Match Document Document Title
5748139 Radar transponder  
A radar transponder for a stable and reliable response transmission upon reception of a weak radar signal having a reflection-conscious circuitry free from damage by a transmit effect, including a...
5745049 Wireless equipment diagnosis system  
A wireless equipment diagnosis system which can perform inspection and maintenance precisely and accurately, and which comprises sensors which measure information on each equipment being...
5742895 Device for transmitting and receiving information signal in multimedia communication system  
A device used in a multimedia communication system is formed with a transceiver unit for transmitting and receiving information signal to and from the inside of a room and a base unit adapted to...
5734965 On-board unit for transponder operation  
An on-board unit includes at least one receiving and transmitting antenna for a bidirectional transmission of data which works in accordance with the transponder method. To compensate for...
5731957 Transponder including a fluid cushioning medium and a method for its production  
Transponder A,B! formed of a bottom-closed elongate tubular enclosure 12! having a mouth 12'! at an upper end and circuit-receiving space within the enclosure for fully receiving an electronic...
5721552 Transponder with AGC regulator  
For the digital data communication between a vehicle (transponder) and a beacon, an automatic gain control wherein the path attenuation between the transponder and the brake increases...
5717390 Doppler-radar based automatic vehicle-classification system  
A method for automatically categorizing the general variety of motor-vehicle types moving through a given checkpoint, according to their predominant characteristics; basically involving features...
5712630 High power moving object identification system  
A moving object identification system with a novel coding scheme achieves 75% transmission efficiency. With this system, a transmittable range is expanded. Logical value assignment for residual...
5712628 Digitally programmable radio modules for transponder systems  
A programmable digital radio is configured to perform transponder functions. A receiver in the programmable digital radio receives analog signals from an interrogator and digitizes the analog...
5708972 Vehicle communication system and method providing high responsivity to multiple polling units  
To enable communications between a vehicle-installed device and an antenna unit even when the vehicle-installed device passes through an area where neighboring communication areas overlap each...
5703574 Method and device for transferring a measurement signal from a revolving roll used in a paper making machine  
A method and device for transferring a measurement signal from a revolving roll used in a paper making machine, in which detectors are arranged in the transverse direction of the roll, preferably...
5701127 Automatic vehicle identification system capable of vehicle lane discrimination  
A method of identifying an object and determining in which of at least two areas the object is located is disclosed. The method includes the steps of: focusing a first directional antenna (18) on...
5699066 Synchronized electronic identification system  
The invention relates to an identification system comprising an interrogator and a plurality of transponders. The interrogator includes transmitter means for transmitting an interrogation signal...
5691698 Identification and/or sensor system  
An identification and/or sensor system includes an identification and/or sensor configuration having resonators for determining at least one parameter to be interrogated. The resonators have a...
5689263 Antipilferage markers  
An antipilferage tag is disclosed which includes a resonant circuit adapted to receive an RF signal and to transmit a response signal when interrogated by said RF signal. The tag includes circuit...
5689266 Testing apparatus for ATC transponder FAR compliance  
Airplanes have transponders which receive and transmit signals to communicate information regarding the flight of the airplane. A transponder testing apparatus is integrated into the transponder...
5686920 Transponder maintenance mode method  
A method and system is provided for communicating permanent or semi-permanent information to a transponder (14) from an interrogator (12), preferably operated by a toll agency or other authorized...
5682603 Start-up method for mobile transceivers, mobile transceivers and fixed transceivers thereof  
To provide a communications system to accurately detect when a mobile transceiver has entered an area where communication with a fixed transceiver is possible, and to start-up the internal...
5680106 Multibit tag with stepwise variable frequencies  
A transponder is disclosed comprising a resonant RLC circuit with one or more components that can be connected or disconnected non-destructively using switches that respond to an externally...
5657008 Electronic license plate having a secure identification device  
A electronic license plate system having an identification device embedded in a license plate portion and electronics stored in a license plate holder ensures that the proper identification device...
5648767 Transponder detection system and method  
A transponder detection system for detecting the presence at a detection area of a vehicle on which the transponder is mounted. Two antenna arrays are located on opposite sides of the detection...
5649296 Full duplex modulated backscatter system  
A duplex radio communication system includes an Interrogator which generates a first modulated signal by modulating a first information signal onto a radio carrier signal. The Interrogator...
5649295 Dual mode modulated backscatter system  
A radio communication system includes an Interrogator for generating and transmitting a first modulated signal by modulating a first information signal onto a radio carrier signal, the first...
5642103 Transponder used in a remote identification system  
A transponder used in a remote identification system requiring an interrogator and a transponder. The transponder which is thin and compact includes a transmit/receive antenna which is thin for...
5642358 Multiple beamwidth phased array  
A system for wireless communication between at least one first station and a plurality of second stations using a relay station is disclosed. The relay station contains, among other features, an...
5627544 Data communication method using identification protocol  
A protocol is used to coordinate the use of a common communication medium by one or more interrogating commander stations and an unknown plurality of responding responder stations. Each commander...
