Quadrature signal generation in radio-frequency apparatus and associated methods

• US 8,532,236 B2
• Filed: 10/15/2009
• Issued: 09/10/2013
• Est. Priority Date: 01/12/2001
• Status: Expired due to Fees

• Current Assignee: Silicon Laboratories Incorporated
• Original Assignee: Silicon Laboratories Incorporated
• Inventors: Kerth, Donald A.
• Primary Examiner(s): Ahn, Sam K
• Assistant Examiner(s): Vlahos, Sophia
• Application Number:
  US12/579,591
• Publication Number:
  US 20100167684A1
• Time in Patent Office: 1,426 Days
• Field of Search: 375/136, 375/147, 375/316, 375/219, 375/346, 375/306, 375/307, 375/349, 375/350, 455/334, 455339-340, 455/76, 455/146, 455/147, 455208-209, 455/255, 455/258, 455/259, 455/260, 455313-317, 455/552.1, 455/77, 455/86, 455/88, 455/114.2, 455/141, 455/165.1, 455/196.1, 331/45
• US Class Current: 375/346
• CPC Class Codes: H04B 1/0003 Software-defined radio [SDR] systems, i.e. systems wherein components typically implemented in hardware, e.g. filters or modulators/demodulators, are implented using software, e.g. by involving an AD or DA conversion stage such that at least part of the signal processing is performed in the digital domain digital baseband systems H04L25/00; digital modulation/demodulation H04L27/00; CDMA H04B1/707; TDMA H04B7/2643; image transmission H04N5/00
• CPC Class Codes: H04B 1/28 the receiver comprising at least one semiconductor device having three or more electrodes
• CPC Class Codes: H04B 1/406 with more than one transmission mode, e.g. analog and digital modes
• CPC Class Codes: H04B 15/02 Reducing interference from electric apparatus by means located at or near the interfering apparatus
• CPC Class Codes: H04B 15/04 the interference being caused by substantially sinusoidal oscillations, e.g. in a receiver or in a tape-recorder
• CPC Class Codes: H04B 2215/064 Reduction of clock or synthesizer reference frequency harmonics

Abstract

A radio-frequency (RF) apparatus, which may reside in a receiver or transceiver, includes receive-path circuitry. The receive-path circuitry includes a poly-phase filter and a harmonic filter. The poly-phase filter accepts an input signal and generates two output signals. One output signal of the poly-phase filter constitutes an in-phase (I) signal. The other output signal of the poly-phase filter constitutes a quadrature (Q) signal. The a harmonic filter couples to the poly-phase filter. The harmonic filter accepts as input signals the in-phase and quadrature output signals of the poly-phase filter.

Claims

1. A radio-frequency (RF) apparatus, comprising:

a first circuit partition, comprising;

down-converter circuitry adapted to receive a radio-frequency (RF) signal and to mix the RF signal with a complex local oscillator signal to generate a complex analog signal;

an analog-to-digital converter (ADC) adapted to receive the complex analog signal and to generate a complex digital signal; and

an interface circuit adapted to receive the complex digital signal and to generate a complex output signal having a one-bit in-phase component and a one-bit quadrature component, wherein the complex output signal is coupled to a digital down-converter circuitry, having in-phase and quadrature outputs, which is coupled to a digital filter circuitry, having in-phase and quadrature outputs, which is coupled to a digital-to-analog (DAC) circuitry; and

a second circuit partition, comprising;

a poly-phase filter adapted to accept an input signal and provide a first in-phase signal and a first quadrature signal; and

a harmonic filter coupled to the poly-phase filter, the harmonic filter adapted to accept the first in-phase signal and the first quadrature signal and to generate the complex local oscillator signal.

2. The radio-frequency (RF) apparatus according to claim 1, wherein the first circuit partition comprises a first integrated circuit (IC).

3. The radio-frequency (RF) apparatus according to claim 1, wherein the second circuit partition comprises a second integrated circuit (IC).

4. The radio-frequency (RF) apparatus according to claim 1, wherein the first and second circuit partitions reside within a module.

5. The radio-frequency (RF) apparatus according to claim 1, wherein the one-bit in-phase component comprises a differential signal.

6. The radio-frequency (RF) apparatus according to claim 1, wherein the one-bit quadrature component comprises a differential signal.

7. The radio-frequency (RF) apparatus according to claim 1, wherein the first circuit partition comprises a low intermediate-frequency (IF) receiver.

8. The radio-frequency (RF) apparatus according to claim 1, wherein the first circuit partition comprises a direct conversion receiver.

9. A radio-frequency (RF) apparatus, comprising:

a first circuit partition, comprising;

up-converter circuitry adapted to receive a complex signal and to mix the complex signal with a first local oscillator signal to generate an output signal;

a mixer adapted to mix a first input signal with a second local oscillator signal to generate a mixed signal, wherein the first input signal is derived in part by filtering an output signal of a phase detection circuitry; and

a second circuit partition, comprising;

a poly-phase filter adapted to accept a second input signal and provide a first in-phase signal and a first quadrature signal; and

a harmonic filter coupled to the poly-phase filter, the harmonic filter adapted to accept the first in-phase signal and the first quadrature signal and to generate the second local oscillator signal,

wherein the output signal is coupled to a first input of the phase detection circuitry, and wherein the mixed signal is coupled to a second input of the phase detection circuitry.

10. The radio-frequency (RF) apparatus according to claim 9, wherein the first circuit partition comprises a first integrated circuit (IC).

11. The radio-frequency (RF) apparatus according to claim 9, wherein the second circuit partition comprises a second integrated circuit (IC).

12. The radio-frequency (RF) apparatus according to claim 9, wherein the first and second circuit partitions reside within a module.

13. The radio-frequency (RF) apparatus according to claim 9, wherein the first local oscillator signal comprises a differential signal.

14. The radio-frequency (RF) apparatus according to claim 9, wherein the second local oscillator signal comprises a differential signal.

15. The radio-frequency (RF) apparatus according to claim 9, wherein an output of the phase detection circuitry is coupled to an oscillator.