利索-全球专利检索

  1. 登录
  2. 注册

搜索结果

11 条记录 (耗时 0.017 秒)

    Multi Beam Photonic Beamformer
    5.
    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。

    Electro-optic modulator with improved harmonic performance
    10.
    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。