摘要:
A voltage regulator includes an amplifier to generate a difference voltage responsive to a comparison of a reference voltage and a feedback voltage. An output driver is coupled to the amplifier and drives a regulated output voltage responsive to the difference voltage. An impedance circuit is coupled between the output driver and a low power source and establishes the feedback voltage responsive to a current through the impedance circuit. A variation detector is operably coupled between the regulated output voltage and the difference voltage and is configured to modify the difference voltage. In some embodiments, the difference voltage is modified responsive to a rapid change of the regulated output voltage capacitively coupled to the variation detector. In other embodiments, the difference voltage is modified responsive to a rapid change of the feedback voltage capacitively coupled to the variation detector.
摘要:
The invention relates to macroporous absorbent resin special for extracting cephalosporin C and process for preparation. Specific surface area of such kinds of adsorbent resins is around 1000-2000 m2/g, pore volume is 1.5-2.5 ml/g. The preparation method is as follows: according to the suspension polymerization to prepare the macroporous copolymer matrix. The mixture of monomer, porogenic agent, initiator of polymerization was put into solution of dissolving some dispersant, then system was heated to 60-100 C.°, and maintained for 5-10 hours, then crosslinked macroporous copolymer matrix is obtained. With the existence of inert medium, the above described macroporous copolymer matrix reacted with Lewis acid as catalyst at 50-120 C.° though the alkylate reaction between the aromatic nucleus. The macroporous absorbent resin special for extracting cephalosporin C descried above possess advantages of high adsorption capacity, good selectivity for target substance, desorption and regeneration easily, and high purity of cephalosporin C can be obtained.
摘要:
A method and apparatus for transmitting an input data signal over an information channel. The input data signal comprises a sequence of data blocks. A puncture coded signal is generated for each data block in the sequence of data blocks. The total number of bits in the puncture coded signal is equal to the number of bits in a particular data block plus additional error correcting bits used to perform error correction at a receiver. The number of error correcting bits is adaptively adjusted for each data block in response to a channel quality measure for the information channel.
摘要:
A voltage regulator includes an amplifier to generate a difference voltage responsive to a comparison of a reference voltage and a feedback voltage. An output driver is coupled to the amplifier and drives a regulated output voltage responsive to the difference voltage. An impedance circuit is coupled between the output driver and a low power source and establishes the feedback voltage responsive to a current through the impedance circuit. A variation detector is operably coupled between the regulated output voltage and the difference voltage and is configured to modify the difference voltage. In some embodiments, the difference voltage is modified responsive to a rapid change of the regulated output voltage capacitively coupled to the variation detector. In other embodiments, the difference voltage is modified responsive to a rapid change of the feedback voltage capacitively coupled to the variation detector.
摘要:
Disclosed herein is a method and apparatus for providing echo cancellation. A plurality of reflections is received. A first strong reflection of the plurality of reflections is selected as a main path. The first strong reflection is then demodulated.
摘要:
A method and apparatus for reducing channel distortion in a broadband, wireless network comprising a residential communications gateway that accepts all incoming communications signals and securely broadcasts those signals throughout a residence. In one embodiment, the gateway comprises a space time block encoder to reduce the effects of multipath and at least one error correction encoder to provide error correction. The space time block encoder generates at least two space time block coded signals that are transmitted via the wireless network. Each space time block coded signal is transmitted using a different antenna.
摘要:
This invention relates to piston compression ring assemblies, each of which consists of a main ring element and an auxiliary ring element. The assemblies can by themselves adjust the radial gaps between the assemblies and the liner, and the gaps between the assemblies and the liner, and the gaps between the assemblies and the wall of the ring groove in the piston. The two ring elements engage with each other on their flat sides, and there is a notch for accommodating lubrication oil provided in the engaging portion. The radial cuts in each ring element stagger each other by an angle of 180.degree.. The two ring elements are good sealing and lubricating, respectively, therefore they can reduce the leakage of gas and the compensation of oil, and have a long period of use. They can thus improve the efficiency and the power of internal combustion engine, and reduce the emission and the noise of the internal combustion engine.
摘要:
An output driver that includes a pull-up network comprising a first plurality of resistive branches forming a first R-2R resistive ladder structure, wherein the resistive branches of the pull-up network are coupled to a high voltage supply through pull-up switching transistors. The output driver may further include a pull-down network comprising a second plurality of resistive branches forming a second R-2R resistive ladder structure, wherein the resistive branches of the pull-down network are coupled to a low voltage supply through pull-down switching transistors. The output driver includes a control circuit to selectively activate or deactivate each of the first plurality of resistive branches and to selectively activate or deactivate each of the second plurality of resistive branches.