Matches 351 - 400 out of 406 < 1 2 3 4 5 6 7 8 9 >
Match Document Document Title
4297701 Rangefinder using expanded time delay  
The system is comprised of a plurality of hand held units carried by golfers, a plurality of flagstick units located at a golf course and a master Clubhouse unit. Each hand held unit includes a...
4278976 Remote sensing device  
A system for battlefield and enemy support area surveillance. An air-drop unit monitors and records on tape enemy activity, and plays back and transmits the monitored data at high speed when...
4278977 Range determining system  
A range finding method and system comprising an interrogator and a transponder. The interrogator generates a signal with a first portion comprising a carrier signal amplitude modulated by a first...
4260983 Presence sensing detector and system for detecting a receiver/transmitter device affixed to an article  
A presence sensing system comprises a detector having a transmitter for transmitting an interrogation signal to an area to be kept under surveillance and a receiver for receiving a presence...
4249176 Following distance measuring communication system  
A following distance measuring communication system comprising a transmitter and a receiver which are mounted on the front part of a following automotive vehicle, a time measuring unit connected to...
4173016 Interpersonal-introduction signalling system  
An interpersonal-introduction signalling system includes a receiving and transmitting transceiver having a relatively short range response and of such size as to permit convenient carrying by a...
4170773 Precision approach sensor system for aircraft  
A microwave interrogation-transponder system for controlling the airborne rendezvous and closure of two aircraft for aerial refueling and the like. The system of the invention includes a microwave...
4139844 Surveillance method and system with electromagnetic carrier and plural range limiting signals  
A microwave carrier signal is transmitted throughout a surveillance field. Two low frequency signals are also radiated into the field from opposite sides to limit the field size. A miniature...
4107675 Transponder-responder system  
A transponder-responder system is provided which comprises a home station and at least one remote station. A transmitter at the home station periodically generates interrogation pulses by means of...
4099180 Geographic gain time control  
Apparatus is provided for modifying a conventional target locating system in which targets respond to an interrogation signal by transmitting a reply, and the target location is deduced from the...
4072946 Method and apparatus for measuring the distance between two stations  
A method and system for determining the distance between two stations interconnected through a carrier wave connection for data transmission by frequency modulation (FM) or phase modulation (PM)...
4042970 Dual frequency narrow-band frequency modulated keyable control circuit and keying circuit therefor  
A keyable control circuit generates a narrow-band FM signal. A keying circuit, containing two tuned circuits, placed next to the tank coil of the keyable control circuit, absorbs rf energy each...
4042923 Radar trilateralization position locators  
A radar position locator system uses a mobile and at least two stationary transceivers. The signals are validated by being stored and compared with previously received signals. If the comparison...
4040053 Transponder system for the transfer of signalling information for rail-bounded vehicles  
A transponder system with ensured synchronization for a railway signalling system, comprising an interrogating station, from which an interrogation signal is transmitted continuously, and a...
4038653 Train position indicator  
A low power radar mounted on the train interrogates passive transponders located along the track. Inductive coupling arrangements associated with the radar and each of the transponders inhibits...
4027840 Vehicle position indicator with radar interrogation each of spaced transponders disposed along a pathway for the vehicle  
This invention applies to an automatic train control system. A low power radar mounted beneath a train interrogates simple passive transponders mounted between the rails. Each transponder includes...
4023167 Radio frequency detection system and method for passive resonance circuits  
A system for detecting passive resonant circuits in which bursts of swept radio frequency are transmitted to excite passive resonant circuits. If a circuit is resonant at a particular burst...
4019181 Transponder system  
A responder system in which incoming frequency f 0 is converted to a harmonic frequency, e.g. 2f 0 , by means of a non-linear element, for example a diode, which is connected between capacitance...
3970824 Electronic recognition and identification system for identifying a family of codes  
An electronic recognition and identification system for recognizing and identifying any one of a family of electrically-coded external objects. The system comprises internal electronics including a...
3967202 Data transmission system including an RF transponder for generating a broad spectrum of intelligence bearing sidebands  
A data transmission system for obtaining information from a plurality of data sources includes an interrogate source for transmitting RF interrogate signals to the locations of the data sources and...
3934250 Helicopter blind landing and hover system  
A precision hover and landing system for use in a helicopter is provided. A elevision camera system, an infra-red scanner and a passive radar antenna array are located on a three-axis gimbal...
3931622 Voice-modulated transponder system  
A voice-modulated transponder system comprising an interrogator and a light-weight transponder. In the described embodiment, the interrogator is airborne and the transponder is located on the...
3919708 Ranging systems  
A two-way ranging system in which a first station transmits a signal and decodes this transmission to provide a first measured time, a second station receives the transmission, decodes the signals...
3913100 Device for decoding pulse-coded data  
A decoder device for decoding binary codes words each formed by a sequence of (n-1) logic conditions at a clock period θ. The code words are contained within a pair of "frame" pulses. A high clock...
