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Low-pass filter

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412: 2247: 549: 4348: 5950: 428: 5909: 6146: 4275: 36: 5067: 4680: 4548:—depend on the characteristics of the filter. The term "low-pass filter" merely refers to the shape of the filter's response; a high-pass filter could be built that cuts off at a lower frequency than any low-pass filter—it is their responses that set them apart. Electronic circuits can be devised for any desired frequency range, right up through microwave frequencies (above 1 GHz) and higher. 3266: 4256:
time-domain response of an ideal sharp-cutoff low-pass filter. For minimum distortion, the finite impulse response filter has an unbounded number of coefficients operating on an unbounded signal. In practice, the time-domain response must be time truncated and is often of a simplified shape; in the
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For non-realtime filtering, to achieve a low pass filter, the entire signal is usually taken as a looped signal, the Fourier transform is taken, filtered in the frequency domain, followed by an inverse Fourier transform. Only O(n log(n)) operations are required compared to O(n) for the time domain
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However, the ideal filter is impossible to realize without also having signals of infinite extent in time, and so generally needs to be approximated for real ongoing signals, because the sinc function's support region extends to all past and future times. The filter would therefore need to have
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may have different meanings, depending on whether referring to the frequency or wavelength of light, since these variables are inversely related. High-pass frequency filters would act as low-pass wavelength filters, and vice versa. For this reason, it is a good practice to refer to wavelength
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infinite delay, or knowledge of the infinite future and past, to perform the convolution. It is effectively realizable for pre-recorded digital signals by assuming extensions of zero into the past and future, or, more typically, by making the signal repetitive and using Fourier analysis.
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At high frequencies, the capacitor only has time to charge up a small amount before the input switches direction. The output goes up and down only a small fraction of the amount the input goes up and down. At double the frequency, there's only time for it to charge up half the
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reduces the signal amplitude to one-fourth of its original level every time the frequency doubles (so power decreases by 12 dB per octave, or 40 dB per decade). Other all-pole second-order filters may roll off at different rates initially depending on their
2758: 1444: 664: 5381: 467:. The transition region present in practical filters does not exist in an ideal filter. An ideal low-pass filter can be realized mathematically (theoretically) by multiplying a signal by the rectangular function in the frequency domain or, equivalently, 4459:, the Bode plot flattens out again, at some maximum attenuation of high frequencies; such an effect is caused for example by a little bit of the input leaking around the one-pole filter; this one-pole–one-zero filter is still a first-order low-pass. 1130: 277:
A stiff physical barrier tends to reflect higher sound frequencies, acting as an acoustic low-pass filter for transmitting sound. When music is playing in another room, the low notes are easily heard, while the high notes are attenuated.
4707:, and blocks low-frequency signals, forcing them through the load instead. At higher frequencies, the reactance drops, and the capacitor effectively functions as a short circuit. The combination of resistance and capacitance gives the 2646: 246:. That is a filter with unity bandwidth and impedance. The desired filter is obtained from the prototype by scaling for the desired bandwidth and impedance and transforming into the desired bandform (that is, low-pass, high-pass, 517:
involves understanding and minimizing these artifacts. For example, simple truncation of the sinc function will create severe ringing artifacts, which can be reduced using window functions that drop off more smoothly at the edges.
3799: 3261:{\displaystyle y_{i}=\overbrace {x_{i}\left({\frac {\Delta _{T}}{RC+\Delta _{T}}}\right)} ^{\text{Input contribution}}+\overbrace {y_{i-1}\left({\frac {RC}{RC+\Delta _{T}}}\right)} ^{\text{Inertia from previous output}}.} 1620: 4626: 2508: 4564:, in a way that lets all characteristics of the filter be easily analyzed by considering the pattern of poles and zeros of the Laplace transform in the complex plane. (In discrete time, one can similarly consider the 3562: 5118:
will. The main difference that the presence of the resistor makes is that any oscillation induced in the circuit will die away over time if it is not kept going by a source. This effect of the resistor is called
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attenuates high frequencies more steeply. The Bode plot for this type of filter resembles that of a first-order filter, except that it falls off more quickly. For example, a second-order
2660: 1237: 5830:- Signals are phase-shifted 180° and attenuated by the square of the frequency ratio. This behavior is detailed by Jim Karki in "Active Low-Pass Filter Design" (Texas Instruments, 2023). 3673: 3450: 569: 5639: 5142:, where they are used to select a narrow range of frequencies from the ambient radio waves. In this role, the circuit is often called a tuned circuit. An RLC circuit can be used as a 3619: 5234: 4447:, and a diagonal line above the cutoff frequency. There is also a "knee curve" at the boundary between the two, smoothly transitioning between the two straight-line regions. If the 1669: 873: 1731: 1788: 239:
techniques as are used for other low-pass filters. Low-pass filters provide a smoother form of a signal, removing the short-term fluctuations and leaving the longer-term trend.
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of an ideal low-pass filter. The ripples of a true sinc extend infinitely to the left and right while getting smaller and smaller, but this particular graph is truncated.
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There are many different types of filter circuits, with different responses to changing frequency. The frequency response of a filter is generally represented using a
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is the quality factor. Equation 1 describes three regions of operation: below cutoff, in the area of cutoff, and above cutoff. For each area, Equation 1 reduces to:
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The capacitor is not an "on/off" object (like the block or pass fluidic explanation above). The capacitor variably acts between these two extremes. It is the
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This can also sometimes be done in real time, where the signal is delayed long enough to perform the Fourier transformation on shorter, overlapping blocks.
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The effect of an infinite impulse response low-pass filter can be simulated on a computer by analyzing an RC filter's behavior in the time domain, and then
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for digital implementation of Butterworth, Bessel, and Chebyshev filters created by the late Dr. Tony Fisher of the University of York (York, England).
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The filter recurrence relation provides a way to determine the output samples in terms of the input samples and the preceding output. The following
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This equation can be discretized. For simplicity, assume that samples of the input and output are taken at evenly spaced points in time separated by
6343: 6314: 4966:(AC) flows very well through the capacitor, almost as well as it flows through a solid wire, AC input flows out through the capacitor, effectively 1502: 4577: 2079:, we find that there is an exact reconstruction (0% error). This is the reconstructed output for a time-invariant input. However, if the input is 2448: 3502: 4756: 5958: 6439: 6182: 3810: 2986: 4840: 522: 5750: 886: 743: 1998: 6260: 4904:
At low frequencies, there is plenty of time for the capacitor to charge up to practically the same voltage as the input voltage.
3402:{\displaystyle y_{i}=\alpha x_{i}+(1-\alpha )y_{i-1}\qquad {\text{where}}\qquad \alpha :={\frac {\Delta _{T}}{RC+\Delta _{T}}}.} 2273: 5094:, connected in series or in parallel. The RLC part of the name is due to those letters being the usual electrical symbols for 100: 5050: 6064: 883:
The most common way to characterize the frequency response of a circuit is to find its Laplace transform transfer function,
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for voltage signals, high frequencies in the input signal are attenuated, but the filter has little attenuation below the
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This circuit may be understood by considering the time the capacitor needs to charge or discharge through the resistor:
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On any Butterworth filter, if one extends the horizontal line to the right and the diagonal line to the upper-left (the
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in the limit of high frequency. The magnitude Bode plot for a first-order filter looks like a horizontal line below the
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increasing by a power of two, the last formula describes a second-order low-pass filter. The frequency scaling factor
3926: 6364: 6223: 4322: 2753:{\displaystyle v_{\text{in}}(t)-v_{\text{out}}(t)=RC{\frac {\operatorname {d} v_{\text{out}}}{\operatorname {d} t}}.} 1439:{\displaystyle v_{\rm {out}}(nT)-v_{\rm {out}}((n-1)T)=V_{i}(1-e^{-\omega _{0}nT})-V_{i}(1-e^{-\omega _{0}((n-1)T)})} 119: 4304: 659:{\displaystyle v_{\text{out}}(t)=v_{\text{in}}(t)-RC{\frac {\operatorname {d} v_{\text{out}}}{\operatorname {d} t}}} 6432: 4296: 2368: 340: 235:
operation used in fields such as finance is a particular kind of low-pass filter and can be analyzed with the same
53: 5376:{\displaystyle H_{LP}(f)=-{\frac {K}{f_{FSF}\cdot f_{c}^{2}+{\frac {1}{Q}}\cdot jf_{FSF}\cdot f_{c}+1}}\quad (1)} 4493:
Third- and higher-order filters are defined similarly. In general, the final rate of power rolloff for an order-
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Low-pass filters also play a significant role in the sculpting of sound created by analogue and virtual analogue
327:, to block high pitches that they cannot efficiently reproduce. Radio transmitters use low-pass filters to block 141: 86: 5591: 5020:. A first-order RL circuit is composed of one resistor and one inductor and is the simplest type of RL circuit. 4423:
of the filter determines the amount of additional attenuation for frequencies higher than the cutoff frequency.
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The time response of a low-pass filter is found by solving the response to the simple low-pass RC filter.
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is used to scale the cutoff frequency of the filter so that it follows the definitions given before.
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drops off at −6 dB per octave (that is −20 dB per decade) as it is a first-order filter.
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with the same function can correctly be called a low-pass filter, but conventionally is called a
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circuit, meaning that any voltage or current in the circuit can be described by a second-order
4696: 1170: 1125:{\displaystyle H(s)={V_{\rm {out}}(s) \over V_{\rm {in}}(s)}={\omega _{0} \over s+\omega _{0}}} 514: 6239: 5905:
Higher-order passive filters can also be constructed (see diagram for a third-order example).
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is the time between samples. Taking the difference between two consecutive samples we have
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There are many applications for this circuit. They are used in many different types of
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Low-pass filters exist in many different forms, including electronic circuits such as a
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is easily obtained by sampling the step input response above at regular intervals of
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For example, a first-order low-pass filter can be described in Laplace notation as:
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algorithm simulates the effect of a low-pass filter on a series of digital samples:
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The gain-magnitude frequency response of a first-order (one-pole) low-pass filter.
