Hz at greater than 1 MHz offset Frequency is achieved even if the received laser signal suffers from a simulated Doppler Frequency shift with peak-to-peak Frequency offset of 2.4 GHz (12.5 ppm) and maximum rate of change of 750 GHz/s (3 900 ppm/s).

Yoshihisa Takayama - One of the best experts on this subject based on the ideXlab platform.

  • a pilot carrier coherent leo to ground downlink system using an optical injection phase lock loop oipll technique
    Journal of Lightwave Technology, 2012
    Co-Authors: Yozo Shoji, M J Fice, Yoshihisa Takayama, A J Seeds
    Abstract:

    A pilot-carrier coherent low-earth-orbit (LEO) satellite to ground (LEO-to-Ground) downlink system using an optical injection phase lock loop (OIPLL) technique is proposed and its feasibility under Doppler Frequency shift conditions is demonstrated. A fiber-optic based experimental system is configured and it is demonstrated that a 10 Gbps BPSK transmission system based on the proposed configuration can successfully maintain stable Frequency and phase locking status under simulated Doppler Frequency shift conditions. It is demonstrated that the stable locking status is maintained over a 10.3 GHz (54 ppm) Frequency offset with a maximum rate-of-change of up to 32.4 GHz/s (168 ppm/s), which is ample to meet the requirement for a coherent LEO-to-Ground downlink system. The locking capability of the experimental system for more rapidly changing Doppler Frequency shift is investigated. It is shown that the OIPLL receiver remains locked for maximum rates of change of 2.6 THz/s (13 500 ppm/s) or more for peak-to-peak Frequency offsets up to 2 GHz (10.7 ppm). The phase noise performance of the system is also investigated and phase noise power of less than -100 dBc/Hz at greater than 1 MHz offset Frequency is achieved even if the received laser signal suffers from a simulated Doppler Frequency shift with peak-to-peak Frequency offset of 2.4 GHz (12.5 ppm) and maximum rate of change of 750 GHz/s (3 900 ppm/s).

  • a pilot carrier coherent leo to ground downlink system using an optical injection phase lock loop oipll technique
    Journal of Lightwave Technology, 2012
    Co-Authors: Yozo Shoji, M J Fice, Yoshihisa Takayama, A J Seeds
    Abstract:

    A pilot-carrier coherent low-earth-orbit (LEO) satellite to ground (LEO-to-Ground) downlink system using an optical injection phase lock loop (OIPLL) technique is proposed and its feasibility under Doppler Frequency shift conditions is demonstrated. A fiber-optic based experimental system is configured and it is demonstrated that a 10 Gbps BPSK transmission system based on the proposed configuration can successfully maintain stable Frequency and phase locking status under simulated Doppler Frequency shift conditions. It is demonstrated that the stable locking status is maintained over a 10.3 GHz (54 ppm) Frequency offset with a maximum rate-of-change of up to 32.4 GHz/s (168 ppm/s), which is ample to meet the requirement for a coherent LEO-to-Ground downlink system. The locking capability of the experimental system for more rapidly changing Doppler Frequency shift is investigated. It is shown that the OIPLL receiver remains locked for maximum rates of change of 2.6 THz/s (13 500 ppm/s) or more for peak-to-peak Frequency offsets up to 2 GHz (10.7 ppm). The phase noise performance of the system is also investigated and phase noise power of less than -100 dBc/Hz at greater than 1 MHz offset Frequency is achieved even if the received laser signal suffers from a simulated Doppler Frequency shift with peak-to-peak Frequency offset of 2.4 GHz (12.5 ppm) and maximum rate of change of 750 GHz/s (3 900 ppm/s).

Xihua Zou - One of the best experts on this subject based on the ideXlab platform.

  • photonic approach for simultaneous measurements of Doppler Frequency shift and angle of arrival of microwave signals
    Optics Express, 2019
    Co-Authors: Lianshan Yan, Xia Feng, Xihua Zou, Wei Pan, Tao Zhou, Bin Luo, Zhiyu Chen
    Abstract:

    A photonic method used to simultaneously measure the Doppler-Frequency-shift (DFS) and angle-of-arrival (AOA) of microwave signals is proposed and experimentally demonstrated. At the remote antenna unit (RAU), the local oscillator (LO) signal and two echo signals are applied to a phase modulator (PM) and a polarization-division-multiplexed Mach-Zehnder modulator (PDM-MZM), respectively. After transmission over a fiber link, the DFS and AOA parameters can be obtained by processing the two low-Frequency electrical signals at the central office (CO). Experimental results show that the DFS between ± 100-kHz with < ± 5 × 10−3-Hz error and the AOA from 1.82° to 90° with <0.85° error at 10 GHz are obtained over a 10-km single mode fiber (SMF) transmission. Moreover, the DFS direction can also be distinguished by comparing the phase difference of two electrical signals.