3870994 GEOGRAPHIC ADDRESSING BY INTERROGATION FOR CONTROLLING AIRPORT GROUND TRAFFIC  
The geographical location of on-the-ground traffic having on-board ATC transponders can be specifically addressed through the use of two spaced apart interrogators. A first interrogator transmits a...
3859652 METHOD AND APPARATUS FOR DETECTING THE THEFT OF ARTICLES  
The theft of articles or goods maintained in a vending place such as a department store having at least one exit passageway is prevented by affixing thereto a preferably small detection element...
3824469 COMPREHENSIVE AUTOMATIC VEHICLE COMMUNICATION, PAGING, AND POSITION LOCATION SYSTEM  
A comprehensive electronic communication system for vehicles to permit transmission and reception of signals with respect to traffic warnings, crash warnings, emergency location signals, assistance...
3805264 INQUIRY-REPLY SYSTEM IN PARTICULAR SECONDARY RADAR DEVICE  
An inquiry-reply system utilizing a primary inquiry antenna which has a distinctive main lobe radiation pattern and less distinctive and smaller side lobes. An additional antenna is provided which...
3798642 RECOGNITION SYSTEM  
A recognition system comprising a transmitter for radiating an amplitude modulated signal to a target that generates a harmonic of the received signal, detects the amplitude modulating signal and...
3792471 RADAR RANGE LOCK LOOP  
There is disclosed a radar tracking system wherein a range measurement is obtained by measuring the interval between the transmission of an interrogating pulse and the receipt of a reply pulse from...
3772668 FREIGHT SECURITY SYSTEM  
An electronic security system for safe-guarding freight against theft while in transit and/or while sitting at a dock site. The concept of the system is to plant a unique transceiver in the freight...
3772693 SECONDARY RADAR RANGING SYSTEMS  
A system for assisting the berthing of large ships measures their range and aspect relative to the berth and includes two master radars on the ship and two radar transponders at the berth and means...
3755814 PRECISION TRANSPONDER SYSTEM  
A gas discharge tube is placed in the transmission line of a radar to briy interrupt the transmitted signal to form a notched pulse that is transmitted to a transponder. The notching is reproduced...
3729736 CODE REGENERATIVE CLEAN-UP LOOP TRANSPONDER FOR A μ-TYPE RANGING SYSTEM  
A loop transponder for regenerating the code of a μ-type ranging system is disclosed. It includes a phase locked loop, a code generator and a loop detector. The function of the phase locked loop...
3725786 SYSTEM FOR DISCRETE MARKING AND DETECTING A PREDETERMINED POINT IN TIME WITHIN THE ENVELOPE OF A PULSE MODULATED CARRIER  
The radiator pulse of an aircraft distance measuring equipment is characterized by a radio frequency phase reversal at its mid-point in time, hence producing a sharp cusp of zero amplitude which is...
3714650 VEHICLE COMMAND AND CONTROL SYSTEM  
A dual frequency ranging and communication system for communicating with and locating mobile vehicles in a multipath environment such as an urban center. This system functions in urban areas for...
3713148 TRANSPONDER APPARATUS AND SYSTEM  
A novel transponder apparatus and system is disclosed, the system being of the general type wherein a base station transmits an "interrogation" signal to a remote transponder, the transponder...
3710382 SECONDARY RADAR  
To increase the data rate of a mechanically scanning radar aerial, two aerials on a common support share a common rotating joint to which they are alternately switched under remote control,...
3701150 RF TRANSMISSION AND DETECTION SYSTEM  
An interrogation station includes a master frequency oscillator controlled to perform as an FSK oscillator for the transmission of data from the interrogation station. In addition this oscillator...
3689885 INDUCTIVELY COUPLED PASSIVE RESPONDER AND INTERROGATOR UNIT HAVING MULTIDIMENSION ELECTROMAGNETIC FIELD CAPABILITIES  
An interrogator-responder system wherein the responder is a passive responder receiving an inductively coupled electromagnetic power field from an interrogator unit and generating an unique...
3631442 ANTI-SHOPLIFTING SYSTEM  
Article theft detection system wherein a passive nonlinear radio transponder is attached to each article to be protected, and an exit way is monitored by a loop antenna which is energized by...
3546695 RADAR TRANSPONDOR SYSTEM  
3427612 AIR TO GROUND RADAR TARGET IDENTIFICATION SYSTEM  
3384892 Interrogator-responder signalling system  
3380049 Method of resolving clock synchronization error and means therefor  
3312971 Radar system  
3184737 Radar system  
3161872 Beacon radar recording and reproducing  
3097348 Secure communication system  
3087151 Proximity warning or position separation device  
Matches 351 - 400 out of 406 < 1 2 3 4 5 6 7 8 9 >