420: 359: 301: 297: 251: 247: 243: 173: 149: 6375: 6469: 4746:). The break frequency, also called the turnover frequency, corner frequency, or 4258: 2240: 491: 332: 309: 212: 3794:{\displaystyle \alpha ={\frac {2\pi \Delta _{T}f_{c}}{2\pi \Delta _{T}f_{c}+1}}} 331:
emissions that might interfere with other communications. The tone knob on many
6534: 5913: 5139: 5046: 5017: 5013: 4924:(DC) cannot flow through the capacitor, DC input must flow out the path marked 4921: 2980:, which correspond to the same points in time. Making these substitutions, 2216: 2170:
producing an error in the reconstructed output signal. The error produced from
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of a second-order low-pass filter can be expressed as a function of frequency
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Plot of the gain of Butterworth low-pass filters of orders 1 through 5, with
4253: 4072: 3457: 1615:{\displaystyle v_{\rm {out}}(nT)=\beta v_{\rm {out}}((n-1)T)+(1-\beta )V_{i}} 499: 476: 416: 411: 228: 161: 6417: 4621:{\displaystyle {\frac {\text{Output}}{\text{Input}}}=K{\frac {1}{\tau s+1}}} 4347: 974:. Taking the Laplace transform of our differential equation and solving for 304:. For current signals, a similar circuit, using a resistor and capacitor in 5949: 2503:{\displaystyle i(t)={\frac {\operatorname {d} Q_{c}}{\operatorname {d} t}}} 363: 347: 6398:, a short primer on the mathematical analysis of (electrical) LTI systems. 6298: 335:
is a low-pass filter used to reduce the amount of treble in the sound. An
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as shown in Equation 1, the Second-Order Low-Pass Filter Standard Form.
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For another method of conversion from continuous- to discrete-time, see
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Comparing the reconstructed output signal from the difference equation,
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to the difference between the previous output and the next input. This
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to the ground (analogous to replacing the capacitor with just a wire).
4517:, 3 dB below the horizontal line. The various types of filters ( 5908: 5111: 5091: 4997: 4975: 4700: 4510: 4416: 4400: 3873:{\displaystyle f_{c}={\frac {\alpha }{(1-\alpha )2\pi \Delta _{T}}}.} 3074:{\displaystyle x_{i}-y_{i}=RC\,{\frac {y_{i}-y_{i-1}}{\Delta _{T}}}.} 1135: 320: 293: 263: 156:
signals with frequencies higher than the cutoff frequency. The exact
153: 145: 4274: 35: 6327: 6159: 6145: 6131: 5692:- Signals are phase-shifted 90° and modified by the quality factor 5087: 5083: 5038: 5034: 5009: 5005: 4890:{\displaystyle \omega _{\mathrm {c} }={1 \over \tau }={1 \over RC}} 4692: 4652: 4483: 4408: 328: 4252:
Finite-impulse-response filters can be built that approximate the
5823:{\displaystyle H_{LP}(f)\approx -{\frac {K}{f_{FSF}\cdot f^{2}}}} 5120: 4912:
Another way to understand this circuit is through the concept of
4236: 436: 6303:. New York: McGRAW-HILL BOOK COMPANY. pp. 211–224, 684–729. 525:
describes how to use a perfect low-pass filter to reconstruct a
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in audio applications. A low-pass filter is the complement of a
5078:(the letters R, L, and C can be in a different sequence) is an 5066: 4831: 4439:); more precisely, the power rolloff approaches 20 dB per 4436: 443:
is shown on a logarithmic scale in units of radians per second.
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filter (low frequency is long wavelength), to avoid confusion.
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operational amplifier applications § Inverting integrator
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Continuous-time filters can also be described in terms of the
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decay seen in the continuous-time system. As expected, as the
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Elementary Differential Equations and Boundary Value Problems
5991: 5165: 4679: 967:{\displaystyle H(s)={V_{\rm {out}}(s) \over V_{\rm {in}}(s)}} 820:{\displaystyle v_{\text{out}}(t)=V_{i}(1-e^{-\omega _{0}t}),} 2072:{\displaystyle v_{\text{out}}(t)=V_{i}(1-e^{-\omega _{0}t})} 490:
applications approximate the ideal filter by truncating and
5566:- The circuit passes signals multiplied by the gain factor 4059:
That is, the change from one filter output to the next is
2340:{\displaystyle v_{\text{in}}(t)-v_{\text{out}}(t)=R\;i(t)} 2234: 6358:
Signal recovery from noise in electronic instrumentation.
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Active Low-Pass Filter Design" (Texas Instruments, 2023)
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is significantly larger than the sampling interval, and
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decline reflects an additional half-power attenuation).
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That is, this discrete-time implementation of a simple
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Filter designers will often use the low-pass form as a
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circuit shown in the figure, the cutoff frequency (in
6067: 6048:{\displaystyle f_{\text{c}}={\frac {1}{2\pi R_{2}C}}} 6003: 5870: 5843: 5753: 5720: 5698: 5647: 5594: 5572: 5527: 5494: 5471: 5438: 5411: 5391: 5237: 5215: 5176: 4930: 4843: 4759: 4717: 4580: 4360: 4172: 4166:
respond more slowly to a change in the input samples
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Long Pass Filters and Short Pass Filters Information
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From the circuit diagram to the right, according to
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are designed to give low-pass characteristics. Both
2143:{\displaystyle v_{\text{in}}(t)=V_{i}\sin(\omega t)} 6299:Hayt, William H. Jr. and Kemmerly, Jack E. (1978). 1988:{\displaystyle V_{n}=\beta V_{n-1}+(1-\beta )v_{n}} 1903:{\displaystyle V_{n}=\beta V_{n-1}+(1-\beta )v_{n}} 60:. Unsourced material may be challenged and removed. 6332:. New York: JOHN WILEY & SONS. pp. 11–24. 6207: 6105: 6047: 5889: 5856: 5822: 5739: 5704: 5684: 5633: 5578: 5558: 5513: 5477: 5457: 5424: 5397: 5375: 5221: 5201: 4951: 4889: 4819: 4734: 4703:in parallel with the load. The capacitor exhibits 4620: 4379: 4226: 4158: 4090: 3956: 3911: 3872: 3793: 3701: 3667: 3613: 3556: 3484: 3444: 3401: 3260: 3073: 2972: 2904: 2877: 2809: 2782: 2752: 2640: 2554: 2502: 2419: 2339: 2192: 2162: 2142: 2071: 1987: 1902: 1822: 1782: 1725: 1663: 1614: 1488: 1438: 1223: 1203: 1159: 1136:Difference equation through discrete time sampling 1124: 995: 966: 867: 819: 729: 702: 658: 319:Electronic low-pass filters are used on inputs to 4227:{\displaystyle (x_{1},\,x_{2},\,\ldots ,\,x_{n})} 4159:{\displaystyle (y_{1},\,y_{2},\,\ldots ,\,y_{n})} 4078:increases, the discrete-time smoothing parameter 4011:α := dt / (RC + dt) y := α * x 2973:{\displaystyle (y_{1},\,y_{2},\,\ldots ,\,y_{n})} 2878:{\displaystyle (x_{1},\,x_{2},\,\ldots ,\,x_{n})} 2174:inputs is difficult to quantify but decreases as 6501: 6177: 6175: 5944: 5916:). The filter becomes a Butterworth filter with 5023:A first-order RL circuit is one of the simplest 4750:(in hertz), is determined by the time constant: 4513:of the function), they intersect at exactly the 4435:, every time the frequency doubles (goes up one 3957:{\displaystyle \Delta _{T}\;\approx \;\alpha RC} 737:then the differential equation has the solution 451:completely eliminates all frequencies above the 313: 5900: 4533:. Many second-order filters have "peaking" or 2562:is the charge stored in the capacitor at time 227:for smoothing sets of data, acoustic barriers, 4658: 4544:The meanings of 'low' and 'high'—that is, the 4342: 669: 505:Truncating an ideal low-pass filter result in 196:to avoid confusion, which would correspond to 6447: 6433: 6172: 4419:the input power by half or 3 dB. So the 3891:time constant equals the sampling period. If 2420:{\displaystyle Q_{c}(t)=C\,v_{\text{out}}(t)} 6342:: CS1 maint: multiple names: authors list ( 6328:Boyce, William and DiPrima, Richard (1965). 