SAW-LESS RECEIVER INCLUDING AN IF FREQUENCY TRANSLATED BPF

• US 20140016729A1
• Filed: 09/16/2013
• Published: 01/16/2014
• Est. Priority Date: 06/03/2010
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Darabi, Hooman, Mirzaei, Ahmad
• Granted Patent: US 9,002,295 B2
• Time in Patent Office: Days
• US Class Current: 375/340
• CPC Class Codes: H03H 19/002 N-path filters
• CPC Class Codes: H04L 27/06 Demodulator circuits; Receiver circuits
• CPC Class Codes: H04L 27/34 Amplitude- and phase-modulated carrier systems, e.g. quadrature-amplitude modulated carrier systems

Abstract

A SAW-less receiver includes an FEM interface module, an RF to IF receiver section, and a receiver IF to baseband section. The RF to IF receiver section includes a mixing module, a mixed buffer section, and a frequency translated BPF (FTBPF) circuit module. The mixing module converts an inbound RF signal into an in-phase (I) mixed signal and a quadrature (Q) mixed signal. The mixed buffer section filters and buffers the I mixed signal and filter and buffer the Q mixed signal. The FTBPF circuit module frequency translates a baseband filter response to an IF filter response such that the FTBPF circuit module filters undesired signal components of the IF I signal and the IF Q signal to produce an inbound IF signal. The receiver IF to baseband section converts the inbound IF signal into one or more inbound symbol streams.

Claims

1. A surface acoustic wave (SAW)-less transceiver comprising:

a front end module (FEM) interface module configured to receive an inbound radio frequency (RF) signal;

an RF to intermediate frequency (IF) receiver section configured to;

down-convert the inbound RF signal into an inbound IF signal;

up-convert a baseband filter response to an IF filter response; and

filter the inbound IF signal based on the IF filter response to produce a filtered inbound IF signal; and

a receiver IF to baseband section configured to convert the filtered inbound IF signal into one or more inbound symbol streams.

2. The SAW-less transceiver of claim 1, wherein the FEM interface module comprises:

a transformer configured to receive an RF signal to produce a received RF signal;

a tunable capacitor network configured to filter the received RF signal to produce a filtered RF signal; and

a low noise amplifier module (LNA) configured to amplify the filtered RF signal to produce the inbound RF signal.

3. The SAW-less transceiver of claim 1, wherein the RF to IF receiver section down-converts the inbound RF signal into the inbound IF signal by:

converting the inbound RF signal into an in-phase (I) signal component and a quadrature (Q) signal component;

mixing the I signal component with an I signal component of a local oscillation to produce an I mixed signal; and

mixing the Q signal component with a Q signal component of the local oscillation to produce a Q mixed signal; and

filtering the I and Q mixed signals to produce the inbound IF signal.

4. The SAW-less transceiver of claim 3, wherein the RF to IF receiver section is configured to filter the I and Q mixed signals by:

attenuating a frequency sum component of the I mixed signal and passing a frequency difference component of the I mixed signal as an IF I signal component of the inbound IF signal; and

attenuating a frequency sum component of the Q mixed signal and passing a frequency difference component of the Q mixed signal as an IF Q signal component of the inbound IF signal.

5. The SAW-less transceiver of claim 1, wherein the RF to IF receiver section down-converting the inbound RF signal into the inbound IF signal further comprising:

attenuating an undesired signal component of an IF I signal of the inbound IF signal; and

attenuating an undesired signal component of an IF Q signal of the inbound IF signal.

6. The SAW-less transceiver of claim 1, further comprising a front end module configured to isolate the inbound RF signal from an undesired RF signal.

7. The SAW-less transceiver of claim 1, wherein the RF to IF receiver section is configured to up-convert the baseband filter response by:

utilizing a first baseband filter response to filter the inbound IF signal during a first clock interval of an IF clock;

utilizing a second baseband filter response to filter the inbound IF signal during a second clock interval of the IF clock;

utilizing an inverse first baseband filter response to filter the inbound IF signal during a third clock interval of the IF clock; and

utilizing an inverse second baseband filter response to filter the inbound IF signal during a fourth clock interval of the IF clock.

8. The SAW-less transceiver of claim 1, wherein the RF to IF receiver section is configured to up-convert the baseband filter response by:

receiving a control signal; and

based on the control signal, adjusting one or more of;

a center frequency of the baseband filter response, a quality factor of the baseband filter response, a gain of the baseband filter response, a bandwidth of the baseband filter response, and an attenuation slope of the baseband filter response.

