Matches 301 - 350 out of 406 < 1 2 3 4 5 6 7 8 9 >
Match Document Document Title
5414427 Device for information transmission  
A device for information transmission, a so-called transponder, for receiving a first microwave signal, modulating and coding, and retransmitting a second microwave signal, having at least one...
5396251 Electronic transponder tuning procedure  
A method is disclosed herein for tuning a responder unit (12). The method comprises the steps of storing energy in a responder unit energy accumulator (136) in a contactless fashion by RF energy...
5392049 Device for positioning a first object relative to a second object  
A device for positioning a first object relative to a second object, primarily for positioning an automatic fuelling device relative to vehicles. A transponder using a microstrip antenna design is...
5379042 Method of storing data relating to the life of a complicated product  
A method for storing the life data of complicated products, primarily different types of automotive product, particularly cars, by the contactless transmission of information between a...
5374930 High speed read/write AVI system  
A transponder (14) for communicating with an interrogator (12) has a high Q-factor resonant circuit (34) of frequency f 1 for receiving RF powering signals. The transponder also has a tuning...
5361071 Microwave identification system  
A microwave identification system comprising a transmitter/receiver provided with an antenna system, a plurality of responders provided with an antenna system, the communication between...
5357254 Location monitoring system  
A location monitoring system is provided having a radio frequency transmitter for a person or object and radio frequency receiver for someone to monitor movement of the person or object, the...
5355137 Method of reading the data stored in a passive responder by means of an interrogation device comprising a receiving section  
A method is described for reading the data stored in a passive responder (20) by means of an interrogation device (10) including a receiving section (14). To initiate a read cycle the interrogation...
5349355 Credential tracking system  
A microwave carrier signal emitted from a tracker unit is amplitude moduld periodically at different preset modulation frequencies during spaced intervals between established time slots. The...
5347280 Frequency diversity transponder arrangement  
A method of communicating between a transponder and an interrogator. The interrogator (10) transmits a wireless RF interrogation which is received by the transponder (12). The transponder (12) then...
5305469 Modem for telecommunication system with a reflection amplifier function  
A modem which is to be included in a badge or mobile station, in a system for the exchange of data by microwaves with a fixed station or beacon. The modem has at least one transistor that works as...
5298904 Distance measuring system  
A distance measuring system which may be used on a golf course in order for a golfer to accurately measure the distance between the present lie of his golf ball and the hole toward which he is...
5258762 Identification system using hertzian waves, consisting of an interrogation station and a responder unit  
Identification system constituted by an interrogation station or interrogator 1 itself formed by a radio frequency wave transceiver and preferably on an ultra frequency wave length 5, and, on the...
5245346 Interrogator/transponder system and mobile transponder device  
An interrogation responder system composed of a transmitter stationarily mounted in a certain fixed place and a receiver mounted on a mobile object. The receiver on the mobile side starts the...
5233353 System for measuring the distance between two stations mobile with regard to one another  
An emitted wave is transmitted from a central station to a passive end. A phase modulation circuit in the passive end modulates a signal resulting from the emitted wave for retransmitting it in the...
5196846 Moving vehicle identification system  
A system for exchanging information by means of transmitted RF signals between a fixed location interrogator and a vehicle transponder moving in the vicinity of the interrogator. The transponder...
5192954 Roadway antennae  
Antennas designed for use in producing effective electromagnetic capture zones for transponders mounted on moving vehicles. The antenna systems disclosed are principally designed to be mounted at...
5173705 Telecommunications device using electromagnetic waves  
The disclosure relates to the field of data exchange by microwaves between a fixed station, or reader, and a mobile station, or badge. To achieve economy in the energy consumption of the badge,...
5159344 Aircraft theft detection and location system  
A theft detection and location system for aircraft utilizing both a conventional aircraft transponder/encoder and a dedicated transponder/encoder. The dedicated transponder is fixed on an alarm...
5144312 Locating system  
A system for locating a transponder (10) to an accuracy of plus or minus about 10 m in an area about 5 km across includes a master station (12) and two slave stations (14, 16) at known positions....
5144313 Method for processing transmitted and reflected signals for removing unwanted signals and noise from wanted signals  
In an identification system based on reflection of radar signals from a bit-coded transponder, the received signals are processed to remove unwanted signals and noise from the required, reflected...
5140328 Virtual secondary surveillance radar using signals of remote SSR  
A virtual secondary surveillance radar (VSSR) of the type described in U.S. Pat. No. 4,115,771 can produce inaccurate or indeterminate range information for a transponder positioned on or near a...
5128669 Communicating information by radio  
Information is communicated by microwave radio between transponders (9,10) carried by vehicles (7,8) travelling on a road (1) and a station (22) adjacent the road. The communications from the...
5072222 Electromagnetic identification and location system  
An electromagnetic identification and location system is described. The system comprises at least one interrogator which, in operation, generates an electromagnetic interrogation field by at least...
5003600 Diffraction gratings used as identifying markers  
A finely detailed defraction grating is applied to an object as an identifier or tag which is unambiguous, difficult to duplicate, or remove and transfer to another item, and can be read and...
