mql5/Indicators/MyIndicators/Windowed_Momentum_Pro.md

Windowed Momentum Professional

1. Summary (Introduction)

The Windowed Momentum Pro is an oscillator developed from the concepts in John Ehlers' "Windowing" article. Instead of applying the advanced FIR filters to the price, this indicator applies them to a momentum source (Close - Open).

The indicator calculates a weighted average of the bar-by-bar momentum over a given period, using a selectable windowing function (SMA, Triangular, or Hann).

The result is a smooth, zero-mean oscillator that measures the underlying strength and direction of momentum. The use of the Hann window is particularly effective, as it creates a much cleaner and less noisy oscillator than a simple momentum calculation.

2. Mathematical Foundations and Calculation Logic

The indicator is a weighted moving average of the Close - Open value of each bar.

Calculation Steps (Algorithm)

1. Calculate Momentum Source: For each bar, the source data is calculated as Momentum = Close - Open.
2. Apply Windowing Function: A weighted moving average is calculated on this Momentum data series using the selected windowing function (SMA, Triangular, or Hann) over the N-period lookback window. The calculation is identical to the Windowed MA Pro indicator, but applied to a different data source.

3. MQL5 Implementation Details

• Unified Calculator (Windowed_MA_Calculator.mqh): This indicator uses the exact same, powerful calculator engine as the Windowed_MA_Pro. The only difference is that it is initialized in SOURCE_MOMENTUM mode.
• Heikin Ashi Integration: The indicator fully supports calculation on smoothed Heikin Ashi data (HA Close - HA Open).
• FIR-based Logic: This is a non-recursive (FIR) filter.
• Stability via Full Recalculation: The indicator employs a full recalculation on every OnCalculate call.

4. Parameters

• Window Type (InpWindowType): Allows the user to select the weighting function: SMA, Triangular, or Hann. Hann is recommended for the smoothest output.
• Period (InpPeriod): The lookback period (N) for the momentum averaging.
• Candle Source (InpCandleSource): Selects between Standard and Heikin Ashi candles.

5. Usage and Interpretation

The Windowed Momentum is a classic zero-mean oscillator used for identifying momentum shifts and potential reversals.

• Zero-Line Crossover:
  • A cross above the zero line indicates that bullish momentum is taking control.
  • A cross below the zero line indicates that bearish momentum is dominant.
• Divergence: This is one of the most powerful ways to use the indicator.
  • Bullish Divergence: Price makes a new lower low, but the Windowed Momentum makes a higher low. This signals weakening sell pressure and a potential bottom.
  • Bearish Divergence: Price makes a new higher high, but the Windowed Momentum makes a lower high. This signals weakening buy pressure and a potential top.
• Combined with Windowed MA: Use the Windowed_MA_Pro to define the main trend. Then, use the Windowed_Momentum_Pro to time entries. In an uptrend (price > W-MA), look for the W-Momentum to form a valley (ideally below zero) and turn up as a high-probability entry signal.

Combined Strategy with Windowed MA (Primary Use)

This oscillator is designed to be used in conjunction with its companion indicator, the Windowed_MA_Pro. The relationship between the two provides a powerful timing signal.

• The Zero-Cross Predicts the MA's Turning Point: The most important signal is the crossing of the zero line, as it directly corresponds to the turning points of the Windowed_MA.
  • Buy Signal: When the Windowed_Momentum line crosses above the zero line, it signals that the Windowed_MA on the main chart is forming a trough (a bottom). This is a signal that the downtrend momentum has ended and an uptrend is beginning.
  • Sell Signal: When the Windowed_Momentum line crosses below the zero line, it signals that the Windowed_MA is forming a peak (a top). This indicates the end of uptrend momentum.

This strategy allows a trader to use the Momentum oscillator as a leading indicator to anticipate the turning points of the smoother, lagging Windowed_MA.