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    Electro-optic modulator with improved harmonic performance
    5.
    发明授权
    Electro-optic modulator with improved harmonic performance 失效
    具有改善谐波性能的电光调制器

    公开(公告)号：US06204951B1

    公开(公告)日：2001-03-20

    申请号：US09082620

    申请日：1998-05-19

    申请人： James F. Coward ,  Ting K. Yee ,  Peter Chang ,  Abraham Kou

    发明人： James F. Coward ,  Ting K. Yee ,  Peter Chang ,  Abraham Kou

    IPC分类号： G02F103

    CPC分类号： G02F1/225 ,  G02F1/2255 ,  G02F2203/19

    摘要： An electro-optic modulator includes a splitting section, at least three transmission legs, an RF phase-shifting section, a DC-phase shifting section, and a combining section. The splitting section splits a received optical signal into sub-signals, one for each transmission leg. The RF phase-shifting section phase shifts at least two of the sub-signals by an amount proportional to a received RF signal; while the DC phase-shifting section phase shifts at least two of the sub-signals by a DC phase. The combining section combines the phase-shifted sub-signals into a modulated optical signal. In a preferred embodiment, the modulator is characterized by design parameters, such as splitting ratio, DC phase shift, RF coupling efficiency, and combining ratio, and these design parameters are selected to ensure that the modulator meets predetermined performance characteristics, such as maximum harmonic levels or minimum signal to noise ratios.

    摘要翻译： 电光调制器包括分离部分，至少三个传输腿，RF相移部分，DC相移部分和组合部分。 分离部分将接收到的光信号分成子信号，每个传输分支一个。 RF相移部分将至少两个子信号相移一个与所接收的RF信号成比例的量; 而直流相移部分通过DC相位将至少两个子信号相移。 组合部分将相移的子信号组合成调制的光信号。 在优选实施例中，调制器的特征在于设计参数，例如分频比，DC相移，RF耦合效率和组合比，并且选择这些设计参数以确保调制器满足预定的性能特性，例如最大谐波 电平或最小信噪比。

    Photonic mixer for photonically multiplying two electrical signals in two optically interconnected interferometric modulators operated at modulation outside the linear range
    6.
    发明授权
    Photonic mixer for photonically multiplying two electrical signals in two optically interconnected interferometric modulators operated at modulation outside the linear range 失效
    光子混合器，用于在两个光学互连的干涉式调制器之间进行光子倍增，在线性范围外的调制下工作

    公开(公告)号：US5323406A

    公开(公告)日：1994-06-21

    申请号：US970752

    申请日：1992-11-02

    申请人： Ting K. Yee ,  James F. Coward ,  Peter H. Chang

    发明人： Ting K. Yee ,  James F. Coward ,  Peter H. Chang

    IPC分类号： G02F1/225 ,  G02F2/00 ,  H01S5/0687 ,  H01S3/13

    CPC分类号： G02F1/225 ,  G02F2/002 ,  G02F2203/19 ,  H01S5/0687

    摘要： A Mach-Zehnder modulator (MZM), which divides a CW laser beam into two optical portions, is biased at a 180.degree. phase difference between the two optical portions. An RF signal and an LO signal are simultaneously applied to one of the optical portions of the laser beam to produce phase changes between the two optical portions. The two optical portions of the laser beam are then recombined into an optical output beam, which is detected by a photodetector. The photodetector generates a photocurrent, which contains a component at a beat frequency--i.e., the frequency difference between the RF and LO frequencies. The waveform of the photocurrent component at the beat frequency is substantially the same (except for amplitude and a fixed phase shift) as the waveform of the RF signal.

    摘要翻译： 将CW激光束分成两个光学部分的马赫 - 曾德调制器（MZM）被偏置在两个光学部分之间的180°相位差处。 RF信号和LO信号同时施加到激光束的光学部分之一，以产生两个光学部分之间的相位变化。 然后将激光束的两个光学部分重新组合成由光电检测器检测的光输出光束。 光电检测器产生光电流，其包含以频率为单位的分量，即RF和LO频率之间的频率差。 拍频时的光电流成分的波形与RF信号的波形基本相同（振幅除以固定的相移）。

    Multi Beam Photonic Beamformer
    10.
    发明申请
    Multi Beam Photonic Beamformer 审中-公开
    多光束光子束成形器

    公开(公告)号：US20090027268A1

    公开(公告)日：2009-01-29

    申请号：US11464740

    申请日：2006-08-15

    申请人： James F. Coward

    发明人： James F. Coward

    IPC分类号： H01Q3/22

    CPC分类号： H01Q3/2676 ,  H01Q3/22

    摘要： A true time delay beamformer for RF/microwave phased array antenna systems using multiple laser sources, optical modulators to convert the electrical signal to a modulated optical signal, standard optical fiber for creating time delays, dispersive optical fiber for creating delays, optical splitting and/or switching section, photodetectors to convert the modulated optical signal to an electrical signal, and a signal combining section. The true time delay beamformer has the capability to create multiple simultaneous RF/microwave antenna beams. One (more lasers) is used to source one (or more) wavelengths of light to the optical modulator. The signal from one (or more) antenna elements drive the optical modulator. The light from the optical modulator passes through the standard optical fibers and/or the dispersive optical fibers to create time delay variation for one optical modulator relative to another allowing for the formation of RF/microwave beams. Fixed location RF/microwave beams can be generated by a static network of standard and/or dispersive optical delay fibers. Steering of the location of the RF/microwave beams can be accomplished by an optical switching mechanism which could be based on MEMs and/or wavelength routing based switching. Finally, all the signals for a RF/microwave beam are summed to form a single output. The summing can occur either optically before the photodetectors and/or electrically after the photodetectors.

    摘要翻译： 用于使用多个激光源的射频/微波相控阵天线系统的真实时间延迟波束形成器，用于将电信号转换成调制光信号的光调制器，用于产生时间延迟的标准光纤，用于产生延迟的分散光纤，光分裂和/ 或切换部分，光电检测器将调制的光信号转换为电信号，以及信号组合部分。 真正的时间延迟波束形成器具有创建多个同时的RF /微波天线波束的能力。 一个（更多的激光器）用于将一个（或多个）波长的光源发送到光学调制器。 来自一个（或多个）天线元件的信号驱动光学调制器。 来自光学调制器的光通过标准光纤和/或色散光纤，以产生相对于允许形成RF /微波波束的另一光调制器的时间延迟变化。 固定位置RF /微波波束可以由标准和/或色散光延迟光纤的静态网络产生。 可以通过可以基于基于MEM和/或基于波长路由的切换的光学切换机制来实现RF /微波波束的位置的转向。 最后，将RF /微波波束的所有信号求和，形成单个输出。 求和可以在光电检测器之前光学地发生和/或在光电检测器之后进行。