41 results about "Spurline" patented technology

In an exemplary embodiment, a spurline filter comprises a capacitive element connected to a spur and either a through-line of the spurline filter or ground. In another embodiment, multiple capacitive elements are connected to the spur. In an exemplary embodiment, the capacitively loaded spurline filter provides a band rejection frequency response similar to the band rejection frequency response of a similar spurline filter that does not comprise at least one capacitive element but the capacitively loaded spurline filter has half the layout area or less. In an exemplary embodiment, the spurline filter comprises capacitive elements, where the capacitive elements are configured to reduce the resonant frequency of the filter.

A microwave filter is provided that includes a transmission line having a signal input port and a signal output port, a stub connected to the transmission line between the input port and the output port, and a spurline embedded in the stub. The microwave filter is configured to substantially attenuate a frequency while substantially passing at least one predetermined odd harmonic of the frequency.

A bandpass filter passes a range of frequencies with low loss while suppressing frequencies above and below the passed range of frequencies. One or more spurlines is included into the existing structure of the bandpass filter so that a selected odd multiple of the passed frequency range is suppressed.

A bandpass filter passes a range of frequencies with low loss while suppressing frequencies above and below the passed range of frequencies. One or more spurlines is included into the existing structure of the bandpass filter so that a selected odd multiple of the passed frequency range is suppressed.

The invention discloses a double-dimension reconfigurable orthocoupler. The double-dimension reconfigurable orthocoupler comprises a dielectric plate, an improved branch coupler, a frequency modulation bias unit and a power-division-ratio adjusting bias unit, wherein the improved branch coupler adopts a matts structure and consists of a basic branch line coupler and crossed-shaped microstrip lines; the frequency modulation bias unit consists of four frequency modulation bias circuits; the power-division-ratio adjusting bias unit consists of two power-division-ratio adjusting bias circuits, wherein a first microwave signal is accessed to the input port of the basic branch line coupler; each frequency modulation bias circuit adjusts equivalent electrical lengths of series arms and parallel arms based on a first preset bias voltage and the first microwave signal; meanwhile, each frequency modulation bias circuit adjusts equivalent impendence of the parallel arms based on a second preset bias voltage and the first microwave signal; and the output port outputs a second microwave signal with a preset center frequency and preset power-division ratio. Based on the double-dimension reconfigurable orthocoupler, continuous adjustment of the center frequency and the power-division ratio is realized, and the purposes of reconfigurable center frequency and power-division ratio, signal quadrature output and easy processing are achieved.

A method and a system for reading radio frequency identification (RFID) tags are provided. The method includes the following steps. First, receive a tag signal from the RFID tag. Recover a data clock rate from the tag signal according to statistics of pulse lengths of the tag signal. Next, determine a frame synchronization point of a data frame following a preamble in the tag signal by a signal correlation between the preamble and a predetermined signal pattern according to the data clock rate. Finally, decode the data frame by using an adaptive Viterbi algorithm on an extended trellis diagram. The extended trellis diagram includes a plurality of nodes and a plurality of branches connecting the nodes. The nodes and the branches are arranged according to the modulation scheme of the data frame and possible variations of the data clock rate.

The invention discloses a UHF frequency band passive RFID high-separation dual-frequency transceiver separator, which includes a microstrip coupling line directional coupler, a transmitter port, a receiver port, a load port and an antenna port, and is characterized in that it also includes an absorption resistor, a micro One of the strip line segments, the second of the microstrip line segment, one of the open branch lines, the second of the open circuit branch lines, the third of the open circuit branch lines and the microstrip open line, one end of one of the microstrip line segments and one end of one of the open circuit branch lines Connected to the load port, the other end of one of the microstrip line segments is connected to one end of the open circuit branch line two and one end of the microstrip line segment two, the other end of the microstrip line segment two is connected to one end of the open circuit branch line three and the absorption resistor One end of the snubber resistor is connected to one end of the microstrip open line. The invention can simultaneously realize the high-separation separation of RFID transceiving signals on two frequency bands, and improve the working distance of the RFID reader-writer.