摘要:
A filter includes cascaded building blocks, for filtering an incoming signal. Each building block has first and second delay elements. A first scaling device is between an input node of the first delay element and an output node of the second delay element, and a second scaling device is between an output node of the first delay element and an input node of the second delay element. The building block has a cross scaling device between the output nodes of the first delay element and of the second delay element, and/or between the input nodes of the first delay element and of the second delay element. The building block is configured such that, in operation, incoming signals at the input node and output node of the second delay element are summed together.
摘要:
High-data rate channel interface modules and equalization methods employing a finite impulse response (FIR) analog receive filter. Embodiments include an illustrative channel interface module having multiple amplifier-based delay units arranged in a sequential chain to convert an analog input signal into a set of increasingly-delayed analog signals that are weighted and combined together with the analog input signal to form an equalized signal; and a symbol decision element operating on the equalized signal to obtain a sequence of symbol decisions. An interface that extracts received data from the sequence of symbol decisions. The delay units may employ one or more delay cells each having a common-source amplifier stage followed by a source follower output stage, the two stages providing approximately equal portions of the propagation delay. An enhanced gate-to-drain capacitance in the common-source amplifier may increase propagation delay while reducing bandwidth limitations.
摘要:
A charge sharing filter includes a rotating capacitor, and a plurality of elementary filters, each elementary filter comprising: an elementary switch coupled between a first node of the respective elementary filter and a second node of the respective elementary filter; and a history capacitor coupled to the first node of the respective elementary filter, wherein the second nodes of the plurality of elementary filters are interconnected with the rotating capacitor in one interconnecting node.
摘要:
A method and system for designing and implementing a finite impulse response (FIR) filter to create a plurality of output signals, each output signal having the same frequency but at a different phase shift from the other output(s), is described. Values are determined for the resistors, or other elements having impedance values, in a FIR filter having a plurality of outputs, such that each output has the same frequency response but a different phase than the other output(s). This is accomplished by the inclusion of a phase factor in the time domain calculation of the resistor values that does not change the response in the frequency domain. The phase shift is constant and independent of the frequency of the output signal.
摘要:
An approach to time domain filtering uses a passive charge sharing approach to implement an infinite impulse response filter. Delayed samples of an input signal are stored as charges on capacitors of a first array of capacitors, and delayed samples of the output signal are stored as charges on capacitors of a second array of capacitors. Outputs are determined by passively coupling capacitors of the first and second arrays to one another, and determining the output according to a total charge on the coupled capacitors. In some examples, a gain is applied to the total charge prior to storing the output on the second array of capacitors. In some examples, a charge scaling circuit is applied to the charges stored on the arrays prior to coupling capacitors to form the output.
摘要:
A programmable signal translating device, praticularly a transversal filter, includes a wave transport body for transporting a wave along its length, a first channel of electrical conductors having a plurality of code sections spaced along its length for generating phase-coded electrical signals from the wave propagated by the transport body, a second channel of electrical conductors connected in parallel to the first channel and of identical code sections as, but of opposite polarity to, the first channel, and programmable electrical connections between the code sections of the first channel and the code sections of the second channel and the output circuit, for connecting selected code sections of the first and second channels to the output circuit.
摘要:
A data-in-voice modem is disclosed using charge coupled devices. Unique features include: (1) Baseband-to-IF upconversion to enable CCD-based demod/processing; (2) All analog (no analog-to-digital A/D required); option for post-CCD A/D; (3) Additional on-chip functions; (4) Stand-alone, CCD-based high-rate modem over telephone lines; and (5) CCD-based cable-tv/multimedia processing, via baseband-to-IF upconversion, followed by IF-sampled CCD processing.
摘要:
A high precision fast finite impulse response (FIR) filter which periodically samples an analog input signal and holds a sequentially-replaced number of the resulting discrete-time analog values in fixed storage cells while each value is being multiplied by a number of digital weights. The discrete-time analog values are not passed through delay devices and therefore do not degrade. The weights are stored in a memory or shift register and supplied to the multipliers in a repeating sequence. A predetermined number of the weights are set to zero to increase the setup time of the analog multipliers thereby increasing the precision without slowing the clocking frequency.
摘要:
In an apparatus having a CCD for compressing and/or expanding the time base of an input signal; a first two-phase transfer clock pulse signal made up of first and second pulse train signals having a first period and arranged to be 180.degree. out of phase with each other is used for driving the CCD while writing the input signal into the CCD, a second two-phase transfer clock pulse signal made up of third and fourth pulse train signals having a second period and arranged to be 180.degree. out of phase with each other is used for driving the CCD while reading from the CCD a signal which is produced from the input signal with its time base compressed or expanded, and the pulse width of the first pulse train signal is made virtually equal to the pulse width of the third pulse train signal and such pulse width is selected to be smaller than one-half of the smaller of the first and second periods.
摘要:
The invention provides a method of forming electrodes aligned with respect to an implantation level in a substrate, including the following main phases:formation of a dielectric layer on a substrate;formation of semiconducting or conducting elements which are to serve as mask for implantation;implantation;formation of a layer of conducting or semiconducting material;cutting out electrodes from said layer and from the semiconducting or conducting elements.