6313:: CS1 maint: multiple names: authors list ( 4261:can be used, giving a square time response. 2203: 6285:Mastering Windows: Improving Reconstruction 4303:. Unsourced material may be challenged and 3668:{\displaystyle RC={\frac {1}{2\pi f_{c}}},} 3445:{\displaystyle 0\;\leq \;\alpha \;\leq \;1} 2227:low pass filters, as well as filters using 6440: 6426: 6396:ECE 209: Review of Circuits as LTI Systems 6263:. Pcweenie.com. 2009-04-12. Archived from 6202: 5634:{\displaystyle {\frac {f}{f_{c}}}=f_{FSF}} 5166:Second-Order Low-Pass Filter Standard Form 4725: 4721: 4247: 4023:n y := α * x + (1-α) * y 3944: 3940: 3905: 3901: 3614:{\displaystyle f_{c}={\frac {1}{2\pi RC}}} 3438: 3434: 3430: 3426: 2601: 2597: 2324: 6058:or equivalently (in radians per second): 4403:, and the filter is characterized by its 4323:Learn how and when to remove this message 4210: 4203: 4189: 4142: 4135: 4121: 3022: 2956: 2949: 2935: 2861: 2854: 2840: 2648:, which can be substituted into equation 2397: 455:while passing those below unchanged; its 406: 120:Learn how and when to remove this message 5948: 5907: 5130:. Another important application is for 5065: 4678: 4346: 2245: 1664:{\displaystyle \beta =e^{-\omega _{0}T}} 868:{\displaystyle \omega _{0}={1 \over RC}} 547: 494:the infinite impulse response to make a 426: 410: 6214:. Saunders College Publishing. p.  4683:Passive, first order low-pass RC filter 4451:of a first-order low-pass filter has a 2235:Simple infinite impulse response filter 1726:{\displaystyle V_{n}=v_{\rm {out}}(nT)} 875:is the cutoff frequency of the filter. 563:we arrive at the differential equation 523:Whittaker–Shannon interpolation formula 14: 6502: 6261:"Home Networking – Local Area Network" 5837:With attenuation at frequencies above 4959:(analogous to removing the capacitor). 1790:, and substituting our sampled value, 1783:{\displaystyle v_{n}=v_{\rm {in}}(nT)} 262:Examples of low-pass filters occur in 6421: 5465:is the frequency scaling factor, and 5106:, respectively. The circuit forms a 3277:exponentially weighted moving average 878: 6294: 6292: 4301:adding citations to reliable sources 4268: 4264: 4056:n y := y + α * (x - y) 2442: 2362: 2267: 58:adding citations to reliable sources 29: 6408:by means of trigonometric identity. 5154:. The RLC filter is described as a 4635:is the Laplace transform variable, 4551: 4537:that puts their frequency response 4529:, etc.) all have different-looking 4244:(IIR) single-pole low-pass filter. 308:, works in a similar manner. (See 164:. The filter is sometimes called a 24: 5559:{\displaystyle H_{LP}(f)\approx K} 4952:{\displaystyle V_{\mathrm {out} }} 4943: 4940: 4937: 4850: 4766: 4541:the horizontal line at this peak. 4098:decreases, and the output samples 3931: 3912:{\displaystyle \alpha \;\ll \;0.5} 3855: 3763: 3735: 3516: 3473: 3384: 3364: 3227: 3151: 3131: 3057: 2771: 2735: 2717: 2626: 2608: 2488: 2470: 1762: 1759: 1705: 1702: 1699: 1554: 1551: 1548: 1518: 1515: 1512: 1468: 1465: 1462: 1286: 1283: 1280: 1253: 1250: 1247: 1069: 1066: 1043: 1040: 1037: 946: 943: 920: 917: 914: 644: 626: 362:vice versa), which share the same 25: 6546: 6384: 6289: 4742:(represented by the Greek letter 1913: 1830:, we get the difference equation 1489:{\displaystyle v_{\rm {out}}(nT)} 537:uses real filter approximations. 515:Design and choice of real filters 350:use low-pass filters to separate 6144: 5070:RLC circuit as a low-pass filter 4992:RL circuit § Series circuit 4675:RC circuit § Series circuit 4273: 3465:in terms of the sampling period 710:be a step function of magnitude 703:{\displaystyle v_{\text{in}}(t)} 540: 435:is shown in decibels (i.e., a 3 387:A low-pass filter is used as an 219:for conditioning signals before 34: 6402:ECE 209: Sources of Phase Shift 5912:A third-order low-pass filter ( 5363: 5056: 4996:A resistor–inductor circuit or 3354: 3348: 2912:be represented by the sequence 2817:be represented by the sequence 45:needs additional citations for 6391:Low Pass Filter java simulator 6369: 6350: 6321: 6278: 6253: 6232: 6210:Microelectronic Circuits, 3 ed 6196: 5773: 5767: 5667: 5661: 5547: 5541: 5370: 5364: 5257: 5251: 5196: 5190: 4663: 4221: 4173: 4153: 4105: 3845: 3833: 3329: 3317: 2967: 2919: 2905:{\displaystyle v_{\text{out}}} 2872: 2824: 2702: 2696: 2680: 2674: 2594: 2588: 2549: 2543: 2461: 2455: 2414: 2408: 2388: 2382: 2334: 2328: 2315: 2309: 2293: 2287: 2193:{\displaystyle T\rightarrow 0} 2184: 2137: 2128: 2106: 2100: 2066: 2034: 2018: 2012: 1995:, to the step input response, 1972: 1960: 1887: 1875: 1777: 1768: 1720: 1711: 1599: 1587: 1581: 1575: 1563: 1560: 1533: 1524: 1483: 1474: 1433: 1428: 1422: 1410: 1407: 1380: 1364: 1329: 1313: 1307: 1295: 1292: 1268: 1259: 1081: 1075: 1055: 1049: 1022: 1016: 990: 984: 958: 952: 932: 926: 899: 893: 811: 779: 763: 757: 697: 691: 611: 605: 589: 583: 13: 1: 6165: 6116:The gain in the passband is − 5945:Active electronic realization 5685:{\displaystyle H_{LP}(f)=jKQ} 5061: 4380:{\displaystyle \omega _{0}=1} 2810:{\displaystyle v_{\text{in}}} 160:of the filter depends on the 6301:Engineering Circuit Analysis 6206:; Smith, Kenneth C. (1991). 5901:Higher order passive filters 5053:driven by a current source. 4985: 4982:that show this variability. 4735:{\displaystyle \tau \;=\;RC} 4668: 4034:that calculates each of the 3251:Inertia from previous output 3084:Rearranging terms gives the 535:digital-to-analog converters 401:digital-to-analog conversion 346:Telephone lines fitted with 221:analog-to-digital conversion 7: 6137: 5405:is the frequency variable, 4916:at a particular frequency: 4687:One simple low-pass filter 4659:Electronic low-pass filters 4387:. Note that the slope is 20 4343:Continuous-time realization 3485:{\displaystyle \Delta _{T}} 2783:{\displaystyle \Delta _{T}} 2650: 2574: 2568: 2516: 2433: 2353: 1823:{\displaystyle v_{n}=V_{i}} 670:Step input response example 257: 10: 6551: 5956: 5740:{\displaystyle f\gg f_{c}} 5514:{\displaystyle f\ll f_{c}} 4989: 4672: 4568:of the impulse response.) 2207: 292:In an electronic low-pass 231:of images, and so on. The 6525:Filter frequency response 6488: 6455: 6449:Signal-processing filters 5953:An active low-pass filter 5432:is the cutoff frequency, 5202:{\displaystyle H_{LP}(f)} 5028:infinite impulse response 4242:infinite-impulse-response 2790:time. Let the samples of 2221:infinite impulse response 2204:Discrete-time realization 1204:{\displaystyle n=0,1,...