9. A method of operating a surface acoustic wave (SAW)-less transceiver comprising:

receiving an inbound radio frequency (RF) signal;

down-converting the inbound RF signal into an inbound IF signal;

up-converting a baseband filter response to an IF filter response; and

filtering the inbound IF signal based on the IF filter response to produce a filtered inbound IF signal; and

converting the filtered inbound IF signal into one or more inbound symbol streams.

10. The method of claim 9, further comprising:

receiving an RF signal;

filtering the received RF signal to produce a filtered RF signal; and

amplifying the filtered RF signal to produce the inbound RF signal.

11. The method of claim 9, wherein down-converting the inbound RF signal into an inbound IF signal comprises:

converting the inbound RF signal into an in-phase (I) signal component and a quadrature (Q) signal component;

mixing the I signal component with an I signal component of a local oscillation to produce an I mixed signal; and

mixing the Q signal component with a Q signal component of the local oscillation to produce a Q mixed signal; and

filtering the I and Q mixed signals to produce the inbound IF signal.

12. The method of claim 11, wherein filtering the I and Q mixed signals comprises:

attenuating a frequency sum component of the I mixed signal and passing a frequency difference component of the I mixed signal as an IF I signal component of the inbound IF signal; and

attenuating a frequency sum component of the Q mixed signal and passing a frequency difference component of the Q mixed signal as an IF Q signal component of the inbound IF signal.

13. The method of claim 9, wherein down-converting the inbound RF signal into the inbound IF signal further comprises:

attenuating an undesired signal component of an IF I signal of the inbound IF signal; and

attenuating an undesired signal component of an IF Q signal of the inbound IF signal.

14. The method of claim 9, further comprising isolating the inbound RF signal from an undesired RF signal.

15. The method of claim 9, further comprising up-converting the baseband filter response by:

utilizing a first baseband filter response to filter the inbound IF signal during a first clock interval of an IF clock;

utilizing a second baseband filter response to filter the inbound IF signal during a second clock interval of the IF clock;

utilizing an inverse first baseband filter response to filter the inbound IF signal during a third clock interval of the IF clock; and

utilizing an inverse second baseband filter response to filter the inbound IF signal during a fourth clock interval of the IF clock.

16. The method of claim 9, wherein up-converting the baseband filter response comprises:

receiving a control signal; and

based on the control signal, adjusting one or more of;

a center frequency of the baseband filter response, a quality factor of the baseband filter response, a gain of the baseband filter response, a bandwidth of the baseband filter response, and an attenuation slope of the baseband filter response.

17. A surface acoustic wave (SAW)-less transceiver comprising:

a transmitter section; and

a receiver section comprising;

a front end module (FEM) interface module configured to receive an inbound radio frequency (RF) signal;

an RF to intermediate frequency (IF) receiver section configured to;

down-convert the inbound RF signal into an inbound IF signal;

up-convert a baseband filter response to an IF filter response; and

filter the inbound IF signal based on the IF filter response to produce a filtered inbound IF signal; and

a receiver IF to baseband section configured to convert the filtered inbound IF signal into one or more inbound symbol streams.

18. The SAW-less transceiver of claim 17, wherein the FEM interface module comprises:

a transformer configured to receive an RF signal to produce a received RF signal;

a tunable capacitor network configured to filter the received RF signal to produce a filtered RF signal; and

a low noise amplifier module (LNA) configured to amplify the filtered RF signal to produce the inbound RF signal.

19. The SAW-less transceiver of claim 17, wherein the RF to IF receiver section is configured to up-convert the baseband filter response by:

utilizing a first baseband filter response to filter the inbound IF signal during a first clock interval of an IF clock;

utilizing a second baseband filter response to filter the inbound IF signal during a second clock interval of the IF clock;

utilizing an inverse first baseband filter response to filter the inbound IF signal during a third clock interval of the IF clock; and

utilizing an inverse second baseband filter response to filter the inbound IF signal during a fourth clock interval of the IF clock.

20. The SAW-less transceiver of claim 17, wherein the RF to IF receiver section is configured to up-convert the baseband filter response by:

receiving a control signal; and

based on the control signal, adjusting one or more of;

a center frequency of the baseband filter response, a quality factor of the baseband filter response, a gain of the baseband filter response, a bandwidth of the baseband filter response, and an attenuation slope of the baseband filter response.