Transformer feed-back quadrature voltage controlled oscillator for correcting dynamic phase error and communication apparatus using the same
AssigneeNational Chung Shan Institute of Science and Technology
InventorsHSIAO-CHIN CHEN, YEN-TING CHIANG, CHIEN-TE YU
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Abstract
A transformer feed-back quadrature voltage controlled oscillator (QVCO) includes a first VCO; a second VCO; and a dynamic phase error correction circuit, having a plurality of coupling capacitors connected between the first and second VCOs, wherein the capacitances of the coupling capacitors are varied according to a digital control signal to correct a phase error of local oscillating (LO) signals of quadrature phases output by the first and second VCOs.
Claims19
A transformer feed-back quadrature voltage controlled oscillator (QVCO), comprising:
- a first VCO;
- a second VCO;
- and
- a dynamic phase error correction circuit, having a plurality of coupling capacitors connected between the first and second VCOs, wherein the capacitances of the coupling capacitors are varied according to a digital control signal to correct a phase error of local oscillating (LO) signals of quadrature phases output by the first and second VCOs.
A communication apparatus, comprising:
- a transformer feed-back QVCO;
- a front-end circuit, connected to the transformer feed-back QVCO;
- wherein the transformer feed-back QVCO comprises:
- a first VCO;
- a second VCO;
- and
- a dynamic phase error correction circuit, having a plurality of coupling capacitors connected between the first and second VCOs, wherein the capacitances of the coupling capacitors are varied according to a digital control signal to correct a phase error of local oscillating (LO) signals of quadrature phases output by the first and second VCOs.
Dependencies are inferred from the claim text.