} 312:discussed in more detail 6356:Whilmshurst, T H (1990) 6240:"ADSL filters explained" 5971:low-pass filter adds an 2566:. Substituting equation 2555:{\displaystyle Q_{c}(t)} 5924:=1 when (for example) C 5890:{\displaystyle f_{FSF}} 5458:{\displaystyle f_{FSF}} 5114:in a similar way as an 4411:. In all cases, at the 4248:Finite impulse response 4091:{\displaystyle \alpha } 3452:. The expression for 3275:low-pass filter is the 2225:finite impulse response 496:finite impulse response 6465:High-pass filter (HPF) 6107: 6049: 5954: 5941: 5891: 5858: 5824: 5741: 5706: 5686: 5635: 5580: 5560: 5515: 5479: 5459: 5426: 5399: 5377: 5223: 5203: 5170:The transfer function 5150:, low-pass filter, or 5071: 4953: 4891: 4821: 4736: 4684: 4622: 4407:and rate of frequency 4396: 4381: 4234:; the system has more 4228: 4160: 4092: 3958: 3913: 3874: 3795: 3703: 3669: 3615: 3558: 3492:and smoothing factor 3486: 3456:yields the equivalent 3446: 3403: 3262: 3075: 2974: 2906: 2879: 2811: 2784: 2754: 2642: 2556: 2504: 2421: 2341: 2261:and the definition of 2254: 2194: 2164: 2144: 2073: 1989: 1904: 1824: 1784: 1727: 1665: 1616: 1490: 1440: 1225: 1205: 1161: 1126: 997: 968: 869: 821: 731: 704: 660: 556: 479:, in the time domain. 444: 424: 407:Ideal and real filters 148:lower than a selected 6460:Low-pass filter (LPF) 6108: 6050: 5988:operational amplifier 5952: 5911: 5892: 5859: 5857:{\displaystyle f_{c}} 5825: 5742: 5707: 5687: 5636: 5581: 5561: 5516: 5480: 5460: 5427: 5425:{\displaystyle f_{c}} 5400: 5378: 5224: 5204: 5162:in circuit analysis. 5160:differential equation 5110:for current and will 5069: 4954: 4892: 4822: 4737: 4682: 4651:of the filter in the 4623: 4382: 4350: 4336:filtering algorithm. 4240:. This filter is an 4229: 4161: 4093: 4067:property matches the 4065:exponential smoothing 4042:into the equivalent: 3959: 3914: 3875: 3796: 3704: 3702:{\displaystyle f_{c}} 3670: 3616: 3559: 3487: 3447: 3404: 3263: 3076: 2975: 2907: 2880: 2812: 2785: 2755: 2643: 2557: 2505: 2422: 2342: 2249: 2195: 2165: 2145: 2074: 1990: 1905: 1825: 1785: 1728: 1666: 1617: 1491: 1441: 1226: 1206: 1162: 1127: 998: 969: 870: 822: 732: 730:{\displaystyle V_{i}} 705: 661: 551: 449:ideal low-pass filter 430: 414: 381:subtractive synthesis 217:anti-aliasing filters 27:Type of signal filter 6065: 6001: 5868: 5841: 5751: 5718: 5696: 5645: 5592: 5570: 5525: 5492: 5469: 5436: 5409: 5389: 5235: 5213: 5174: 4928: 4841: 4830:or equivalently (in 4757: 4715: 4578: 4497:all-pole filter is 6 4395:is the filter order. 4358: 4297:improve this section 4170: 4102: 4082: 3978:, and time constant 3927: 3895: 3811: 3716: 3686: 3625: 3574: 3503: 3469: 3420: 3416:is within the range 3285: 3094: 2987: 2916: 2889: 2821: 2794: 2767: 2661: 2582: 2530: 2449: 2369: 2274: 2178: 2154: 2087: 1999: 1922: 1837: 1794: 1737: 1677: 1629: 1503: 1453: 1238: 1215: 1171: 1148: 1010: 996:{\displaystyle H(s)} 978: 887: 834: 744: 714: 678: 570: 461:rectangular function 389:anti-aliasing filter 368:transmission channel 54:improve this article 6520:Synthesiser modules 5305: 5128:oscillator circuits 5108:harmonic oscillator 5033:. It consists of a 4964:alternating current 4475:second-order filter 3412:By definition, the 3086:recurrence relation 2231:, are widely used. 1673:Using the notation 1142:difference equation 323:and other types of 6152:Electronics portal 6103: 6045: 5955: 5942: 5887: 5854: 5820: 5737: 5702: 5682: 5631: 5576: 5556: 5511: 5475: 5455: 5422: 5395: 5385:In this equation, 5373: 5291: 5219: 5199: 5080:electrical circuit 5072: 5031:electronic filters 4980:frequency response 4949: 4887: 4817: 4732: 4685: 4618: 4519:Butterworth filter 4479:Butterworth filter 4429:first-order filter 4397: 4377: 4224: 4156: 4088: 3954: 3909: 3870: 3791: 3699: 3665: 3611: 3554: 3482: 3442: 3399: 3258: 3175:Input contribution 3071: 2970: 2902: 2875: 2807: 2780: 2750: 2638: 2552: 2500: 2417: 2337: 2255: 2250:A simple low-pass 2229:Fourier transforms 2210:Bilinear transform 2190: 2160: 2140: 2069: 1985: 1900: 1820: 1780: 1723: 1661: 1612: 1486: 1436: 1221: 1201: 1160:{\displaystyle nT} 1157: 1122: 993: 964: 879:Frequency response 865: 817: 727: 700: 656: 557: 552:A simple low-pass 457:frequency response 445: 425: 419:, the time-domain 300:determined by its 158:frequency response 6510:Signal processing 6497: 6496: 6491:Electronic filter 6406:transfer function 6101: 6075: 6043: 6011: 5994:) is defined as: 5983:in the passband. 5963:Op amp integrator 5818: 5705:{\displaystyle Q} 5610: 5579:{\displaystyle K} 5478:{\displaystyle Q} 5398:{\displaystyle f} 5361: 5317: 5222:{\displaystyle f} 4885: 4867: 4815: 4791: 4695:in series with a 4616: 4589: 4588: 4585: 4558:Laplace transform 4501:dB per octave (20 4449:transfer function 4413:cutoff frequency, 4333: 4332: 4325: 4265:Fourier transform 4257:simplest case, a 3887:=0.5, then the 3865: 3789: 3660: 3609: 3545: 3394: 3352: 3254: 3252: 3247: 3237: 3178: 3176: 3171: 3161: 3066: 2899: 2804: 2745: 2730: 2693: 2671: 2636: 2621: 2524: 2523: 2498: 2441: 2440: 2405: 2361: 2360: 2306: 2284: 2163:{\displaystyle T} 2097: 2009: 1224:{\displaystyle T} 1120: 1085: 962: 863: 754: 688: 654: 639: 602: 580: 527:continuous signal 507:ringing artifacts 486:Real filters for 465:brick-wall filter 441:Angular frequency 343:low-pass filter. 237:signal processing 170:treble-cut filter 130: 129: 122: 104: 69:"Low-pass filter" 16:(Redirected from 6542: 6480:Band-stop filter 6475:Band-pass filter 6442: 6435: 6428: 6419: 6418: 6412:C code generator 6378: 6373: 6367: 6354: 6348: 6347: 6341: 6333: 6325: 6319: 6318: 6312: 6304: 6296: 6287: 6282: 6276: 6275: 6273: 6272: 6257: 6251: 6250: 6248: 6247: 6236: 6230: 6229: 6213: 6200: 6194: 6193: 6192: 6191: 6179: 6154: 6149: 6148: 6112: 6110: 6109: 6104: 6102: 6100: 6096: 6095: 6082: 6077: 6076: 6073: 6054: 6052: 6051: 6046: 6044: 6042: 6038: 6037: 6018: 6013: 6012: 6009: 5979:that allows for 5936:=3/2 henry and L 5918:cutoff frequency 5896: 5894: 5893: 5888: 5886: 5885: 5863: 5861: 5860: 5855: 5853: 5852: 5829: 5827: 5826: 5821: 5819: 5817: 5816: 5815: 5803: 5802: 5783: 5766: 5765: 5746: 5744: 5743: 5738: 5736: 5735: 5711: 5709: 5708: 5703: 5691: 5689: 5688: 5683: 5660: 5659: 5640: 5638: 5637: 5632: 5630: 5629: 5611: 5609: 5608: 5596: 5585: 5583: 5582: 5577: 5565: 5563: 5562: 5557: 5540: 5539: 5520: 5518: 5517: 5512: 5510: 5509: 5484: 5482: 5481: 5476: 5464: 5462: 5461: 5456: 5454: 5453: 5431: 5429: 5428: 5423: 5421: 5420: 5404: 5402: 5401: 5396: 5382: 5380: 5379: 5374: 5362: 5360: 5353: 5352: 5340: 5339: 5318: 5310: 5304: 5299: 5287: 5286: 5267: 5250: 5249: 5228: 5226: 5225: 5220: 5208: 5206: 5205: 5200: 5189: 5188: 5152:high-pass filter 5148:band-stop filter 5144:band-pass filter 5082:consisting of a 5002:electric circuit 4968:short circuiting 4958: 4956: 4955: 4950: 4948: 4947: 4946: 4896: 4894: 4893: 4888: 4886: 4884: 4873: 4868: 4860: 4855: 4854: 4853: 4826: 4824: 4823: 4818: 4816: 4814: 4797: 4792: 4790: 4776: 4771: 4770: 4769: 4748:cutoff frequency 4741: 4739: 4738: 4733: 4627: 4625: 4624: 4619: 4617: 4615: 4598: 4590: 4586: 4583: 4582: 4562:impulse response 4552:Laplace notation 4546:cutoff frequency 4523:Chebyshev filter 4515:cutoff frequency 4504: 4500: 4496: 4445:cutoff frequency 4434: 4405:cutoff frequency 4391:dB/decade where 4386: 4384: 4383: 4378: 4370: 4369: 4353:cutoff frequency 4328: 4321: 4317: 4314: 4308: 4277: 4269: 4233: 4231: 4230: 4225: 4220: 4219: 4199: 4198: 4185: 4184: 4165: 4163: 4162: 4157: 4152: 4151: 4131: 4130: 4117: 4116: 4097: 4095: 4094: 4089: 3963: 3961: 3960: 3955: 3939: 3938: 3918: 3916: 3915: 3910: 3886: 3879: 3877: 3876: 3871: 3866: 3864: 3863: 3862: 3828: 3823: 3822: 3800: 3798: 3797: 3792: 3790: 3788: 3781: 3780: 3771: 3770: 3754: 3753: 3752: 3743: 3742: 3726: 3709:are related by, 3708: 3706: 3705: 3700: 3698: 3697: 3681: 3674: 3672: 3671: 3666: 3661: 3659: 3658: 3657: 3638: 3620: 3618: 3617: 3612: 3610: 3608: 3591: 3586: 3585: 3563: 3561: 3560: 3555: 3550: 3546: 3541: 3530: 