Adjustable circuit architecture

• US 8,862,088 B2
• Filed: 09/22/2009
• Issued: 10/14/2014
• Est. Priority Date: 09/22/2009
• Status: Active Grant

• Current Assignee: WSOU Investments, LLC (WSOU Holdings, LLC)
• Original Assignee: Nokia Corporation
• Inventors: Ryynanen, Jussi, Kaltiokallio, Mikko
• Primary Examiner(s): Trinh, Sonny
• Application Number:
  US13/497,485
• Publication Number:
  US 20120178391A1
• Time in Patent Office: 1,848 Days
• Field of Search: 455/306, 455/307, 455/313, 455/341, 455/194.2, 455/339
• US Class Current: 455/307
• CPC Class Codes: H03F 1/3211 in differential amplifiers
• CPC Class Codes: H03F 1/3241 using predistortion circuits H03F1/3211, H03F1/3217 take precedence
• CPC Class Codes: H03F 1/34 Negative-feedback-circuit arrangements with or without positive feedback H03F1/02 - H03F1/30, H03F1/38 - H03F1/50, H03F3/50 take precedence ; for rejection of common mode signals H03F3/45479
• CPC Class Codes: H03F 2200/165 A filter circuit coupled to the input of an amplifier
• CPC Class Codes: H03F 2200/168 Two amplifying stages are coupled by means of a filter circuit
• CPC Class Codes: H03F 2200/171 A filter circuit coupled to the output of an amplifier
• CPC Class Codes: H03F 2200/294 the amplifier being a low noise amplifier [LNA]
• CPC Class Codes: H03F 2200/411 the output amplifying stage of an amplifier comprising two power stages
• CPC Class Codes: H03F 2203/45511 the feedback circuit [FBC] comprising one or more transistor stages, e.g. cascaded stages of the dif amp, and being coupled between the loading circuit [LC] and the input circuit [IC]
• CPC Class Codes: H03F 2203/45512 the FBC comprising one or more capacitors, not being switched capacitors, and being coupled between the LC and the IC
• CPC Class Codes: H03F 2203/45522 the FBC comprising one or more potentiometers
• CPC Class Codes: H03F 2203/45528 the FBC comprising one or more passive resistors and being coupled between the LC and the IC
• CPC Class Codes: H03F 2203/45544 the IC comprising one or more capacitors, e.g. coupling capacitors
• CPC Class Codes: H03F 2203/45631 the LC comprising one or more capacitors, e.g. coupling capacitors
• CPC Class Codes: H03F 2203/45638 the LC comprising one or more coils
• CPC Class Codes: H03F 2203/45702 the LC comprising two resistors
• CPC Class Codes: H03F 3/19 with semiconductor devices only
• CPC Class Codes: H03F 3/191 Tuned amplifiers H03F3/193, H03F3/195 take precedence
• CPC Class Codes: H03F 3/45179 using MOSFET transistors as the active amplifying circuit H03F3/45278 takes precedence
• CPC Class Codes: H03F 3/45183 Long tailed pairs H03F3/4521, H03F3/45237 take precedence

Abstract

An amplifier circuitry having adjustable parameters is presented. The present amplifier circuitry includes a feed-back loop, wherein the feedback loop converts (26) a signal to another frequency, filters (20) the signal in the other frequency, and restores (24) the filtered signal back to the original frequency for inputting the signal to an input of the amplifier (22). The feed-back loop implements a band-stop filter (20) having an adjustable stopband causing the amplifier circuitry to have an adjustable band-pass response. A passband of the amplifier circuitry is changed from one operating frequency to another operating frequency by changing frequency conversion parameters of the feedback loop.