5621396 Method and apparatus with adaptive transponder plucking  
A method and apparatus with adaptive transponder plucking is provided in which oscillations from a resonant circuit (12 and 14) are maintained by coupling power from a capacitor (18) through a...
5621411 Positioning with RF-ID transponders  
A method of determining the exact location of a transponder with respect to a reader antenna, with no additional components to the existing system required, is disclosed. An existing pin of the...
5608391 Electronic license plate architecture  
An electronic license plate architecture is described wherein a license plate portion has a conventional license plate having visual information thereon and an identification device integrated...
5608406 Device for controlling discharge of a charge capacitor in a transponder  
A transponder device (10) includes a discharge circuit (18) to control the discharge of voltage from a charge capacitor (14). The discharge circuit (18) prevents transmission of a data telegram by...
5602538 Apparatus and method for identifying multiple transponders  
Apparatus and method of identifying a plurality of transponders (10-16) entering into an inquiry field (18) of an interrogation unit (20) are provided. The transponders (10-16) are each assigned a...
5594447 Moving target identifying system in a base station radar unit for specifying information about moving targets carrying a mobile station radar unit  
A vehicle ID radar system has a simple construction and obtains high identifying performance by making a general identification based on a plurality of responses. There are provided an antenna for...
5592150 Air coil and method of making the same  
In one aspect, the present invention provides an air coil 20. The air coil 20 may be made from a strip of electrically conductive material 22 which has an insulating material overlying it. For...
5587712 Transponder having microprocessor generated frequency shift signals  
An improved transponder for use in identifying an controlling vehicles wherein transponders mounted on vehicles respond to signals from a fixed location interrogator providing information relative...
5579008 Electronic license plate apparatus and method  
Apparatus and method for conveying information from an object by delayed reflection of an interrogating ultra-high range resolution radar signal which is digitized into a series of programmable...
H001606 Electronic quasi-passive identification system  
A quasi-passive identification system having an interrogator and a passive ransponder. The interrogator has a signal generator that generates radio-frequency energy under the control of a manual...
5564069 Communication for a data transmission for a moving vehicle to a stationary beacon  
In a communication system for data transmission from a moving vehicle to a stationary beacon (1) which has a transceiver in which a signal is broadcast by the beacon (1) and received by an antenna...
5557279 Unitarily-tuned transponder/shield assembly  
This invention relates to a shielded transponder 12 which is capable of being mounted on any surface, whether ferromagnetic or not. The transponder includes an antenna which in use is susceptible...
5552790 Device for wireless transfer of information  
A device for wireless transfer of information includes a data carrier in the form of a thin card, and a transponder that receives a first microwave signal, modulates it and codes it with data, and...
5550547 Multiple item radio frequency tag identification protocol  
The present invention uses a novel adaptation of a tree splitting algorithm applied to Radio Frequency (RF) tagging technology to identify many tags in the RF field of a base station.The invention...
5550536 Circuit frequency following technique transponder resonant  
A transponder system (10) includes an interrogation unit (12) that transmits a first frequency F1 representing a binary zero, and a second frequency F2, representing a binary one. These signals...
5546090 Method and apparatus for calibrating antenna arrays  
A method and apparatus for calibrating antenna array systems comprising of a portable transponder (118) and a calibration processor (124). Calibration processor (124) generates calibration...
5543798 Method of providing a synchronized data stream suitable for use in a combined FDX and HDX RF-ID system  
In a method for transmitting a data message comprising a synchronization section and a data section stored in a transponder device (10) to an interrogating device (12) in full duplex mode. The...
5541604 Transponders, Interrogators, systems and methods for elimination of interrogator synchronization requirement  
A Radio Frequency Identification (RFID) system having an interrogator (12) and a transponder (14). The interrogator has a first tuned circuit (28) of a powering frequency for sending a powering...
5537672 System for bidirectional data transmission between a beacon and a vehicle  
A system, for bidirectional transmission of electromagnetic data signals between a stationary unit and a vehicle unit, in which at least two antennas can be used, is proposed. The antennas are...
5525993 Microwave noncontact identification transponder using subharmonic interrogation and method of using the same  
A credit-card sized microwave transponder for "wireless key" and surveillance applications uses a subharmonically-pumped quasi-optical mixer. The transponder is activated by a C-band interrogation...
5525992 Method and system for conserving power in a recognition system  
A system and method for avoiding the discharge of a battery or otherwise excessive power consumption by a transponder (14) in the presence of a spurious noise source. In a described embodiment,...
5525994 Transponder interface circuit  
A transponder interface circuit (172) operates to allow communication between a transponder controller (104) and external circuitry. The interface circuit (172) has a buffer memory (184,186) that...
5521601 Power-efficient technique for multiple tag discrimination  
This invention provides a tag identification system and method for identifying tags in the range of a reader station where the tags are divided into smaller groups, where the tags are identified...
5517195 Dual frequency EAS tag with deactivation coil  
A dual frequency microwave EAS tag includes a dual frequency antenna circuit formed on one side of a substrate. The antenna circuit includes a diode. A deactivation circuit is formed on the other...