Multi-Standard Transceiver Architecture with Common Balun and Mixer

• US 20130116005A1
• Filed: 05/04/2012
• Published: 05/09/2013
• Est. Priority Date: 05/12/2011
• Status: Active Grant

• Current Assignee: ST-Ericcson SA (Telefonaktiebolaget LM Ericsson)
• Original Assignee: ST-Ericcson SA (Telefonaktiebolaget LM Ericsson)
• Inventors: Ganti, Ramkishore, Ranganathan, Sanjeev, Sridharan, Srinath
• Granted Patent: US 8,892,159 B2
• Time in Patent Office: Days
• US Class Current: 455/552.1
• CPC Class Codes: H04B 1/0053 with common antenna for more than one band
• CPC Class Codes: H04B 1/0458 Arrangements for matching and coupling between power amplifier and antenna or between amplifying stages matching circuits in general H03H
• CPC Class Codes: H04B 1/0483 Transmitters with multiple parallel paths
• CPC Class Codes: H04B 1/406 with more than one transmission mode, e.g. analog and digital modes
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

A multi-standard transceiver comprises a common balun, a controller, at least one first switch, and at least one second switch. The common balun comprises a primary coil and a secondary coil. The at least one first switch connects the primary coil of the balun to a first signal path associated with a first communication standard, or to a second signal path associated with a second communication standard responsive to a control signal provided by the controller. The at least one second switch connects the secondary coil of the balun to a first amplification path associated with the first communication standard, or to a second amplification path associated with the second communication standard responsive to a control signal provided by the controller. A common mixer is configured to provide upconverted signals to one of the signal paths depending on which communication standard has been selected.

Claims

1. A multi-standard transceiver operative to transmit signals using either a first communication standard or a different second communication standard, the transceiver comprising:

a balun comprising a primary coil and a secondary coil;

a controller configured to control which communication standard is used by the multi-standard transceiver for signal transmissions;

at least one first switch operative to connect the primary coil of the balun to a first signal path associated with the first communication standard or a second signal path associated with the second communication standard responsive to a control signal provided by the controller;

at least one second switch operative to connect the secondary coil of the balun to a first amplification path associated with the first communication standard or a second amplification path associated with the second communication standard responsive to a control signal provided by the controller; and

a mixer configured to;

output upconverted signals associated with the first communication standard to the first signal path responsive to a control signal output by the controller when the multi-standard transceiver operates according to the first communication standard; and

output upconverted signals associated with the second communication standard to the second signal path responsive to a control signal output by the controller when the multi-standard transceiver operates according to the second communication standard.

2. The multi-standard transceiver of claim 1, wherein the first and second communication standards are wireless communication standards, and wherein the multi-standard transceiver further comprises a radio frequency (RF) buffer connecting the common mixer to the primary coil of the balun along one of the first signal path or the second signal path.

3. The multi-standard transceiver of claim 1, wherein the common mixer comprises at least one Gilbert cell mixer.

4. The multi-standard transceiver of claim 1, wherein the at least one second switch includes a first output switch and a second output switch, the multi-standard transceiver further comprising a post-balun output circuit that includes:

a first line coupling a first end of the secondary coil of the balun to the first amplification path via a first output pad;

a second line coupling an opposite second end of the secondary coil of the balun to the second amplification path via a second output pad; and

a third line operative to selectively couple outputs of the first and second output switches to ground via a third output pad responsive to a state of the first and second output switches.

5. The multi-standard transceiver of claim 4, further comprising a plurality of biasing resistors connected to the third line, the biasing resistors being configured to bias a DC voltage of the first, second and third output pads away from ground.

6. The multi-standard transceiver of claim 4, further comprising a decoupling capacitor connected to the third line between the outputs of the first and second output switches and the third output pad to reduce a resonance of an output bond wire connected to the third output pad.

7. A method of operating a transceiver to use either a first communication standard or a different second communication standard, the transceiver comprising a common mixer and a common balun that are utilized in signal processing operations for both of the communication standards, the method comprising:

outputting, via the common mixer, upconverted signals associated with a selected one of the communication standards;

controlling at least one first switch to selectively connect a primary coil of the balun to the upconverted signals via either a first signal path corresponding to the first communication standard, or a second signal path corresponding to the second communication standard, responsive to the communication standard selection; and

controlling at least one second switch to connect a secondary coil of the balun to either a first amplification path associated with the first communication standard or a second amplification path associated with the second communication standard, responsive to the communication standard selection.

8. The method of claim 7, wherein the first and second communication standards are wireless communication standards, and wherein the multi-standard transceiver further comprises a radio frequency (RF) buffer connecting the common mixer to the primary coil of the balun along one of the first signal path or the second signal path.

9. The method of claim 7, wherein the common mixer comprises at least one Gilbert cell mixer.

10. The method of claim 7, wherein the at least one second switch includes a first output switch and a second output switch, and the multi-standard transceiver further comprises a post-balun output circuit that includes a first line coupling a first end of the secondary coil of the balun to the first amplification path via a first output pad, a second line coupling an opposite second end of the secondary coil of the balun to the second amplification path via a second output pad, and a third line operative to selectively couple outputs of the first and second output switches to ground via a third output pad, the method further comprising:

biasing a DC voltage of the first, second and third output pads away from ground via a plurality of biasing resistors connected to the third line.

11. The method of claim 10, further comprising:

reducing a resonance of an output bond wire connected to the third output pad via a decoupling capacitor connected to the third line between the outputs of the first and second output switches and the third output pad.