Below is the definitive short list traders
(coders, quants, and magazine readers) encounter most from Ehlers.
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MESA (Maximum Entropy Spectrum Analysis)
Category: Cycle detection
Why it’s important:

• This is Ehlers’ signature invention.

• It analyzes price like a signal to find the dominant cycle length in real time.

• Helps create adaptive moving averages, filters, and oscillators.

Used for:

• Adapting indicator length dynamically

• Cycle-based entries and exits

• Avoiding fixed-period indicators (like standard RSI 14)

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Ehlers’ Instantaneous Trendline

Category: Zero-lag trend detection
Features:

• Attempts to extract trend with nearly no lag.

• Reacts faster than SMA/EMA while staying smoother.

Used for:

• Trend-following systems

• Fast directional bias without repainting

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Super Smoother Filter

Category: Low-lag smoothing
Description:

• A 2-pole filter that removes noise while keeping responsiveness.

• Works like a zero-lag EMA on steroids.

Used for:

• Creating smoother versions of RSI, MACD, Stochastics

• Reducing whipsaw during choppy forex markets

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Roofing Filter

Category: Band-pass filter
Purpose:

• Removes both low-frequency drift (trend) and high-frequency noise.

• Leaves only the tradable cyclical component of the price.

Used for:

• Oscillator construction

• Cycle-based scalping

• Indicators like Ehlers’ Sinewave

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Ehlers Sine Wave / Lead Sine

Category: Cycle oscillator
Features:

• Plots a sine and lead-sine line.

• Shows turning points before RSI/MACD do.

Used for:

• Early cycle reversals

• Identifying peak/trough moments

• Sideways market scalping

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Fisher Transform (Ehlers Fisher)

Category: Probability-based oscillator
Why it’s popular:

• Converts price into a Gaussian-like distribution, making turning points more statistically meaningful.

• Extremely sharp turning points.

Used for:

• Reversal signals

• Converting price swings into clear highs/lows

• Foundation of many MT4/MT5 custom indicators

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Laguerre Filter / Laguerre RSI

Category: Recursive filter
Purpose:

• Smooths data with almost no lag and incredibly little noise.

• Uses gamma (γ) to control memory depth.

Used for:

• Building “no-lag RSI,” “no-lag MACD,” etc.

• Intraday scalping

• Eliminating false signals

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Instantaneous Frequency & Hilbert Transform Tools

Category: Advanced DSP
Includes:

• Hilbert Transform

• Quadrature components

• Dominant cycle measurement

Used for:

• Adaptive indicators

• Determining if market is trending or cycling

• Identifying cycle phase (peak, trough, slope)

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Mesa Adaptive Moving Average (MAMA) & FAMA

Category: Adaptive moving averages
Features:

• Uses the measured dominant cycle to adjust speed.

• Fast in trends, slow in chop — automatically.

Used for:

• Trend trading

• Filtering noise

• Adaptive support/resistance

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Decycler / De-Trending Indicator

Category: Removing cycles
Purpose:

• Instead of filtering noise to isolate cycles, this filter removes cycles to show pure trend.

Used for:

• Trend direction without oscillations

• Hybrid cycle/trend systems when paired with Roofing Filter

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Honorable Mentions

These are also referenced frequently in S&C Magazine:

• Zero-Lag EMA — modified EMA formula with reduced lag

• Adaptive RSI — RSI using dominant cycle length

• Homodyne Discriminator — cycle measurement technique

• Band-Pass filters for scalping systems

• Gaussian filters for ultra-smooth lines

• Ehlers’ Cyber Cycle — a highly responsive oscillator

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Why Ehlers Matters for Coders

Ehlers is the bridge between engineering DSP theory and trading indicators.
He uses:

• Digital filters

• Spectral analysis

• Hilbert transforms

• Smoothing algorithms

• Zero-lag techniques

This makes his indicators codable, modular, and mathematically consistent.

That’s why platforms like:

• MT4/MT5

• TradingView

• NinjaTrader

• ThinkorSwim

• AmiBroker

all have large libraries of Ehlers-based indicators.
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