3524: 3523: 3495: 3491: 3489: 3488: 3483: 3481: 3480: 3464: 3455: 3451: 3449: 3448: 3443: 3414:smoothing factor 3408: 3406: 3405: 3400: 3395: 3393: 3392: 3391: 3372: 3371: 3362: 3353: 3350: 3347: 3346: 3313: 3312: 3297: 3296: 3267: 3265: 3264: 3259: 3253: 3250: 3248: 3243: 3242: 3238: 3236: 3235: 3234: 3215: 3207: 3201: 3200: 3184: 3182: 3177: 3174: 3172: 3167: 3166: 3162: 3160: 3159: 3158: 3139: 3138: 3129: 3123: 3122: 3112: 3110: 3106: 3105: 3080: 3078: 3077: 3072: 3067: 3065: 3064: 3055: 3054: 3053: 3035: 3034: 3024: 3012: 3011: 2999: 2998: 2979: 2977: 2976: 2971: 2966: 2965: 2945: 2944: 2931: 2930: 2911: 2909: 2908: 2903: 2901: 2900: 2897: 2884: 2882: 2881: 2876: 2871: 2870: 2850: 2849: 2836: 2835: 2816: 2814: 2813: 2808: 2806: 2805: 2802: 2789: 2787: 2786: 2781: 2779: 2778: 2759: 2757: 2756: 2751: 2746: 2744: 2733: 2732: 2731: 2728: 2715: 2695: 2694: 2691: 2673: 2672: 2669: 2647: 2645: 2644: 2639: 2637: 2635: 2624: 2623: 2622: 2619: 2606: 2565: 2561: 2559: 2558: 2553: 2542: 2541: 2518: 2509: 2507: 2506: 2501: 2499: 2497: 2486: 2485: 2484: 2468: 2443: 2435: 2426: 2424: 2423: 2418: 2407: 2406: 2403: 2381: 2380: 2363: 2355: 2346: 2344: 2343: 2338: 2308: 2307: 2304: 2286: 2285: 2282: 2268: 2259:Kirchhoff's Laws 2199: 2197: 2196: 2191: 2169: 2167: 2166: 2161: 2149: 2147: 2146: 2141: 2121: 2120: 2099: 2098: 2095: 2078: 2076: 2075: 2070: 2065: 2064: 2060: 2059: 2033: 2032: 2011: 2010: 2007: 1994: 1992: 1991: 1986: 1984: 1983: 1956: 1955: 1934: 1933: 1909: 1907: 1906: 1901: 1899: 1898: 1871: 1870: 1849: 1848: 1829: 1827: 1826: 1821: 1819: 1818: 1806: 1805: 1789: 1787: 1786: 1781: 1767: 1766: 1765: 1749: 1748: 1732: 1730: 1729: 1724: 1710: 1709: 1708: 1689: 1688: 1670: 1668: 1667: 1662: 1660: 1659: 1655: 1654: 1621: 1619: 1618: 1613: 1611: 1610: 1559: 1558: 1557: 1523: 1522: 1521: 1495: 1493: 1492: 1487: 1473: 1472: 1471: 1445: 1443: 1442: 1437: 1432: 1431: 1406: 1405: 1379: 1378: 1363: 1362: 1355: 1354: 1328: 1327: 1291: 1290: 1289: 1258: 1257: 1256: 1230: 1228: 1227: 1222: 1210: 1208: 1207: 1202: 1166: 1164: 1163: 1158: 1131: 1129: 1128: 1123: 1121: 1119: 1118: 1117: 1101: 1100: 1091: 1086: 1084: 1074: 1073: 1072: 1058: 1048: 1047: 1046: 1029: 1002: 1000: 999: 994: 973: 971: 970: 965: 963: 961: 951: 950: 949: 935: 925: 924: 923: 906: 874: 872: 871: 866: 864: 862: 851: 846: 845: 826: 824: 823: 818: 810: 809: 805: 804: 778: 777: 756: 755: 752: 736: 734: 733: 728: 726: 725: 709: 707: 706: 701: 690: 689: 686: 665: 663: 662: 657: 655: 653: 642: 641: 640: 637: 624: 604: 603: 600: 582: 581: 578: 561:Kirchhoff's Laws 511:Gibbs phenomenon 473:impulse response 453:cutoff frequency 421:impulse response 333:electric guitars 302:RC time constant 298:cutoff frequency 244:prototype filter 174:high-pass filter 150:cutoff frequency 125: 118: 114: 111: 105: 103: 62: 38: 30: 21: 6550: 6549: 6545: 6544: 6543: 6541: 6540: 6539: 6500: 6499: 6498: 6493: 6484: 6470:All-pass filter 6451: 6446: 6387: 6382: 6381: 6374: 6370: 6355: 6351: 6335: 6334: 6326: 6322: 6306: 6305: 6297: 6290: 6283: 6279: 6270: 6268: 6259: 6258: 6254: 6245: 6243: 6242:. Epanorama.net 6238: 6237: 6233: 6226: 6201: 6197: 6189: 6187: 6181: 6180: 6173: 6168: 6150: 6143: 6140: 6129: 6122: 6091: 6087: 6086: 6081: 6072: 6068: 6066: 6063: 6062: 6033: 6029: 6022: 6017: 6008: 6004: 6002: 5999: 5998: 5965: 5947: 5939: 5935: 5931: 5927: 5923: 5903: 5875: 5871: 5869: 5866: 5865: 5848: 5844: 5842: 5839: 5838: 5834: 5811: 5807: 5792: 5788: 5787: 5782: 5758: 5754: 5752: 5749: 5748: 5731: 5727: 5719: 5716: 5715: 5697: 5694: 5693: 5652: 5648: 5646: 5643: 5642: 5619: 5615: 5604: 5600: 5595: 5593: 5590: 5589: 5571: 5568: 5567: 5532: 5528: 5526: 5523: 5522: 5505: 5501: 5493: 5490: 5489: 5470: 5467: 5466: 5443: 5439: 5437: 5434: 5433: 5416: 5412: 5410: 5407: 5406: 5390: 5387: 5386: 5348: 5344: 5329: 5325: 5309: 5300: 5295: 5276: 5272: 5271: 5266: 5242: 5238: 5236: 5233: 5232: 5214: 5211: 5210: 5181: 5177: 5175: 5172: 5171: 5168: 5140:television sets 5136:radio receivers 5064: 5059: 4994: 4988: 4936: 4935: 4931: 4929: 4926: 4925: 4877: 4872: 4859: 4849: 4848: 4844: 4842: 4839: 4838: 4801: 4796: 4780: 4775: 4765: 4764: 4760: 4758: 4755: 4754: 4716: 4713: 4712: 4677: 4671: 4666: 4661: 4602: 4597: 4581: 4579: 4576: 4575: 4554: 4505:dB per decade). 4502: 4498: 4494: 4432: 4365: 4361: 4359: 4356: 4355: 4345: 4329: 4318: 4312: 4309: 4294: 4278: 4267: 4259:running average 4250: 4215: 4211: 4194: 4190: 4180: 4176: 4171: 4168: 4167: 4147: 4143: 4126: 4122: 4112: 4108: 4103: 4100: 4099: 4083: 4080: 4079: 4057: 4038:outputs can be 4028: 3934: 3930: 3928: 3925: 3924: 3896: 3893: 3892: 3884: 3858: 3854: 3832: 3827: 3818: 3814: 3812: 3809: 3808: 3776: 3772: 3766: 3762: 3755: 3748: 3744: 3738: 3734: 3727: 3725: 3717: 3714: 3713: 3693: 3689: 3687: 3684: 3683: 3679: 3653: 3649: 3642: 3637: 3626: 3623: 3622: 3595: 3590: 3581: 3577: 3575: 3572: 3571: 3567:Recalling that 3531: 3529: 3525: 3519: 3515: 3504: 3501: 3500: 3493: 3476: 3472: 3470: 3467: 3466: 3460: 3453: 3421: 3418: 3417: 3387: 3383: 3373: 3367: 3363: 3361: 3349: 3336: 3332: 3308: 3304: 3292: 3288: 3286: 3283: 3282: 3249: 3230: 3226: 3216: 3208: 3206: 3202: 3190: 3186: 3185: 3183: 3173: 3154: 3150: 3140: 3134: 3130: 3128: 3124: 3118: 3114: 3113: 3111: 3101: 3097: 3095: 3092: 3091: 3060: 3056: 3043: 3039: 3030: 3026: 3025: 3023: 3007: 3003: 2994: 2990: 2988: 2985: 2984: 2961: 2957: 2940: 2936: 2926: 2922: 2917: 2914: 2913: 2896: 2892: 2890: 2887: 2886: 2866: 2862: 2845: 2841: 2831: 2827: 2822: 2819: 2818: 2801: 2797: 2795: 2792: 2791: 2774: 2770: 2768: 2765: 2764: 2734: 2727: 2723: 2716: 2714: 2690: 2686: 2668: 2664: 2662: 2659: 2658: 2625: 2618: 2614: 2607: 2605: 2583: 2580: 2579: 2563: 2537: 2533: 2531: 2528: 2527: 2487: 2480: 2476: 2469: 2467: 2450: 2447: 2446: 2402: 2398: 2376: 2372: 2370: 2367: 2366: 2303: 2299: 2281: 2277: 2275: 2272: 2271: 2237: 2217:digital filters 2213: 2206: 2179: 2176: 2175: 2155: 2152: 2151: 2116: 2112: 2094: 2090: 2088: 2085: 2084: 2055: 2051: 2047: 2043: 2028: 2024: 2006: 2002: 2000: 1997: 1996: 1979: 1975: 1945: 1941: 1929: 1925: 1923: 1920: 1919: 1916: 1894: 1890: 1860: 1856: 1844: 1840: 1838: 1835: 1834: 1814: 1810: 1801: 1797: 1795: 1792: 1791: 1758: 1757: 1753: 1744: 1740: 1738: 1735: 1734: 1698: 1697: 1693: 1684: 1680: 1678: 1675: 1674: 1650: 1646: 1642: 1638: 1630: 1627: 1626: 1606: 1602: 1547: 1546: 1542: 1511: 1510: 1506: 1504: 1501: 1500: 1461: 1460: 1456: 1454: 1451: 1450: 1401: 1397: 1393: 1389: 1374: 1370: 1350: 1346: 1342: 1338: 1323: 1319: 1279: 1278: 1274: 1246: 1245: 1241: 1239: 1236: 1235: 1216: 1213: 1212: 1172: 1169: 1168: 1149: 1146: 1145: 1138: 1113: 1109: 1102: 1096: 1092: 1090: 1065: 1064: 1060: 1059: 1036: 1035: 1031: 1030: 1028: 1011: 1008: 1007: 979: 976: 975: 942: 941: 937: 936: 913: 912: 908: 907: 905: 888: 885: 884: 881: 855: 850: 841: 837: 835: 832: 831: 800: 796: 792: 788: 773: 769: 751: 747: 745: 742: 741: 721: 717: 715: 712: 711: 685: 681: 679: 676: 675: 672: 643: 636: 632: 625: 623: 599: 595: 577: 573: 571: 568: 567: 543: 529:from a sampled 409: 310:current divider 260: 225:digital filters 166:high-cut filter 134:low-pass filter 126: 115: 109: 106: 63: 61: 51: 39: 28: 23: 22: 15: 12: 11: 5: 6548: 6538: 6537: 6532: 6527: 6522: 6517: 6515:Linear filters 6512: 6495: 6494: 6489: 6486: 6485: 6483: 6482: 6477: 6472: 6467: 6462: 6456: 6453: 6452: 6445: 6444: 6437: 6430: 6422: 6416: 6415: 6409: 6399: 6393: 6386: 6385:External links 6383: 6380: 6379: 6368: 6349: 6320: 6288: 6277: 6252: 6231: 6224: 6195: 6170: 6169: 6167: 6164: 6163: 6162: 6156: 6155: 