Method and system for configurable active/passive mixer and shared GM stage

• US 8,081,947 B2
• Filed: 12/31/2006
• Issued: 12/20/2011
• Est. Priority Date: 12/06/2006
• Status: Expired due to Fees

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Ojo, Adedayo, Hafizi, Madjid, Behzad, Arya
• Primary Examiner(s): Nguyen, Simon
• Application Number:
  US11/618,853
• Publication Number:
  US 20080139159A1
• Time in Patent Office: 1,815 Days
• Field of Search: 455312-319, 455323-326, 455/333
• US Class Current: 455/313
• CPC Class Codes: H03D 2200/0084 Lowering the supply voltage and saving power
• CPC Class Codes: H03D 2200/009 Reduction of local oscillator or RF leakage
• CPC Class Codes: H03D 7/1441 using field-effect transistors H03D7/145 takes precedence
• CPC Class Codes: H03D 7/1458 Double balanced arrangements, i.e. where both input signals are differential
• CPC Class Codes: H03D 7/1466 Passive mixer arrangements
• CPC Class Codes: H03D 7/165 at least two frequency changers being located in different paths, e.g. in two paths with carriers in quadrature combined with amplitude demodulation H03D1/2245, combined with angle demodulation H03D3/007; N-path filters H03H19/002
• CPC Class Codes: H03D 7/166 using two or more quadrature frequency translation stages
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Aspects of a method and system for configurable Active/Passive Mixer and Shared GM Stage may include configuring an RF mixer in frequency demodulator to operate in an active mode or a passive mode. An in-phase (I) processing path and a quadrature (Q) processing path of the RF mixer may utilize a single shared GM stage. One or more switches may be activated to enable the active mode or the passive mode of operation for the RF mixer.

Claims

1. A method for processing signals in a communications system the method comprising:

configuring, by a processor in a wireless communication device, an RF mixer in a frequency demodulator to operate in an active mode or a passive mode, said RF mixer comprising separate in-phase and quadrature mixer stages; and

sharing a single transconductance stage by said separate in-phase and quadrature mixer stages of said RF mixer, wherein said active mode is configured by selectively coupling a common-mode feedback block to outputs of each of said separate in-phase and quadrature mixer stages and selectively coupling an active load between said single shared transconductance stage and said separate in-phase and quadrature mixer stages.

2. The method according to claim 1, comprising converting said in-phase and quadrature mixer stages of said RF mixer in said frequency demodulator from a passive configuration to an active configuration.

3. The method according to claim 1, comprising activating one or more switches to enable said active mode or said passive mode of operation for said RF mixer.

4. The method according to claim 1, comprising processing wideband modulated signals when said frequency demodulator is configured to operate in said active mode.

5. The method according to claim 1, comprising processing narrowband modulated signals when said frequency demodulator is configured to operate in said passive mode.

6. A system for processing signals in a communications system, the system comprising:

one or more circuits that configures an RF mixer in a frequency demodulator to operate in an active mode or a passive mode, said RF mixer comprising separate in-phase and quadrature mixer stages; and

a single transconductance stage that is shared by said in-phase and said quadrature mixer stages of said RF mixer, wherein said active mode is configured by selectively coupling a common-mode feedback block to outputs of each of said separate in-phase and quadrature mixer stages and selectively coupling an active load between said single shared transconductance stage and said separate in-phase and quadrature mixer stages.

7. The system according to claim 6, wherein said one or more circuits enables conversion of said in-phase and quadrature mixer stages of said RF mixer in said frequency demodulator from a passive configuration to an active configuration.

8. The system according to claim 6, wherein said one or more circuits activates one or more switches to enable said active mode or said passive mode of operation for said RF mixer.

9. The system according to claim 6, comprising processing wideband modulated signals when said frequency demodulator is configured to operate in said active mode.

10. The system according to claim 6, comprising processing narrowband modulated signals when said frequency demodulator is configured to operate in said passive mode.