Claims

1. An apparatus comprising an amplifier with a feedback loop circuitry, wherein the feedback loop circuitry comprises:

a first frequency converter circuitry configured to frequency-convert a signal input to the feedback loop circuitry from a first frequency to a second frequency by using a first local oscillator signal;

a filter circuitry configured to modify the frequency-converted signal on the second frequency; and

a second frequency converter circuitry configured to frequency-convert the modified signal from the second frequency back to the first frequency by using a second local oscillator signal and to output the frequency-converted and modified signal to be applied to an input of the amplifier,

wherein the feedback loop circuitry implements a band-stop filter having an adjustable stopband causing the amplifier to have an adjustable band-pass response, and wherein a passband of the amplifier is changed from one operating frequency to another operating frequency by changing frequency conversion parameters of the first frequency converter circuitry and the second frequency converter circuitry.

2. The apparatus of claim 1, wherein the filter circuitry comprises a polyphase filter having an adjustable phase shift in order to achieve different phase shifts for a plurality of different operating frequencies supported by the apparatus.

3. The apparatus of claim 1, wherein the first frequency converter circuitry is a down-converter circuitry configured to down-convert the signal from a higher frequency to a lower frequency and to output the down-converted signal to the filter circuitry, wherein the filter circuitry is configured to modify the signal received from the down-converter circuitry on the lower frequency, and wherein the second frequency converter circuitry is an up-converter circuitry configured to up-convert an output signal of the filter circuitry from the lower frequency to the higher frequency and to apply the up-converted band-stop signal to the input of the amplifier.

4. The apparatus of claim 3, wherein the lower frequency is baseband and wherein the filter circuitry is configured to high-pass filter and phase-adjust the signal received from the down-converter circuitry on the baseband.

5. The apparatus of claim 3, wherein the amplifier circuitry is configured to change a passband frequency through a change in a frequency of a local oscillator signal applied to the down-converter circuitry and the up-converter circuitry.

6. The apparatus of claim 1, wherein the feedback loop circuitry is selectively disconnectable from the amplifier when an interference environment is determined to be below a preset threshold level.

7. The apparatus of claim 1, wherein the feedback loop circuitry is inherently passive in terms of amplification of the signal applied to the feedback loop circuitry.

8. The apparatus of claim 1, wherein the apparatus is applicable to a radio communication device and further comprises a controller configured to change a circuit configuration of the feedback loop circuitry in response to a change in an operating frequency of the radio communication device.

9. The apparatus of claim 8, wherein the controller is further configured to change a frequency of a local oscillator signal of the up-converter circuitry and the down-converter circuitry and to change the phase configuration of the polyphase filter in response to the change in the operating frequency of the radio communication device.

10. The apparatus of claim 8, wherein the controller is further configured to disconnect the feedback loop circuitry from the amplifier when an interference environment is determined to be below a preset threshold level.

11. The apparatus of claim 1, wherein the apparatus is a radio communication device further comprising a controller configured to control the operation of the radio communication device and a memory unit including computer program code configuring the operation of the controller.

12. A method, comprising:

providing an amplifier circuitry comprising an amplifier with a feedback loop circuitry, the feedback loop circuitry comprising a first frequency converter circuitry, a filter circuitry, and a second frequency converter circuitry, wherein the feedback loop circuitry implements a band-stop filter having an adjustable stopband causing the amplifier circuitry to have an adjustable band-pass response;

frequency-converting, in the first frequency converter circuitry comprised in the feedback loop circuitry, a signal input to the feedback loop circuitry from a first frequency to a second frequency by using a first local oscillator signal;

modifying the frequency-converted signal on the second frequency in the filter circuitry;

frequency-converting, in the second frequency converter circuitry, the modified signal from the second frequency back to the first frequency by using a second local oscillator signal;

inputting the frequency-converted and modified signal to an input of the amplifier; and

changing a passband of the amplifier circuitry from one operating frequency to another operating frequency by changing frequency conversion parameters of the first frequency converter circuitry and the second frequency converter circuitry.

