BLUETOOTH AND WLAN COEXISTENCE ARCHITECTURE HAVING A SHARED LOW NOISE AMPLIFIER

• US 20090239471A1
• Filed: 03/17/2009
• Published: 09/24/2009
• Est. Priority Date: 03/18/2008
• Status: Active Grant

• Current Assignee: Marvell Asia Pte Limited (Marvell Technology Group Limited)
• Original Assignee: Marvell World Trade Limited (Marvell Technology Group Limited)
• Inventors: Lee, George, Tokubo, Todd, Wong, Gladys Yuen Yan, Li, Timothy, Yeung, Ken, Tran, Ninh, Chokshi, Ronak Anjan
• Granted Patent: US 8,165,544 B2
• Time in Patent Office: Days
• US Class Current: 455/41.200
• CPC Class Codes: H04B 1/006 using switches for selecting the desired band H04B1/0057 takes precedence
• CPC Class Codes: H04B 1/406 with more than one transmission mode, e.g. analog and digital modes
• CPC Class Codes: H04B 1/48 in circuits for connecting transmitter and receiver to a common transmission path, e.g. by energy of transmitter H04B1/46 takes precedence
• CPC Class Codes: H04W 52/287 when the channel is in stand-by
• 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 radio frequency (RF) front-end configured to share transmissions and receptions of Bluetooth signals and WLAN signals. In an exemplary embodiment, the RF front-end comprises a first path coupled between an antenna and a transceiver dedicated to transmissions of the WLAN signals; a second path coupled between the antenna and the transceiver dedicated to simultaneous receptions of the Bluetooth signals and the WLAN signals; and a third path coupled between the antenna and the transceiver. The third path may be dedicated to transmissions only of the Bluetooth signals when a WLAN link is active; and transmissions and receptions of the Bluetooth signals when the WLAN link is active and in a power save state, and when the WLAN link is inactive.

Claims

1. A radio frequency (RF) front-end configured to share transmissions and receptions of Bluetooth signals and WLAN signals, the RF front-end comprising:

a first path coupled between an antenna and a transceiver dedicated to transmissions of the WLAN signals;

a second path coupled between the antenna and the transceiver dedicated to simultaneous receptions of the Bluetooth signals and the WLAN signals; and

a third path coupled between the antenna and the transceiver dedicated to;

transmissions only of the Bluetooth signals when a WLAN link is active;

and

transmissions and receptions of the Bluetooth signals when the WLAN link is active and in a power save state, and when the WLAN link is inactive.

2. The system of claim 1 wherein the RF front-end further comprises a switch coupled between to the antenna and the first, second, and third paths to control which of the first, second, and third paths to connect to the antenna.

3. The system of claim 2 wherein the second path further comprises an amplifier coupled between the antenna and a divider, the divider having a WLAN receive output path and a Bluetooth receive output path coupled to the transceiver, wherein the amplifier is shared by the Bluetooth signals and the WLAN signals received from the antenna to amplify the Bluetooth signals and the WLAN signals to compensate for a loss of signal strength and outputs amplified Bluetooth and WLAN signals, and wherein the divider splits the amplified Bluetooth and WLAN signals onto a WLAN receive path and a Bluetooth receive path.

4. The method of claim 3 wherein the amplifier comprises a low noise amplifier.

5. The method of claim 3 wherein the WLAN receive path is coupled to the transceiver, and the Bluetooth receive path is coupled to an input to the third path for Bluetooth receptions.

6. The system of claim 3 wherein the amplifier receives an enable signal originating from the transceiver, such that the amplifier can be switched off to reduce current consumption of the RF front-end whenever the second path is not selected.

7. The system of claim 3 wherein the amplifier receives a bypass signal originating from the transceiver, wherein the bypass signal causes the Bluetooth signals and WLAN signals to pass through the amplifier without amplification when the second path is selected, but no gain is required.

8. The system of claim 3 wherein the second and third paths are multiplexed using another switch that selects the Bluetooth receive path output by the divider when the RF front-end is receiving the Bluetooth signals on the second path, and selects the third path when the RF front-end is transmitting the Bluetooth signals.

9. A method for providing a radio frequency (RF) front-end for sharing transmissions and receptions of Bluetooth signals and WLAN signals, the method comprising:

providing a first path coupled between an antenna and a transceiver dedicated to transmissions of the WLAN signals;

providing a second path coupled between the antenna and the transceiver dedicated to simultaneous receptions of the Bluetooth signals and the WLAN signals; and

providing a third path coupled between the antenna and the transceiver, the third path dedicated to;

transmissions only of the Bluetooth signals when a WLAN link is active; and

transmissions and receptions of the Bluetooth signals when the WLAN link is active, but in a power save state, and when the WLAN link is inactive.

10. The method of claim 9 further comprising providing a switch coupled between to the antenna and the first, second, and third paths to control which of the first, second, and third paths to connect to the antenna.

11. The method of claim 10 further comprising providing the second path with an amplifier coupled between the switch and a divider, wherein the amplifier is shared by the Bluetooth signals and the WLAN signals received from the antenna to amplify the Bluetooth signals and the WLAN signals to compensate for a loss of signal strength and outputs amplified Bluetooth and WLAN signals, and wherein the divider splits the amplified Bluetooth and WLAN signals onto a WLAN receive path and a Bluetooth receive path.

12. The method of claim 11 further comprising providing a low noise amplifier as the amplifier.

13. The method of claim 11 further comprising coupling the WLAN receive path to the transceiver, and coupling the Bluetooth receive path to an input to the third path for Bluetooth receptions.

14. The method of claim 11 further comprising inputting an enable signal into the amplifier, such that the amplifier can be switched off to reduce current consumption whenever the second path is not selected.

15. The method of claim 11 further comprising inputting a bypass signal originating from the transceiver into the amplifier, wherein the bypass signal causes the Bluetooth signals and WLAN signals to pass through the amplifier without amplification when the second path is selected, but no gain is required.

16. The method of claim 11 further comprising multiplexing the second and third paths using another switch that selects the Bluetooth receive path output by the divider when the RF front-end is receiving the Bluetooth signals on the second path, and selects the third path when the RF front-end is transmitting the Bluetooth signals.

17. A system, comprising:

an antenna;

a transceiver;

a front-end coupled between the antenna and the transceiver, the front-end configured to share transmissions and receptions of Bluetooth signals and WLAN signals, the front-end comprising;

a switch coupled to the antenna;

a first path coupled between the switch and the transceiver dedicated to transmissions of the WLAN signals;

a second path coupled between the switch and the transceiver dedicated to simultaneous receptions of the Bluetooth signals and the WLAN signals; and

a third path coupled between the switch and the transceiver, the third path dedicated to;

transmissions of the Bluetooth signals when a WLAN link is active;

transmissions and receptions of the Bluetooth signals when the WLAN link is active but in a power save state; and

transmissions and receptions of the Bluetooth signals when the WLAN link is inactive;

wherein the switch controls which of the first, second, and third paths to connect to the antenna.

18. The system of claim 17 wherein the second path includes a low noise amplifier coupled between the switch and a divider, wherein the low noise amplifier is shared by the Bluetooth signals and the WLAN signals received from the antenna, wherein the low noise amplifier amplifies the Bluetooth signals and the WLAN signals to compensate for a loss of signal strength, and outputs amplified Bluetooth and WLAN signals to the divider, and wherein the divider splits the amplified Bluetooth and WLAN signals onto a WLAN receive path and a Bluetooth receive path.

19. The system of claim 18 wherein the WLAN receive path is coupled to the transceiver, and the Bluetooth receive path is coupled to an input of the third path for Bluetooth receptions.