A high voltage protection device for protecting personnel from injury or th as well as damage to radios and vehicles when a whip antenna comes in contact with overhead high voltage power lines or the like and comprises a high voltage coaxial capacitance device which is coupled in series between the upper and lower section of a whip antenna. The capacitive reactance of the capacitance device is very high at power line frequencies and relatively low at RF frequencies. The capacitance element is comprised of two concentric cylindrical conductors formed in a fiberglass shell and separated from one another by a dielectric such as polytetra fluorethylene.

Whip antenna high voltage protection device

Each conductor of the antenna is fed with a successively delayed phase representation of the input signal to optimize transmission characteristics. Each of the conductors is separated into a number Z of discrete conductor portions by Z-1 capacitive discontinuities. The addition of the capacitive discontinuities results in the formation of an antenna array. The end result of the antenna array is a quadrifilar helical antenna which is nonsquinting (radiates in a given direction independently of frequency).

Nonsquinting end-fed quadrifilar helical antenna

The present invention is a radar platform that detects intruders and wirelessly reports to a key-fob. The entire radar platform is water-resistant and two banks of batteries are included for convenience or extended operation time. The device consists of a MicroPower Radar (MPR), a data acquisition (DAQ) element and a processor. Radar sends a short, low-amplitude signal of radio-frequency (RF) energy toward the target. This signal reflects from the target and is received as a Doppler change in signal amplitude. The radar's RF energy is in the radio frequency band and operates at much lower powers than many mobile devices such as cell phones. This Doppler System change in signal amplitude is filtered, amplified and presented to the DAQ. The DAQ converts the analog Doppler signal into a digital bit-stream and passed to the radar processor. Proprietary software analysis is performed to further filter and to make an alarm determination.

Handheld System for Radar Detection

An isolator assembly for isolating a transmitting and receiving communications antenna member from a mast and connector. The isolator assembly electrically couples an antenna member to a connector for passage of radio frequency energy but also electrically isolates the antenna member from the connector and the mast from a high voltage on the antenna member.

Isolated antenna assembly

The invention is a device for reducing modulation of high frequency signals induced by helicopter rotor blades made of high strength composites and having a metalized leading edge. The device uses a segmented metalized leading edge. The segments are electrically connected by reactive elements selected to alter the self-resonant frequency of the rotor blade and to reduce the antenna Q to a non-interfering frequency range. The reactive elements use "lossy" materials to absorb energy to reduce the magnitude of radio frequency signal induced currents.

Rotor modulation suppressor

A whip antenna is constructed in three sections which screw together end-to-end to form the complete antenna. Each section comprises a flexible fiberglass rod which is surrounded by a sleeve of braided copper wire over a major part of its length, this sleeve serving to pass radio frequency current along the section during use of the antenna. Two of the sections also each provide a capacitor which is connected in the radio frequency path along the antenna. Each of these capacitors is formed by two strips of copper tape which constitute the capacitor electrodes and which lie opposing one another on the surface of the fiberglass rod of the appropriate section.

Geoffrey Thomas Newington

Papers

Flexible antenna with capacative plate coupling