Abstract: A laser proximity sensor for a projectile includes a laser diode having front and rear facets. The diode generates a main laser signal and directs a first portion thereof out of the front facet as a source beam. Focusing means focuses the source beam on a target, and focuses the return beam reflected from the target into the laser diode through the front facet. The laser diode receives the return light beam, provides it with a positive gain, mixes it with the main laser signal, and guides it out the rear facet as a mixed beam. A detection focusing device focuses the mixed beam onto a PIN detector. The PIN detector coherently detects the mixed beam and provides an output signal having a perturbation where the target enters the focal field of the focusing optics. A processor detects the output signal from the PIN detector and may activate a fuse on the projectile.

Abstract: A biconical antenna, the halves of which are connected together at the apex by a pair anti-parallel diodes through a pair of parallel conductive whiskers or wires. A pair of quasi-optical lenses focuses energy from a local oscillator and from a submillimeter radio source, respectively, onto the diode pair in the end-fire and broadside direction, respectively. The diode pair spacing is equal to the half wavelength of the local oscillator energy. The local oscillator energy is common mode rejected and causes the incoming radio energy to be sampled by forward biasing the anti-parallel diode pair in synchronism with each zero crossing of the local oscillator energy. Accordingly, the local oscillator energy and noise virtually do not affect the current flow between the halves of the biconical antenna. The current flow represents an intermediate frequency signal corresponding to the difference in frequency between the incoming radio signal frequency and the local oscillator frequency.

Abstract: A backlash filter apparatus for the removal of spurious electrical components of a pre-established amplitude level from a voltage signal. The filter apparatus provide a backlash window to which the input signal comprising a desired signal and its spurious noise component is applied. The spurious noise component is removed in the backlash window, thus providing a jitter-free filter output.