661 results about "Pulse repetition frequency" patented technology

A data-modulated ultra wideband transmitter that modulates the phase, frequency, bandwidth, amplitude and / or attenuation of ultra-wideband (UWB) pulses. The transmitter confines or band-limits UWB signals within spectral limits for use in communication, positioning, and / or radar applications. One embodiment comprises a low-level UWB source (e.g., an impulse generator or time-gated oscillator (fixed or voltage-controlled)), a waveform adapter (e.g., digital or analog filter, pulse shaper, and / or voltage variable attenuator), a power amplifier, and an antenna to radiate a band-limited and / or modulated UWB or wideband signals. In a special case where the oscillator has zero frequency and outputs a DC bias, a low-level impulse generator impulse-excites a bandpass filter to produce an UWB signal having an adjustable center frequency and desired bandwidth based on a characteristic of the filter. In another embodiment, a low-level impulse signal is approximated by a time-gated continuous-wave oscillator to produce an extremely wide bandwidth pulse with deterministic center frequency and bandwidth characteristics. The UWB signal may be modulated to carry multi-megabit per second digital data, or may be used in object detection or for ranging applications. Activation of the power amplifier may be time-gated in cadence with the UWB source thereby to reduce inter-pulse power consumption. The UWB transmitter is capable of extremely high pulse repetition frequencies (PRFs) and data rates in the hundreds of megabits per second or more, frequency agility on a pulse-to-pulse basis allowing frequency hopping if desired, and extensibility from below HF to millimeter wave frequencies.

The present invention describes a network communication system which includes a first slave transceiver configured to communicate a plurality of TDMA data packets at different data rates to a second slave transceiver. The second slave transceiver is also configured to communicate a plurality of TDMA data packets at different data rates to the first slave transceiver. A master transceiver manages data communications between the first slave transceiver and the second slave transceiver. Each transceiver includes a data modulation unit, a transmitter, an antenna, and a receiver. The data modulation unit is configured to generate a plurality of signals having variable pulse repetition frequencies and different modulation techniques. The transmitter is coupled to the data modulation unit and the transmitter is configured to generate a pulse stream according to the data modulation unit. The transmitting antenna is coupled to the transmitter and the transmitting antenna is configured to transmit a plurality of ultra wide band base band signals. The receiver is configured to detect and demodulate said ultra wide band base band signals operating at variable pulse repetition frequencies and having different modulation methods.

The present invention is a receiver having a radio frequency (RF) front end, a pulse detector operatively coupled to the RF front end, and a data recovery unit operatively coupled to the pulse detector. The data recovery unit is configured to receive spread spectrum RF signals having different pulse repetition frequencies and using different modulation techniques. The receiver may operate in conjunction with a transmitter as a transceiver. The receiver may also operate in a networked environment in which a network of transceiver node devices comprise a first slave transceiver having a receiver configured to receive spread spectrum signals, and a second slave transceiver configured to communicate with the first slave transceiver. Additionally, a master transceiver is in communication with the first slave transceiver and the second slave transceiver. The master transceiver is configured to manage data transmissions and synchronization between the first slave transceiver and the second slave transceiver.

An active radio frequency identification (REID) tag implemented on a flat label. The tag includes a battery printed on the label, a flat wide-band antenna printed on the label and a wide band communication circuit implemented as a chip inlay inside the label. The circuit is attached to the battery and to the antenna. The combined thickness of the battery, the antenna and the circuit as printed on the flexible label is less than one millimeter. The battery, the antenna and the circuit are printed on the label so as to render substantial flexibility to the RFID tag. The circuit operates at a center frequency of at least one gigahertz and a bandwidth at least twenty percent of said center frequency or a bandwidth at least 500 Mhz. The tag typically includes an inaccurate clock source such as an RC circuit and does not include a crystal. Average power consumption of the battery is preferably reduced by operating the tag with a low duty ratio between an active and an inactive interval; and during the active interval transmitting in bursts while turning off parts of the tag between the bursts. The communications circuit performs timing measurements on incoming received waveforms and transmits transmit signals in response to the received waveforms with timing based on the timing measurements. The receiver circuitry locks on a repetition frequency of the incoming received waveforms, and based on the repetition frequency generates a pulse repetition frequency of the transmit signals.

Laser direct ablation (LDA) produces patterns cut into a dielectric layer for the formation of electrically conductive traces with controlled signal propagation characteristics. LDA processing includes selecting a dose fluence for removing a desired depth of material along a scribe line on a surface of a workpiece, selecting a temporal pulsewidth for each laser pulse in a series of laser pulses, and selecting a pulse repetition frequency for the series of laser pulse. The pulse repetition frequency is based at least in part on the selected temporal pulsewidth to maintain the selected dose fluence along the scribe line. The selected pulse repetition frequency provides a predetermined minimum overlap of laser spots along the scribe line. The LDA process further includes generating a laser beam including the series of laser pulses according to the selected dose fluence, temporal pulsewidth, and pulse repetition frequency.