  • Wideband Microwave Doppler Frequency Shift Measurement and Direction Discrimination Using Photonic I/Q Detection
    Journal of Lightwave Technology, 2016
    Co-Authors: Bing Lu, Lianshan Yan, Xihua Zou, Wei Pan, Yan Pan, Xinkai Liu, Bin Luo
    Abstract:

    An enhanced approach to realizing wideband microwave Doppler Frequency shift (DFS) measurement and direction discrimination based on photonic in-phase and quadrature coherent detection is proposed and demonstrated experimentally. In the proposed approach, the DFS between the transmitted microwave signal and the received echo signal is converted into two quadrature low-Frequency electrical signals through the coherent detection by using an optical hybrid and two balanced photodetectors. The microwave DFS of interest can be estimated with an unambiguous direction, and in particular with a greatly improved resolution. Meanwhile, photonic coherent and balanced detection effectively eliminates the optical signal to signal beating interferences. In the proof-of-concept experiment, the DFSs from -90 to +90 kHz are successfully estimated for microwave signals at 10, 14, 18, and 38 GHz. The measurement errors are estimated to be less than ±5.8 Hz which are an order of magnitude lower than those (i.e., ±60 Hz) released before. Such results provide a high resolution for radial velocity measurement as well. In addition, the performance of the proposed approach in term of the signal-to-noise ratio and stability is discussed.

  • wideband Doppler Frequency shift measurement and direction ambiguity resolution using optical Frequency shift and optical heterodyning
    Optics Letters, 2015
    Co-Authors: Xihua Zou, I Luo
    Abstract:

    A photonic approach for both wideband Doppler Frequency shift (DFS) measurement and direction ambiguity resolution is proposed and experimentally demonstrated. In the proposed approach, a light wave from a laser diode is split into two paths. In one path, the DFS information is converted into an optical sideband close to the optical carrier by using two cascaded electro-optic modulators, while in the other path, the optical carrier is up-shifted by a specific value (e.g., from several MHz to hundreds of MHz) using an optical-Frequency shift module. Then the optical signals from the two paths are combined and detected by a low-speed photodetector (PD), generating a low-Frequency electronic signal. Through a subtraction between the specific optical Frequency shift and the measured Frequency of the low-Frequency signal, the value of DFS is estimated from the derived absolute value, and the direction ambiguity is resolved from the derived sign (i.e., + or -). In the proof-of-concept experiments, DFSs from -90 to 90 kHz are successfully estimated for microwave signals at 10, 15, and 20 GHz, where the estimation errors are lower than ±60  Hz. The estimation errors can be further reduced via the use of a more stable optical Frequency shift module.

  • photonic approach to wide Frequency range high resolution microwave millimeter wave Doppler Frequency shift estimation
    IEEE Transactions on Microwave Theory and Techniques, 2015
    Co-Authors: Xihua Zou, Lianshan Yan, Wei Pan, Liyang Shao
    Abstract:

    High-resolution Doppler Frequency shift (DFS) estimation in a wide Frequency range is essential for radar, microwave/millimeter-wave, and communication systems. In this paper, a photonic approach to DFS estimation is proposed and experimentally demonstrated, providing a high-resolution and Frequency-independent solution. In the proposed approach, the DFS between the transmitted microwave signal and the received echo signal is mapped into a doubled Frequency spacing between two target optical sidebands by using two cascaded electrooptic modulators. Subsequently, the DFS is then estimated through the spectrum analysis of a low-Frequency electrical signal generated from the Frequency beating of the two target sidebands with an improved resolution by a factor of 2. In the experiments, DFSs from ${-}{\hbox{90}}$ to 90 kHz are successfully estimated for microwave/millimeter-wave signals at 10, 15, and 30 GHz, where the estimation errors are lower than $\pm {\hbox{5}} \times {\hbox{10}}^{-10}$ Hz. For radial velocity measurement, these results reveal a range from 0 to 900 m/s and a resolution of ${\hbox{1}} \times {\hbox{10}}^{-11}$ m/s at 15-GHz Frequency band, or a range from 0 to 450 m/s and a resolution of ${\hbox{5}} \times {\hbox{10}}^{-12}$ m/s at 30-GHz band. To eliminate the estimation ambiguity, a reference branch is introduced for generating an indicator Frequency to discriminate the sign of DFS and the direction of radial velocity for approaching or receding motion. In addition, extended discussions on the signal-to-noise ratio, the minimum measurable DFS, and other detection features of the proposed approach are presented.