5001486 Radar system for determining the position of two or more objects  
A radar system operating by the line-of-sight method requires an accurate measurement of the relative position of at least two objects. By sending out coded radar transmission pulses, control data...
4983976 Signal transmission system and method  
A data transmission system includes a data carrier which has a memory for storing therein data including an identification code and which is attached to an object and a main apparatus having a...
4965583 Collision avoidance system for automatically controlled vehicles moving at short headways  
Safe separation distances between automatically controlled vehicles moving at short headways on a guideway are maintained through the cooperative action of a block control system and reflectometer...
4963887 Full duplex transponder system  
A full duplex transponder system includes an interrogation apparatus and a transponder apparatus. The transponder apparatus includes a reception antenna for receiving an interrogation signal wave...
4918458 Secondary radar transponder  
A secondary radar transponder on a mobile target has an antenna arrangement which can receive interrogation signals from all directions and radiate reply signals. The antenna arrangement includes...
4908627 Monitoring, ranging and locating devices  
Two miniaturized transceivers, each selectively responsive to predetermined radio frequency (r.f.) transmissions which may be coded, consisting of one control unit and one transponder unit....
4890111 Passive transponder  
The antenna elements of the transponder of this invention are pierced with openings and thus have a general form of loops surrounding spaces devoid of any metallic elements. This arrangement...
4864306 Railway anticollision apparatus and method  
A railway anticollision apparatus and method is disclosed in which machine readable trackside markers such as bar code markers are utilized along the track and are read by apparatus on board the...
4818998 Method of and system and apparatus for locating and/or tracking stolen or missing vehicles and the like  
An improved vehicle or other object-tracking and location system, preferably, though not essentially, of national scope, wherein transponder or transceiver-equipped stolen or missing vehicles or...
4804961 Method and apparatus for measuring distances  
A method for measuring the distance between a first object, which incorporates a transmitter-receiver unit, and a second object, which incorporates a transponder. In accordance with the invention...
4728955 Method for position-finding and apparatus herefor  
A method for determining a mutual position between two objects, comprising transmitting a microwave signal from the first object towards the second object, causing the second object to receive the...
4706091 Cockpit transmission assembly  
An audio signal transmission system to be used on commercial airlines for the discrete transmission of voice conversations emanating from the cockpit of the aircraft automatically to a ground...
4698633 Antennas for wide bandwidth signals  
A system for transmitting and receiving very wide instantaneous bandwidth signals. Synchronized short pulse generators are positioned at the feed location of each element of a linear array of short...
4686517 Field disturbance detection system  
An electromagnetic detection system is described which, in operation, in a detection zone, by means of at least one transmission antenna coil, generates a swept-frequency interrogation field...
4684949 VHF/radar transponder collision avoidance aid  
A radiotelephone and a radar transponder are interconnected in such a manner as to establish a VHF communications link via the radiotelephone in response to interrogation of the radar transponder....
RE32368 Collision avoidance system for aircraft  
A collision avoidance system for aircraft in which one aircraft is equipped with an interrogation station having a secondary surveillance radar. Coarse A distance measurement is effected either...
4631708 Transmitter/responder systems  
A memory suitable for use as a responder, comprising: (a) receiver means for receiving a transmitted signal S1; (b) generator means (76) for generating a carrier component of a transmittable...
4622557 Transdigitizer for relaying signals from global positioning system (GPS) satellites  
The reception, downconversion and retransmission of the 1575.42 MH z Global Positioning System (GPS) satellite signal is accomplished by the following. First, an RF stage comprising of an antenna,...
4609922 Apparatus for controlling and for signal transmission in conveyor installations  
Transponders are arranged at control locations associated with sections of a track or travel path. Each transponder is in wireless communication through an inductive transmission path and an...
4551712 Electronic detection system for detecting a responder including a frequency divider  
In an electronic detection system comprising a transmitter for generating an interrogation field, said transmitter being coupled with at least one transmitting antenna coil; a responder with a...
4476459 Theft detection method and apparatus in which the decay of a resonant circuit is detected  
In an electronic theft detection apparatus the passage of a resonant circuit wafer 16 through an interrogation zone formed by transmitter and receiving antennas (30, 90) (32, 92) is detected by...
4471344 Dual frequency anti-theft system  
An article surveillance system employs a label or tag containing a non-linear impedance element, such as a semiconductor diode, connected to a metal antenna loop configured to pick up two distinct...
4373159 Heat and detection resistant identification apparatus  
An identifier such as a strip of heat resistant metal, containing preselected identifying information in the form of an alpha-numeric serial number is concealingly retained in a carrier member. The...
4370653 Phase comparator system  
An improved interrogation means in a range finding system having signal generating means for generating interrogation signals having a first encoded portion and a first basic tone portion. A...
4350982 Frequency-agile transponder  
A compact transponder for use with frequency-agile pulsed radars incorporng an Amplified Ferromagnetic Echo Device (AFED) which repeats, backwards, after a short and controllable delay, a microwave...
Matches 301 - 350 out of 406 < 1 2 3 4 5 6 7 8 9 >