Tunable quadrature phase shifter using an all-pass circuit
AssigneeKoninklijke Philips Electronics N.V.
InventorMihai Adrian Tiberiu Sanduleanu
Life of this patent
Estimating the term…
Abstract
The present invention relates to a tunable quadrature phase shifter comprising an input (IN) for inputting an input signal (vin), splitting means (10) for splitting the input signal into two essentially orthogonal first and second signals (i1, i2), adding means (6) for adding said first and second signals (i1, i2), subtracting means (7) for subtracting said first and second signals (i1, i2), a first output (OUT+) for outputting a first output signal (vo1) based on the output signal from said adding means (6), and a second output (OUT−) for outputting a second output signal (vo2) based on the output signal from said subtracting means (7), wherein that said splitting means (10) is provided as an all-pass.
Claims11
Tunable quadrature phase shifter comprising
- an input means (IN) for inputting an input signal,
- a transimpedance converter that converts the input signal from a voltage signal to a current signal,
- splitting means (10) for splitting the input signal into two essentially orthogonal first and second signals (i1, i2),
- adding means (6) for adding said first and second signals (i1, i2),
- subtracting means (7) for subtracting said first and second signals (i1, i2),
- a first output (OUT−) for outputting a first output signal (vo1) based on the output signal from said adding means (6), and
- a second output (OUT−) for outputting a second output signal (vo2) based on the output signal from said subtracting means (7), characterized in that said splitting means (10) is provided as an all-pass circuit, which produces two quadrature signals with equal amplitude without using a feedback loop.
A tunable quadrature phase shifter comprising:
- an input means (IN) for inputting an input signal (vin;
- iin),
- splitting means (10) for splitting the input signal into two essentially orthogonal first and second signals (i1, i2),
- adding means (6) for adding said first and second signals (i1, i2),
- subtracting means (7) for subtracting said first and second signals (i1, i2),
- a first output (OUT+) for outputting a first output signal (vo1) based on the output signal from said adding means (6), and
- a second output (OUT−) for outputting a second output signal (vo2) based on the output signal from said subtracting means (7), characterized by at least:
- a first transistor (T1) wit its collector connected to its base and its emitter coupled to a predetermined potential,
- a second transistor (T2) with its base connected to the base of said first transistor and its emitter coupled to said predetermined fixed potential, and
- a capacitor (C) coupled between the junction of the bases of said first and second transistor (T1, T2) and said predetermined potential.
A tunable quadrature phase shifter comprising:
- a first input (In+) for inputting an input signal,
- a second input (In−) for inputting an inverse input signal,
- splitting means (10) for splitting the input signal into two essentially orthogonal first and second signals (i1, i2),
- adding means (6) for adding said first and second signals (i1, i2),
- subtracting means (7) for subtracting said first and second signals (i1, i2),
- a first output (OUT+) for outputting a first output signal (vo1) based on the output signal from said adding means (6), and
- a second output (OUT−) for outputting a second output signal (vo2) based on the output signal from said subtracting means (7), characterized by at least:
- a first transistor with its collector connected to its base and its emitter coupled to a predetermined potential,
- a second transistor with its base connected to the base of said first transistor and its emitter coupled to said predetermined potential,
- a third transistor with its collector connected to its base and its emitter coupled to a predetermined potential,
- a fourth transistor with its base connected to the base of said third transistor and its collector coupled to said predetermined potential, and
- a capacitor (2c) coupled between a first junction of the bases of said first and second transistors and a second junction of the bases of said third and fourth transistors.
Dependencies are inferred from the claim text.