6139: 6136: 6127: 6120: 6114: 6113: 6099: 6094: 6090: 6085: 6080: 6071: 6056: 6055: 6041: 6036: 6032: 6028: 6025: 6021: 6016: 6007: 5946: 5943: 5937: 5933: 5929: 5925: 5921: 5914:Cauer topology 5902: 5899: 5884: 5881: 5878: 5874: 5851: 5847: 5832: 5831: 5814: 5810: 5806: 5801: 5798: 5795: 5791: 5786: 5781: 5778: 5775: 5772: 5769: 5764: 5761: 5757: 5734: 5730: 5726: 5723: 5713: 5701: 5681: 5678: 5675: 5672: 5669: 5666: 5663: 5658: 5655: 5651: 5628: 5625: 5622: 5618: 5614: 5607: 5603: 5599: 5587: 5575: 5555: 5552: 5549: 5546: 5543: 5538: 5535: 5531: 5508: 5504: 5500: 5497: 5474: 5452: 5449: 5446: 5442: 5419: 5415: 5394: 5372: 5369: 5366: 5359: 5356: 5351: 5347: 5343: 5338: 5335: 5332: 5328: 5324: 5321: 5316: 5313: 5308: 5303: 5298: 5294: 5290: 5285: 5282: 5279: 5275: 5270: 5265: 5262: 5259: 5256: 5253: 5248: 5245: 5241: 5218: 5198: 5195: 5192: 5187: 5184: 5180: 5167: 5164: 5063: 5060: 5058: 5055: 5047:voltage source 5018:current source 4990:Main article: 4987: 4984: 4972: 4971: 4960: 4945: 4942: 4939: 4934: 4922:direct current 4910: 4909: 4905: 4898: 4897: 4883: 4880: 4876: 4871: 4866: 4863: 4858: 4852: 4847: 4828: 4827: 4813: 4810: 4807: 4804: 4800: 4795: 4789: 4786: 4783: 4779: 4774: 4768: 4763: 4731: 4728: 4724: 4720: 4711:of the filter 4691:consists of a 4673:Main article: 4670: 4667: 4665: 4662: 4660: 4657: 4639:is the filter 4629: 4628: 4614: 4611: 4608: 4605: 4601: 4596: 4593: 4553: 4550: 4507: 4506: 4491: 4471: 4463:Pole–zero plot 4376: 4373: 4368: 4364: 4344: 4341: 4331: 4330: 4281: 4279: 4272: 4266: 4263: 4249: 4246: 4223: 4218: 4214: 4209: 4206: 4202: 4197: 4193: 4188: 4183: 4179: 4175: 4155: 4150: 4146: 4141: 4138: 4134: 4129: 4125: 4120: 4115: 4111: 4107: 4087: 4044: 3973: 3953: 3950: 3947: 3943: 3937: 3933: 3908: 3904: 3900: 3881: 3880: 3869: 3861: 3857: 3853: 3850: 3847: 3844: 3841: 3838: 3835: 3831: 3826: 3821: 3817: 3802: 3801: 3787: 3784: 3779: 3775: 3769: 3765: 3761: 3758: 3751: 3747: 3741: 3737: 3733: 3730: 3724: 3721: 3696: 3692: 3676: 3675: 3664: 3656: 3652: 3648: 3645: 3641: 3636: 3633: 3630: 3607: 3604: 3601: 3598: 3594: 3589: 3584: 3580: 3565: 3564: 3553: 3549: 3544: 3540: 3537: 3534: 3528: 3522: 3518: 3514: 3511: 3508: 3479: 3475: 3441: 3437: 3433: 3429: 3425: 3410: 3409: 3398: 3390: 3386: 3382: 3379: 3376: 3370: 3366: 3360: 3357: 3345: 3342: 3339: 3335: 3331: 3328: 3325: 3322: 3319: 3316: 3311: 3307: 3303: 3300: 3295: 3291: 3269: 3268: 3257: 3246: 3241: 3233: 3229: 3225: 3222: 3219: 3214: 3211: 3205: 3199: 3196: 3193: 3189: 3181: 3170: 3165: 3157: 3153: 3149: 3146: 3143: 3137: 3133: 3127: 3121: 3117: 3109: 3104: 3100: 3082: 3081: 3070: 3063: 3059: 3052: 3049: 3046: 3042: 3038: 3033: 3029: 3021: 3018: 3015: 3010: 3006: 3002: 2997: 2993: 2969: 2964: 2960: 2955: 2952: 2948: 2943: 2939: 2934: 2929: 2925: 2921: 2895: 2874: 2869: 2865: 2860: 2857: 2853: 2848: 2844: 2839: 2834: 2830: 2826: 2800: 2777: 2773: 2761: 2760: 2749: 2743: 2740: 2737: 2726: 2722: 2719: 2713: 2710: 2707: 2704: 2701: 2698: 2689: 2685: 2682: 2679: 2676: 2667: 2634: 2631: 2628: 2617: 2613: 2610: 2604: 2600: 2596: 2593: 2590: 2587: 2572:into equation 2551: 2548: 2545: 2540: 2536: 2522: 2521: 2512: 2510: 2496: 2493: 2490: 2483: 2479: 2475: 2472: 2466: 2463: 2460: 2457: 2454: 2439: 2438: 2429: 2427: 2416: 2413: 2410: 2401: 2396: 2393: 2390: 2387: 2384: 2379: 2375: 2359: 2358: 2349: 2347: 2336: 2333: 2330: 2327: 2323: 2320: 2317: 2314: 2311: 2302: 2298: 2295: 2292: 2289: 2280: 2236: 2233: 2205: 2202: 2189: 2186: 2183: 2159: 2139: 2136: 2133: 2130: 2127: 2124: 2119: 2115: 2111: 2108: 2105: 2102: 2093: 2068: 2063: 2058: 2054: 2050: 2046: 2042: 2039: 2036: 2031: 2027: 2023: 2020: 2017: 2014: 2005: 1982: 1978: 1974: 1971: 1968: 1965: 1962: 1959: 1954: 1951: 1948: 1944: 1940: 1937: 1932: 1928: 1915: 1914:Error analysis 1912: 1911: 1910: 1897: 1893: 1889: 1886: 1883: 1880: 1877: 1874: 1869: 1866: 1863: 1859: 1855: 1852: 1847: 1843: 1817: 1813: 1809: 1804: 1800: 1779: 1776: 1773: 1770: 1764: 1761: 1756: 1752: 1747: 1743: 1722: 1719: 1716: 1713: 1707: 1704: 1701: 1696: 1692: 1687: 1683: 1658: 1653: 1649: 1645: 1641: 1637: 1634: 1623: 1622: 1609: 1605: 1601: 1598: 1595: 1592: 1589: 1586: 1583: 1580: 1577: 1574: 1571: 1568: 1565: 1562: 1556: 1553: 1550: 1545: 1541: 1538: 1535: 1532: 1529: 1526: 1520: 1517: 1514: 1509: 1485: 1482: 1479: 1476: 1470: 1467: 1464: 1459: 1447: 1446: 1435: 1430: 1427: 1424: 1421: 1418: 1415: 1412: 1409: 1404: 1400: 1396: 1392: 1388: 1385: 1382: 1377: 1373: 1369: 1366: 1361: 1358: 1353: 1349: 1345: 1341: 1337: 1334: 1331: 1326: 1322: 1318: 1315: 1312: 1309: 1306: 1303: 1300: 1297: 1294: 1288: 1285: 1282: 1277: 1273: 1270: 1267: 1264: 1261: 1255: 1252: 1249: 1244: 1220: 1200: 1197: 1194: 1191: 1188: 1185: 1182: 1179: 1176: 1156: 1153: 1137: 1134: 1133: 1132: 1116: 1112: 1108: 1105: 1099: 1095: 1089: 1083: 1080: 1077: 1071: 1068: 1063: 1057: 1054: 1051: 1045: 1042: 1039: 1034: 1027: 1024: 1021: 1018: 1015: 992: 989: 986: 983: 960: 957: 954: 948: 945: 940: 934: 931: 928: 922: 919: 916: 911: 904: 901: 898: 895: 892: 880: 877: 861: 858: 854: 849: 844: 840: 828: 827: 816: 813: 808: 803: 799: 795: 791: 787: 784: 781: 776: 772: 768: 765: 762: 759: 750: 724: 720: 699: 696: 693: 684: 671: 668: 667: 666: 652: 649: 646: 635: 631: 628: 622: 619: 616: 613: 610: 607: 598: 594: 591: 588: 585: 576: 542: 539: 531:digital signal 408: 405: 397:reconstruction 283:optical filter 259: 256: 233:moving average 128: 127: 42: 40: 33: 26: 9: 6: 4: 3: 2: 6547: 6536: 6533: 6531: 6528: 6526: 6523: 6521: 6518: 6516: 6513: 6511: 6508: 6507: 6505: 6492: 6487: 6481: 6478: 6476: 6473: 6471: 6468: 6466: 6463: 6461: 6458: 6457: 6454: 6450: 6443: 6438: 6436: 6431: 6429: 6424: 6423: 6420: 6413: 6410: 6407: 6403: 6400: 6397: 6394: 6392: 6389: 6388: 6377: 6372: 6366: 6365:9780750300582 6362: 6359: 6353: 6345: 6339: 6331: 6324: 6316: 6310: 6302: 6295: 6293: 6286: 6281: 6267:on 2013-09-27 6266: 6262: 6256: 6241: 6235: 6227: 6225:0-03-051648-X 6221: 6217: 6212: 6211: 6205: 6199: 6186: 6185: 6178: 6176: 6171: 6161: 6158: 6157: 6153: 6147: 6142: 6135: 6133: 6126: 6119: 6097: 6092: 6088: 6083: 6078: 6069: 6061: 6060: 6059: 6039: 6034: 6030: 6026: 6023: 6019: 6014: 6005: 5997: 5996: 5995: 5993: 5989: 5984: 5982: 5978: 5977:active filter 5975:to create an 5974: 5973:active device 5970: 5964: 5960: 5951: 5928:=4/3 farad, R 5919: 5915: 5910: 5906: 5898: 5882: 5879: 5876: 5872: 5849: 5845: 5835: 5812: 5808: 5804: 5799: 5796: 5793: 5789: 5784: 5779: 5776: 5770: 5762: 5759: 5755: 5732: 5728: 5724: 5721: 5714: 5699: 5679: 5676: 5673: 5670: 5664: 5656: 5653: 5649: 5626: 5623: 5620: 5616: 5612: 5605: 5601: 5597: 5588: 5573: 5553: 5550: 5544: 5536: 5533: 5529: 5506: 5502: 5498: 5495: 5488: 5487: 5486: 5472: 5450: 5447: 5444: 5440: 5417: 5413: 5392: 5383: 5367: 5357: 5354: 5349: 5345: 5341: 5336: 5333: 5330: 5326: 5322: 5319: 5314: 5311: 5306: 5301: 5296: 5292: 5288: 5283: 5280: 5277: 5273: 5268: 5263: 5260: 5254: 5246: 5243: 5239: 5230: 5216: 5193: 5185: 5182: 5178: 5163: 5161: 5157: 5153: 5149: 5145: 5141: 5137: 5134:, such as in 5133: 5129: 5124: 5122: 5117: 5113: 5109: 5105: 5101: 5097: 5093: 5089: 5085: 5081: 5077: 5068: 5054: 5052: 5048: 5044: 5040: 5036: 5032: 5029: 5026: 5021: 5019: 5015: 5011: 5007: 5003: 4999: 4993: 4983: 4981: 4977: 4969: 4965: 4961: 4932: 4923: 4919: 4918: 4917: 4915: 4906: 4903: 4902: 4901: 4881: 4878: 4874: 4869: 4864: 4861: 4856: 4845: 4837: 4836: 4835: 4834:per second): 4833: 4811: 4808: 4805: 4802: 4798: 4793: 4787: 4784: 4781: 4777: 4772: 4761: 4753: 4752: 4751: 4749: 4745: 4729: 4726: 4722: 