6 results about "Insertion loss" patented technology

A piezoelectric substrate and interdigital electrode portions are covered with an insulating layer with an insulating thin film interposed therebetween. The piezoelectric substrate is made of LiTaO₃ and the insulating thin film and the insulating layer are made of silicon oxide. By intentionally making the upper surface of the insulating layer flat, the deterioration of propagation efficiency of surface acoustic waves can be suppressed, so that it is possible to reduce increase in insertion loss of a resonator. Since the upper surface of the insulating layer is flat, it is also possible to reduce variation in resonant frequency and anti-resonant frequency due to the temperature change of the surface acoustic wave device.

The invention provides a piezoelectric acoustic wave resonator. The shape of an effective working area of the piezoelectric acoustic wave resonator is a polygon, a first side and a second side in theeffective working area correspond to an input side and an output side of the piezoelectric acoustic wave resonator respectively, and an outer frame of the effective working area is defined as a rectangle which can surround the effective working area and has the smallest area where one side coincides with the first side or the second side; one side of the outer frame that coincides with the first side or the second side has a first length, one side of the outer frame that is perpendicular to the side has a second length, and the ratio range of the first length to the second length is 1-4; and the ratio range of the sum of the lengths of the first side and the second side to the circumference of the effective working area is 0.4-0.7, wherein the ratio ranges of the lengths of the first sideand the second side to the circumference of the effective working area are both 0.2-0.35. The invention also provides a piezoelectric acoustic wave filter, a duplexer and a radio frequency communication module. Through the implementation of the invention, the electrical transmission loss of the piezoelectric acoustic wave resonator can be improved, and the insertion loss of the piezoelectric acoustic wave filter can be further improved.

The invention discloses an optical fiber insulator insertion loss detector, which comprises an SLD light source, a light source driving module, a beam splitter, a first emergent optical fiber, a second emergent optical fiber, an incident optical fiber, an AD acquisition circuit and an output display device, wherein the beam splitter can split inputted light signals into two beams of light signals whose intensity ratio is close to 1 to 1 and output the light signals; the AD acquisition circuit is provided with a first light power measurement module and a second light power measurement module which can measure light power of the inputted light signals and output light power measurement values by using digital signals; and the output display device records a light power measurement value outputted by the first light power measurement module as an input light power value, records a light power measurement value outputted by the second light power measurement module as an output light power value, calculates the insertion loss of a detected optical fiber insulator and displays the insertion loss in real time. The optical fiber insulator insertion loss detector can realize detection and display on the input light power value, the output light power value and the insertion loss of the detected optical fiber insulator, and has the advantages of precise measurement, easy operation, and convenient calibration.

The invention discloses a return loss measuring method of optical devices, which comprises the following steps: step 1: a three-port optical fiber circulator is prepared, the second port of the three-port optical fiber circulator is connected with one laser source, the third port of the three-port optical fiber circulator is connected with a standard optical power meter, and the insertion loss of device optical power from the second port to the third port is measured; step 2: the first port of the circulator is connected with the other laser source, the second port is connected with a measured optical device, the third port is connected with the standard optical power meter, and power of the light that is reflected by the measured optical device is measured; step 3: the optical power loss of a node S between the second port of the optical fiber circulator and the measured optical device is measured; step 4: the return loss of the measured optical device is calculated.

The invention provides an epoxy potting inductor and a fabrication method thereof. The epoxy potting inductor comprises an annular iron core, an inductance coil, an unsintered tape, epoxy resin and a housing, wherein the inductance coil is wound on the annular iron core; the unsintered tape is wound on the annular iron core and coats the inductance coil; the annular iron core is accommodated into the housing; and the epoxy resin is added between the inner wall of the housing and the outer wall of the unsintered tape. According to the epoxy potting inductor, the wound inductance coil and the annular iron core are potted in a shell after being coated with the unsintered tape, so that important parameters of distributed capacitance, insertion loss, a Q value and the like of the inductance coil before and after being potted can be kept constant; interference to the parameters of the inductance coil caused by stress and dielectric loss of potting epoxy resin is avoided; and the energy efficiency, the waveform and the EMC (electromagnetic compatibility) of a complete machine meet related requirements.

The invention discloses a novel surface acoustic wave or transverse wave exciter acoustic-microwave device chip structure. The chip structure comprises a surface acoustic wave or transverse wave exciter acoustic-microwave device chip circuit and a chip substrate; a first groove and a second groove are arranged in the chip substrate; a first piezoelectric material is filled in the first groove; a first electrode is arranged on the first piezoelectric material; one end of the first electrode is connected with the first piezoelectric material; the other end of the first electrode is connected with the signal input end of the chip circuit; a second piezoelectric material is filled in the second groove; a second electrode is arranged on the second piezoelectric material; one end of the second electrode is connected with the second piezoelectric material; and the other end of the second electrode is connected with the signal output end of the chip circuit. By means of the novel surface acoustic wave or transverse wave exciter acoustic-microwave device chip structure provided in the invention, the transmission loss and microwave insertion loss of the device can be reduced; and the performances of the device, such as the frequency and the quality factor, can be improved.