# Dictionary Definition

quadrature n : the construction of a square
having the same area as some other figure

# User Contributed Dictionary

## English

### Noun

- the process of making something square; squaring
- the process of constructing a square having the same area as a given plane figure, or of computing that area
- a situation in which three celestial bodies form a right-angled triangle
- the condition in which the phase angle between two alternating quantities is 90°

#### Derived terms

#### Translations

squaring

- German: Quadrieren

mathematics

- German: Quadratur

astronomy

- German: Quadratur

physics: condition in which the phase angle is
90 degrees

- Korean: 직교

## Italian

### Noun

quadrature- Plural of quadratura

# Extensive Definition

Quadrature, derived from Latin quadrare, may
refer to:

In signal processing:

- Quadrature amplitude modulation (QAM), a modulation method of using both a carrier wave and a 'quadrature' carrier wave that is 90° out of phase with the main carrier
- Quadrature phase, oscillations that are said to be in quadrature if they are separated in phase by 90° (π/2, or λ/4)
- Quadrature filter, the analytic signal of a real-valued filter
- Quadrature coupler, see under chapter five in Power dividers and directional couplers

In mathematics:

- Quadrature of the circle (also squaring the circle), in geometry, the problem of constructing a square and circle of equal area, impossible using only an unmarked straight-edge and compass
- Summing in quadrature means summing the squares of numbers, then taking the square root, as used in error analysis
- Numerical quadrature, the numerical calculation of the area under a curve, or more generally, using numerical integration to calculate a definite integral

Quadrature may also refer to:

- In motion control, quadrature encoder is a rotary encoder or linear encoder giving both the relative position and the direction of motion of a shaft
- In astronomy, quadrature occurs when two celestial bodies appear 90° apart from one another as viewed from a third celestial body. As an example, the Moon and the Sun are in quadrature with respect to the Earth when the Moon is in its exact first quarter or last quarter phases. The symbol for astronomical quadrature is a hollow square

quadrature in German: Quadratur
(Begriffsklärung)

quadrature in Spanish: Cuadratura

quadrature in French: Quadrature

quadrature in Italian:
Quadratura