Abstract: An N-bit analog to digital converter for converting optical signals into digital form is disclosed. The converter comprises N optical signal channels, one channel for each significant bit of the N-bit digital representation of the optical signal. Each optical channel comprises optical waveguides and photodetectors for converting the optical signal into electronic signals. The sensitivity of the photodetectors in each channel varies from most significant to least significant bit in the digital conversion. The electronic signals drive high-speed switching devices, each of which is set to a different threshold depending on which bit of the digital conversion the switch delivers. There are N switching devices directly driven by the N photodetector channels yielding N digital bits representing the magnitude of the optical input signal.

Abstract: A modulated retroreflection system for secure two-way communication and identification includes a transceiver at a first location and a transponder at a second location. The transponder receiving, modulating, and reflecting the signal back to the transceiver includes a retroreflector having a at least one reflective surface coated with an electro-responsive material. The electro-responsive material modulating the reflection coefficient of the reflective surface thereby modulating signals reflected by the surface. The transponder further includes a modulator electrically connected to the electro-responsive material for applying a modulated bias voltage thereby modulating the refractive index and consequently the electrical phase, and/or amplitude of the reflected signal.

Abstract: A variable impedance coaxial transmission line having a center conductor of constant cross-section, an outer conductor surrounding and coaxial with the center conductor and spaced radially therefrom, and a variable dielectric constant material between the center conductor and the outer conductor. The variable dielectric constant material has a plurality of alternating elements of high dielectric material and low dielectric material arranged along the center conductor from a first end to a second end of the center conductor. The invention also includes a reduced size, high-power broadband power/divider incorporating the variable impedance coaxial transmission line.

Abstract: The present invention is directed to an electrical connector for blocking direct current while permitting transmission of alternating currents. The connector includes a first connector member and a second connector member for matingly receiving the first connector member. The first connector member includes a first conductor and the second connector member having a second conductor. The first and second conductors are positioned adjacent to one another and spaced apart by a layer of dielectric material. The dielectric material provides capacitive coupling of alternating currents from one conductor to the other while preventing coupling of direct current from one to the other. It is an object of the present invention to provide an improved electrical connector with an integral dielectric coating for direct current blockage.