4718: 4710: 4709:time constant 4706: 4702: 4698: 4694: 4690: 4681: 4676: 4656: 4654: 4650: 4646: 4642: 4641:time constant 4638: 4634: 4612: 4609: 4606: 4603: 4599: 4594: 4591: 4574: 4573: 4572: 4569: 4567: 4563: 4559: 4549: 4547: 4542: 4540: 4536: 4532: 4528: 4527:Bessel filter 4524: 4520: 4516: 4512: 4492: 4489: 4485: 4480: 4476: 4472: 4470: 4468: 4464: 4458: 4455:as well as a 4454: 4450: 4446: 4442: 4438: 4430: 4426: 4425: 4424: 4422: 4418: 4414: 4410: 4406: 4402: 4394: 4390: 4374: 4371: 4366: 4362: 4354: 4349: 4340: 4337: 4327: 4324: 4316: 4306: 4302: 4298: 4292: 4291: 4287: 4282:This section 4280: 4276: 4271: 4270: 4262: 4260: 4255: 4254:sinc function 4245: 4243: 4239: 4238: 4216: 4212: 4207: 4204: 4200: 4195: 4191: 4186: 4181: 4177: 4148: 4144: 4139: 4136: 4132: 4127: 4123: 4118: 4113: 4109: 4085: 4077: 4074: 4073:time constant 4070: 4066: 4062: 4055: 4051: 4047: 4043: 4041: 4037: 4033: 4026: 4022: 4018: 4014: 4010: 4007: 4003: 4000: 3996: 3992: 3988: 3984: 3981: 3977: 3972: 3970: 3965: 3951: 3948: 3945: 3941: 3935: 3922: 3906: 3902: 3898: 3890: 3867: 3859: 3851: 3848: 3842: 3839: 3836: 3829: 3824: 3819: 3815: 3807: 3806: 3805: 3785: 3782: 3777: 3773: 3767: 3759: 3756: 3749: 3745: 3739: 3731: 3728: 3722: 3719: 3712: 3711: 3710: 3694: 3690: 3662: 3654: 3650: 3646: 3643: 3639: 3634: 3631: 3628: 3605: 3602: 3599: 3596: 3592: 3587: 3582: 3578: 3570: 3569: 3568: 3551: 3547: 3542: 3538: 3535: 3532: 3526: 3520: 3512: 3509: 3506: 3499: 3498: 3497: 3477: 3463: 3459: 3458:time constant 3439: 3435: 3431: 3427: 3423: 3415: 3396: 3388: 3380: 3377: 3374: 3368: 3358: 3355: 3343: 3340: 3337: 3333: 3326: 3323: 3320: 3314: 3309: 3305: 3301: 3298: 3293: 3289: 3281: 3280: 3279: 3278: 3274: 3255: 3244: 3239: 3231: 3223: 3220: 3217: 3212: 3209: 3203: 3197: 3194: 3191: 3187: 3179: 3168: 3163: 3155: 3147: 3144: 3141: 3135: 3125: 3119: 3115: 3107: 3102: 3098: 3090: 3089: 3088: 3087: 3068: 3061: 3050: 3047: 3044: 3040: 3036: 3031: 3027: 3019: 3016: 3013: 3008: 3004: 3000: 2995: 2991: 2983: 2982: 2981: 2962: 2958: 2953: 2950: 2946: 2941: 2937: 2932: 2927: 2923: 2893: 2867: 2863: 2858: 2855: 2851: 2846: 2842: 2837: 2832: 2828: 2798: 2775: 2747: 2741: 2738: 2724: 2720: 2711: 2708: 2705: 2699: 2687: 2683: 2677: 2665: 2657: 2656: 2655: 2653: 2652: 2632: 2629: 2615: 2611: 2602: 2598: 2591: 2585: 2577: 2576: 2571: 2570: 2546: 2538: 2534: 2520: 2513: 2511: 2494: 2491: 2481: 2477: 2473: 2464: 2458: 2452: 2445: 2444: 2437: 2430: 2428: 2411: 2399: 2394: 2391: 2385: 2377: 2373: 2365: 2364: 2357: 2350: 2348: 2331: 2325: 2321: 2318: 2312: 2300: 2296: 2290: 2278: 2270: 2269: 2266: 2264: 2260: 2253: 2248: 2244: 2242: 2232: 2230: 2226: 2222: 2218: 2211: 2201: 2187: 2181: 2173: 2157: 2134: 2131: 2125: 2122: 2117: 2113: 2109: 2103: 2091: 2082: 2061: 2056: 2052: 2048: 2044: 2040: 2037: 2029: 2025: 2021: 2015: 2003: 1980: 1976: 1969: 1966: 1963: 1957: 1952: 1949: 1946: 1942: 1938: 1935: 1930: 1926: 1895: 1891: 1884: 1881: 1878: 1872: 1867: 1864: 1861: 1857: 1853: 1850: 1845: 1841: 1833: 1832: 1831: 1815: 1811: 1807: 1802: 1798: 1774: 1771: 1754: 1750: 1745: 1741: 1717: 1714: 1694: 1690: 1685: 1681: 1671: 1656: 1651: 1647: 1643: 1639: 1635: 1632: 1607: 1603: 1596: 1593: 1590: 1584: 1578: 1572: 1569: 1566: 1543: 1539: 1536: 1530: 1527: 1507: 1499: 1498: 1497: 1480: 1477: 1457: 1425: 1419: 1416: 1413: 1402: 1398: 1394: 1390: 1386: 1383: 1375: 1371: 1367: 1359: 1356: 1351: 1347: 1343: 1339: 1335: 1332: 1324: 1320: 1316: 1310: 1304: 1301: 1298: 1275: 1271: 1265: 1262: 1242: 1234: 1233: 1232: 1218: 1198: 1195: 1192: 1189: 1186: 1183: 1180: 1177: 1174: 1154: 1151: 1143: 1114: 1110: 1106: 1103: 1097: 1093: 1087: 1078: 1061: 1052: 1032: 1025: 1019: 1013: 1006: 1005: 1004: 987: 981: 955: 938: 929: 909: 902: 896: 890: 876: 859: 856: 852: 847: 842: 838: 814: 806: 801: 797: 793: 789: 785: 782: 774: 770: 766: 760: 748: 740: 739: 738: 722: 718: 694: 682: 650: 647: 633: 629: 620: 617: 614: 608: 596: 592: 586: 574: 566: 565: 564: 562: 555: 550: 546: 541:Time response 538: 536: 532: 528: 524: 519: 516: 512: 508: 503: 501: 497: 493: 489: 484: 480: 478: 477:sinc function 474: 470: 466: 462: 458: 454: 450: 442: 438: 434: 429: 422: 418: 417:sinc function 413: 404: 402: 398: 394: 390: 385: 384: 382: 376: 371: 369: 365: 361: 358:signals (and 357: 353: 349: 348:DSL splitters 344: 342: 341:time constant 338: 334: 330: 326: 322: 317: 315: 311: 307: 303: 299: 295: 290: 288: 284: 279: 275: 273: 269: 265: 255: 253: 249: 245: 240: 238: 234: 230: 226: 222: 218: 214: 210: 205: 204:frequencies. 203: 199: 195: 191: 186: 182: 177: 175: 171: 167: 163: 162:filter design 159: 155: 151: 147: 143: 139: 135: 124: 121: 113: 102: 99: 95: 92: 88: 85: 81: 78: 74: 71: –  70: 66: 65:Find sources: 59: 55: 49: 48: 43:This article 41: 37: 32: 31: 19: 6459: 6371: 6357: 6352: 6329: 6323: 6300: 6280: 6269:. Retrieved 6265:the original 6255: 6244:. Retrieved 6234: 6209: 6198: 6188:, retrieved 6183: 6124: 6117: 6115: 6057: 5985: 5968: 5966: 5904: 5836: 5833: 5384: 5231: 5169: 5156:second-order 5155: 5125: 5073: 5057:Second order 5045:driven by a 5041:, either in 5022: 5012:driven by a 5004:composed of 4995: 4973: 4911: 4899: 4829: 4686: 4644: 4636: 4632: 4630: 4570: 4555: 4543: 4538: 4530: 4514: 4508: 4474: 4460: 4428: 4420: 4412: 4398: 4392: 4388: 4338: 4334: 4319: 4310: 4295:Please help 4283: 4251: 4235: 4075: 4061:proportional 4058: 4053: 4049: 4045: 4035: 4029: 4024: 4020: 4016: 4012: 4008: 4005: 4001: 3998: 3994: 3990: 3986: 3982: 3979: 3975: 3966: 3920: 3888: 3882: 3803: 3677: 3566: 3461: 3413: 3411: 3272: 3270: 3083: 2762: 2649: 2573: 2567: 2525: 2514: 2431: 2351: 2256: 2241:discretizing 2238: 2214: 2172:time variant 2171: 2081:time variant 2080: 1917: 1672: 1624: 1449:Solving for 1448: 1139: 882: 829: 673: 558: 544: 520: 504: 485: 481: 446: 432: 386: 378: 375:synthesisers 372: 367: 345: 325:loudspeakers 318: 291: 286: 280: 276: 261: 241: 208: 206: 201: 197: 193: 189: 184: 180: 178: 169: 165: 140:that passes 133: 131: 116: 107: 97: 90: 83: 76: 64: 52:Please help 47:verification 44: 6204:Sedra, Adel 5940:=1/2 henry. 5104:capacitance 5076:RLC circuit 4664:First order 4566:Z-transform 4531:knee curves 4488:RLC circuit 4415:the filter 4069:exponential 2263:capacitance 2243:the model. 1140:A discrete 500:phase shift 469:convolution 339:is another 272:electronics 209:hiss filter 188:filters as 179:In optics, 6504:Categories 6271:2013-09-24 6246:2013-09-24 6190:2017-10-04 6166:References 6130:, and the 5957:See also: 5116:LC circuit 5100:inductance 5096:resistance 5062:RLC filter 4511:asymptotes 4467:RC circuit 4417:attenuates 4313:March 2015 4040:refactored 3969:pseudocode 2885:, and let 2083:, such as 674:If we let 433:Power gain 366:of wires ( 337:integrator 321:subwoofers 190:short-pass 154:attenuates 80:newspapers 6530:Acoustics 6338:cite book 6309:cite book 6070:ω 6027:π 5932:=1 ohm, L 5805:⋅ 5780:− 5777:≈ 5725:≫ 5551:≈ 5499:≪ 5342:⋅ 5320:⋅ 5289:⋅ 5264:− 5092:capacitor 5010:inductors 5006:resistors 4998:RL filter 4986:RL filter 4976:Bode plot 4914:reactance 4865:τ 4846:ω 4806:π 4788:τ 4785:π 4719:τ 4705:reactance 4701:capacitor 4669:RC filter 4604:τ 4560:of their 4535:resonance 4401:Bode plot 4363:ω 4284:does not 4205:… 4137:… 4086:α 3946:α 3942:≈ 3932:Δ 3903:≪ 3899:α 3856:Δ 3852:π 3843:α 3840:− 3830:α 3764:Δ 3760:π 3736:Δ 3732:π 3720:α 3647:π 3600:π 3543:α 3539:α 3536:− 3517:Δ 3474:Δ 3436:≤ 3432:α 3428:≤ 3385:Δ 3365:Δ 3356:α 3341:− 3327:α 3324:− 3302:α 3245:⏞ 3228:Δ 3195:− 3169:⏞ 3152:Δ 3132:Δ 3058:Δ 3048:− 3037:− 3001:− 2951:… 2856:… 2772:Δ 2739:⁡ 2721:⁡ 2684:− 2630:⁡ 2612:⁡ 2492:⁡ 2474:⁡ 2297:− 2252:RC filter 2185:→ 2132:ω 2126:⁡ 2053:ω 2049:− 2041:− 1970:β 1967:− 1950:− 1939:β 1885:β 1882:− 1865:− 1854:β 1648:ω 1644:− 1633:β 1597:β 1594:− 1570:− 1540:β 1417:− 1399:ω 1395:− 1387:− 1368:− 1348:ω 1344:− 1336:− 1302:− 1272:− 1111:ω 1094:ω 839:ω 798:ω 794:− 786:− 648:⁡ 630:⁡ 615:− 554:RC filter 492:windowing 488:real-time 471:with its 463:and is a 360:high-pass 294:RC filter 264:acoustics 252:band-stop 248:band-pass 198:high-pass 194:long-pass 181:high-pass 146:frequency 6160:Baseband 6138:See also 6132:stopband 5112:resonate 5090:, and a 5088:inductor 5084:resistor 5051:parallel 5039:inductor 5035:resistor 5025:analogue 4699:, and a 4693:resistor 4653:passband 4484:Q factor 3997:RC) 3985:lowpass( 3983:function 2654:so that 533:. Real 509:via the 395:and for 393:sampling 329:harmonic 306:parallel 287:longpass 258:Examples 229:blurring 211:used in 202:low-pass 185:low-pass 110:May 2023 5986:In the 5121:damping 5037:and an 5014:voltage 4908:amount. 