13. The method of claim 12, further comprising:

selecting, on the basis of a current operating frequency, a circuit configuration for a polyphase filter comprised in the filter circuitry in order to achieve desired phase shift properties among a plurality of different phase shifts associated with a plurality of supported operating frequencies; and

configuring the polyphase filter to apply the selected circuit configuration in order to achieve the desired phase shift for the current operating frequency.

14. The method of claim 12, wherein the first frequency converter circuitry is a down-converter circuitry and the second frequency converter circuitry is an up-converter circuitry, the method further comprising:

down-converting, in the down-converter circuitry, a signal applied to an input of the feedback loop circuitry from a radio frequency to a lower frequency;

modifying, in the filter circuitry, the down-converted signal received from the down-converter on the lower frequency; and

up-converting, in the up-converter circuitry, the filtered and phase-compensated signal from the lower frequency to the higher frequency, and applying the up-converted band-stop signal to the input of the amplifier.

15. The method of claim 14, wherein the lower frequency is baseband, wherein the filtering is carried out as high-pass filtering, and wherein the high-pass filtering and phase-adjustment are carried out on the baseband.

16. The method of claim 14, further comprising:

changing the passband frequency of the amplifier circuitry by changing a frequency of a local oscillator signal applied to the down-converter circuitry and the up-converter circuitry.

17. The method of claim 12, further comprising:

disconnecting the feedback loop circuitry from the amplifier or connecting the feedback loop circuitry to the amplifier on the basis of an interference environment determined to be below a preset threshold level.

18. The method of claim 12, wherein the amplifier circuitry is applied to a radio communication device and wherein the method further comprises changing a circuit configuration of the feedback loop circuitry in response to a change in an operating frequency of the radio communication device.

19. A method comprising:

selecting, on the basis of an operating frequency to be applied, a circuit configuration for a feedback loop circuitry of an amplifier circuitry comprising an amplifier with the feedback loop circuitry, the feedback loop circuitry comprising a first frequency converter circuitry configured to frequency-convert a signal input to the feedback loop circuitry from a first frequency to a second frequency by using a first local oscillator signal;

a filter circuitry configured to modify the frequency-converted signal on the second frequency; and

a second frequency converter circuitry configured to frequency-convert the modified signal from the second frequency back to the first frequency by using a second local oscillator signal and to output the frequency-converted and modified signal to be applied to an input of the amplifier, wherein the feedback loop circuitry implements a band-stop filter having an adjustable stopband causing the amplifier circuitry to have an adjustable band-pass response, and wherein a passband of the amplifier circuitry is changed from one operating frequency to another operating frequency by changing frequency conversion parameters of the first frequency converter circuitry and the second frequency converter circuitry; and

configuring the first frequency converter circuitry and the second frequency converter circuitry to apply the selected circuit configuration and to have frequency conversion parameters associated with the operating frequency to be applied.

20. An apparatus comprising a controller circuitry configured to:

select, on the basis of an operating frequency to be applied, a circuit configuration for a feedback loop circuitry of an amplifier circuitry comprising an amplifier with the feedback loop circuitry, the feedback loop circuitry comprising a first frequency converter circuitry configured to frequency-convert a signal input to the feedback loop circuitry from a first frequency to a second frequency by using a first local oscillator signal;

a filter circuitry configured to modify the frequency-converted signal on the second frequency; and

a second frequency converter circuitry configured to frequency-convert the modified signal from the second frequency back to the first frequency by using a second local oscillator signal and to output the frequency-converted and modified signal to be applied to an input of the amplifier, wherein the feedback loop circuitry implements a band-stop filter having an adjustable stopband causing the amplifier circuitry to have an adjustable band-pass response, and wherein a passband of the amplifier circuitry is changed from one operating frequency to another operating frequency by changing frequency conversion parameters of the first frequency converter circuitry and the second frequency converter circuitry; and

configure the first frequency converter circuitry and the second frequency converter circuitry to apply the selected circuit configuration and to have frequency conversion parameters associated with the operating frequency to be applied.