Abstract:
A signal processing circuit has a first signal loop with a first signal processing block and a first feedback path that extends around the first signal processing block, the first signal processing block having a frequency dependence that causes the first signal loop to generate a passband. A second signal processing block is downstream of the first signal loop. A second feedback path extends from downstream of the second signal processing block to upstream of the first signal processing block. In operation, the first feedback path reinforces a signal in the passband and the second feedback path conditions the signal at an output downstream of the first signal processing block.
Abstract:
A radio frequency (RF) MEMS resonator is embedded in an active positive feedback loop to form a tunable RF channel-selecting radio transceiver employing a super-regenerative reception scheme. This transceiver harnesses the exceptionally high Q (around 100,000) and voltage-controlled frequency tuning of a resonator structure to enable selection of any one of among twenty 1 kHz wide RF channels over an 80 kHz range, while rejecting adjacent channels and consuming
Abstract:
A cancellation-based filter may have at least one frequency pass band and at least one frequency stop band. The cancellation-based filter may include a first group of one or more band pass filters, each having at least one acoustic resonator, the first group providing at least one frequency pass band for the cancellation-based filter; at least one hybrid coupler; and a second group of one or more band pass filters, each having at least one acoustic resonator, the second group coupled to at least one of the at least one hybrid couplers, wherein the at least one hybrid coupler and the second group of one or more band pass filters interact to provide at least one frequency stop band for the cancellation-based filter.
Abstract:
A micro-electromechanical resonator includes a resonator body having a semiconductor region therein doped with boron to a level greater than about 1x1018 cm-3 and even greater than about 1x1019 cm-3, in order to obtain reductions in the temperature coefficient of frequency (TCF) of the resonator over a relatively large temperature range. Still further improvements in TCF can be achieved by degenerately doping the resonator body with boron and/or by boron-assisted aluminum doping of the resonator body.
Abstract translation:微机电谐振器包括谐振器本体,其具有其中掺杂有硼的半导体区域,其水平大于约1×10 18 cm -3且甚至大于约1×10 19 cm -3,以便获得频率温度系数(TCF )在相对较大的温度范围内。 可以通过用硼简谐掺杂谐振器体和/或通过谐振器体的硼辅助铝掺杂来实现TCF的进一步改进。
Abstract:
An electronic filter (100) comprising: a filter section (102, 104); an impedance correction section (106 and 108) that is electrically coupled to the filter section (102, 104); and a circuit altering section (110-116) that is arranged to alter at least one property of the impedance correction section (106, 108) to effect a shift in a resonant frequency of the impedance correction section (106, 108) from with a pass band of the filter section to within a stop band of the filter section (102, 104).
Abstract:
A MEMS filter has an input layer for receiving a signal input, and an output layer for providing a signal output, The MEMS filter also has a first resonator and a second resonator coupled to the first resonator such that movement transduced in the first resonator by the signal input causes movement of the second resonator which transduces the signal output. A method of manufacturing a MEMS filter is also disclosed. A dielectric layer is formed on a base. A patterned electrode layer is formed at least in part on the dielectric layer. The base is etched to define a resonator structure. A method of adjusting a desired input impedance and an output impedance of a dielectrically transduced MEMS filter having transduction electrodes coupled to a dielectric film is further disclosed. The method includes adjusting a DC bias voltage on the transduction electrodes.