4832:radians 4689:circuit 4647:is the 4409:rolloff 4305:removed 4290:sources 4237:inertia 3919:, then 1496:we get 1003:we get 391:before 144:with a 142:signals 94:scholar 18:Lowpass 6363:  6222:  5969:active 5961:, and 5132:tuning 5102:, and 5049:or in 5043:series 5000:is an 4962:Since 4920:Since 4643:, and 4631:where 4584:Output 4441:decade 4437:octave 4025:return 4004:y 3678:note 2578:gives 2526:where 1625:Where 1167:where 830:where 559:Using 268:optics 138:filter 96:  89:  82:  75:  67:  6535:Sound 5992:hertz 5086:, an 4587:Input 4539:above 4433:6 dB) 4421:order 3883:If 3351:where 2215:Many 459:is a 354:from 314:below 213:audio 168:, or 136:is a 101:JSTOR 87:books 6361:ISBN 6344:link 6315:link 6220:ISBN 5981:gain 5008:and 4978:and 4697:load 4649:gain 4465:and 4461:See 4457:pole 4453:zero 4288:any 4286:cite 4050:from 4032:loop 4030:The 4017:from 4009:real 4002:real 3995:real 3993:dt, 3991:real 3987:real 3804:and 3682:and 2223:and 1733:and 1211:and 521:The 475:, a 415:The 379:See 364:pair 356:POTS 270:and 200:and 192:and 183:and 152:and 73:news 5967:An 5138:or 5074:An 5016:or 4744:tau 4299:by 4046:for 4013:for 4006:var 3999:var 3989:x, 3907:0.5 3621:so 2898:out 2729:out 2692:out 2620:out 2404:out 2305:out 2123:sin 2008:out 753:out 638:out 579:out 447:An 399:in 370:). 352:DSL 316:.) 281:An 254:). 250:or 56:by 6506:: 6340:}} 6336:{{ 6311:}} 6307:{{ 6291:^ 6218:. 6216:60 6174:^ 5747:: 5641:: 5521:: 5146:, 5098:, 4655:. 4525:, 4521:, 4473:A 4427:A 4076:RC 4054:to 4052:2 4048:i 4027:y 4021:to 4019:2 4015:i 3980:RC 3976:dt 3964:. 3921:RC 3889:RC 3496:, 3462:RC 3359::= 3273:RC 2803:in 2670:in 2283:in 2265:: 2200:. 2096:in 687:in 601:in 437:dB 403:. 377:. 274:. 266:, 223:, 215:, 176:. 132:A 6441:e 6434:t 6427:v 6346:) 6317:) 6274:. 6249:. 6228:. 6128:1 6125:R 6123:/ 6121:2 6118:R 6098:C 6093:2 6089:R 6084:1 6079:= 6074:c 6040:C 6035:2 6031:R 6024:2 6020:1 6015:= 6010:c 6006:f 5938:3 5934:1 5930:4 5926:2 5922:c 5920:ω 5883:F 5880:S 5877:F 5873:f 5850:c 5846:f 5813:2 5809:f 5800:F 5797:S 5794:F 5790:f 5785:K 5774:) 5771:f 5768:( 5763:P 5760:L 5756:H 5733:c 5729:f 5722:f 5712:. 5700:Q 5680:Q 5677:K 5674:j 5671:= 5668:) 5665:f 5662:( 5657:P 5654:L 5650:H 5627:F 5624:S 5621:F 5617:f 5613:= 5606:c 5602:f 5598:f 5586:. 5574:K 5554:K 5548:) 5545:f 5542:( 5537:P 5534:L 5530:H 5507:c 5503:f 5496:f 5473:Q 5451:F 5448:S 5445:F 5441:f 5418:c 5414:f 5393:f 5371:) 5368:1 5365:( 5358:1 5355:+ 5350:c 5346:f 5337:F 5334:S 5331:F 5327:f 5323:j 5315:Q 5312:1 5307:+ 5302:2 5297:c 5293:f 5284:F 5281:S 5278:F 5274:f 5269:K 5261:= 5258:) 5255:f 5252:( 5247:P 5244:L 5240:H 5217:f 5197:) 5194:f 5191:( 5186:P 5183:L 5179:H 4944:t 4941:u 4938:o 4933:V 4882:C 4879:R 4875:1 4870:= 4862:1 4857:= 4851:c 4812:C 4809:R 4803:2 4799:1 4794:= 4782:2 4778:1 4773:= 4767:c 4762:f 4730:C 4727:R 4723:= 4645:K 4637:τ 4633:s 4613:1 4610:+ 4607:s 4600:1 4595:K 4592:= 4503:n 4499:n 4495:n 4490:. 4469:. 4393:n 4389:n 4375:1 4372:= 4367:0 4326:) 4320:( 4315:) 4311:( 4307:. 4293:. 4222:) 4217:n 4213:x 4208:, 4201:, 4196:2 4192:x 4187:, 4182:1 4178:x 4174:( 4154:) 4149:n 4145:y 4140:, 4133:, 4128:2 4124:y 4119:, 4114:1 4110:y 4106:( 4036:n 3952:C 3949:R 3936:T 3885:α 3868:. 3860:T 3849:2 3846:) 3837:1 3834:( 3825:= 3820:c 3816:f 3786:1 3783:+ 3778:c 3774:f 3768:T 3757:2 3750:c 3746:f 3740:T 3729:2 3723:= 3695:c 3691:f 3680:α 3663:, 3655:c 3651:f 3644:2 3640:1 3635:= 3632:C 3629:R 3606:C 3603:R 3597:2 3593:1 3588:= 3583:c 3579:f 3552:. 3548:) 3533:1 3527:( 3521:T 3513:= 3510:C 3507:R 3494:α 3478:T 3454:α 3440:1 3424:0 3397:. 3389:T 3381:+ 3378:C 3375:R 3369:T 3344:1 3338:i 3334:y 3330:) 3321:1 3318:( 3315:+ 3310:i 3306:x 3299:= 3294:i 3290:y 3256:. 3240:) 3232:T 3224:+ 3221:C 3218:R 3213:C 3210:R 3204:( 3198:1 3192:i 3188:y 3180:+ 3164:) 3156:T 3148:+ 3145:C 3142:R 3136:T 3126:( 3120:i 3116:x 3108:= 3103:i 3099:y 3069:. 3062:T 3051:1 3045:i 3041:y 3032:i 3028:y 3020:C 3017:R 3014:= 3009:i 3005:y 2996:i 2992:x 2968:) 2963:n 2959:y 2954:, 2947:, 2942:2 2938:y 2933:, 2928:1 2924:y 2920:( 2894:v 2873:) 2868:n 2864:x 2859:, 2852:, 2847:2 2843:x 2838:, 2833:1 2829:x 2825:( 2799:v 2776:T 2748:. 2742:t 2736:d 2725:v 2718:d 2712:C 2709:R 2706:= 2703:) 2700:t 2697:( 2688:v 2681:) 2678:t 2675:( 2666:v 2651:V 2633:t 2627:d 2616:v 2609:d 2603:C 2599:= 2595:) 2592:t 2589:( 2586:i 2575:I 2569:Q 2564:t 2550:) 2547:t 2544:( 2539:c 2535:Q 2519:) 2517:I 2515:( 2495:t 2489:d 2482:c 2478:Q 2471:d 2465:= 2462:) 2459:t 2456:( 2453:i 2436:) 2434:Q 2432:( 2415:) 2412:t 2409:( 2400:v 2395:C 2392:= 2389:) 2386:t 2383:( 2378:c 2374:Q 2356:) 2354:V 2352:( 2335:) 2332:t 2329:( 2326:i 2322:R 2319:= 2316:) 2313:t 2310:( 2301:v 2294:) 2291:t 2288:( 2279:v 2212:. 2188:0 2182:T 2158:T 2138:) 2135:t 2129:( 2118:i 2114:V 2110:= 2107:) 2104:t 2101:( 2092:v 2067:) 2062:t 2057:0 2045:e 2038:1 2035:( 2030:i 2026:V 2022:= 2019:) 2016:t 2013:( 2004:v 1981:n 1977:v 1973:) 1964:1 1961:( 1958:+ 1953:1 1947:n 1943:V 1936:= 1931:n 1927:V 1896:n 1892:v 1888:) 1879:1 1876:( 1873:+ 1868:1 1862:n 1858:V 1851:= 1846:n 1842:V 1816:i 1812:V 1808:= 1803:n 1799:v 1778:) 1775:T 1772:n 1769:( 1763:n 1760:i 1755:v 1751:= 1746:n 1742:v 1721:) 1718:T 1715:n 1712:( 1706:t 1703:u 1700:o 1695:v 1691:= 1686:n 1682:V 1657:T 1652:0 1640:e 1636:= 1608:i 1604:V 1600:) 1591:1 1588:( 1585:+ 1582:) 1579:T 1576:) 1573:1 1567:n 1564:( 1561:( 1555:t 1552:u 1549:o 1544:v 1537:= 1534:) 1531:T 1528:n 1525:( 1519:t 1516:u 1513:o 1508:v 1484:) 1481:T 1478:n 1475:( 1469:t 1466:u 1463:o 1458:v 1434:) 1429:) 1426:T 1423:) 1420:1 1414:n 1411:( 1408:( 1403:0 1391:e 1384:1 1381:( 1376:i 1372:V 1365:) 1360:T 1357:n 1352:0 1340:e 1333:1 1330:( 1325:i 1321:V 1317:= 1314:) 1311:T 1308:) 1305:1 1299:n 1296:( 1293:( 1287:t 1284:u 1281:o 1276:v 1269:) 1266:T 1263:n 1260:( 1254:t 1251:u 1248:o 1243:v 1219:T 1199:. 1196:. 1193:. 1190:, 1187:1 1184:, 1181:0 1178:= 1175:n 1155:T 1152:n 1115:0 1107:+ 1104:s 1098:0 1088:= 1082:) 1079:s 1076:( 1070:n 1067:i 1062:V 1056:) 1053:s 1050:( 1044:t 1041:u 1038:o 1033:V 1026:= 1023:) 1020:s 1017:( 1014:H 991:) 988:s 985:( 982:H 959:) 956:s 953:( 947:n 944:i 939:V 933:) 930:s 927:( 921:t 918:u 915:o 910:V 903:= 900:) 897:s 894:( 891:H 860:C 857:R 853:1 848:= 843:0 815:, 812:) 807:t 802:0 790:e 783:1 780:( 775:i 771:V 767:= 764:) 761:t 758:( 749:v 723:i 719:V 698:) 695:t 692:( 683:v 651:t 645:d 634:v 627:d 621:C 618:R 612:) 609:t 606:( 597:v 593:= 590:) 587:t 584:( 575:v 383:. 123:) 117:( 112:) 108:( 98:· 91:· 84:· 77:· 50:. 20:)

Index

Lowpass

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