US-12627321-B2 - Radio frequency front end having shared path with common filter

Abstract

Radio frequency front end modules are provided. In one aspect, a front end system includes at least one power amplifier configured to amplify a transmit radio frequency signal, at least one low noise amplifier configured to receive a receive radio frequency signal, an output node coupled to an antenna. The front end system further includes at least one switch configured to selectively couple the output node to the at least one power amplifier during a transmit period and to the at least one low noise amplifier during a receive period, at least one transmit filter coupled between the power amplifier and the at least one switch, and at least one receive filter coupled between the low noise amplifier and the at least one switch.

Inventors

• Joel Richard King
• Tianming Chen
• Shayan Farahvash
• Stephane Richard Marie WLOCZYSIAK
• Anand Raghavan
• David Richard Pehlke

Assignees

• SKYWORKS SOLUTIONS, INC.

Dates

Publication Date

20260512

Application Date

20240429

Claims (20)

1. 1 . A radio frequency front end system comprising: a first transmit amplifier and a first receive amplifier; a first switch configured to selectively couple an output node to the first transmit amplifier or to the first receive amplifier; a first transmit filter coupled between the first transmit amplifier and the first switch, and a first receive filter coupled between the first receive amplifier and the first switch; a common filter coupled between the first switch and the output node, the common filter together with the first transmit filter configured to band-pass a first radio frequency range and together with the first receive filter configured to band-pass a second radio frequency range different than the first radio frequency range; and a second transmit amplifier, a second receive amplifier, a second transmit filter, a second receive filter, a first multiplexer, and a second multiplexer, the first multiplexer including the first transmit filter and the second transmit filter, and the second multiplexer including the first receive filter and the second receive filter.
2. 2 . The radio frequency front end system of claim 1 wherein the first switch is further configured to selectively couple one of the first multiplexer and the second multiplexer to the output node.
3. 3 . The radio frequency front end system of claim 1 further comprising a transmit supplemental filter, a receive supplemental filter, and a second switch ganged together with the first switch, and the second switch configured to selectively couple the transmit supplemental filter to the first transmit amplifier during a transmit period and to couple the receive supplemental filter to the first receive amplifier during a receive period.
4. 4 . The radio frequency front end system of claim 3 wherein the transmit supplemental filter includes a shunt filter and the receive supplemental filter includes a shunt filter.
5. 5 . The radio frequency front end system of claim 3 wherein the transmit supplemental filter and the receive supplemental filter include notch filters.
6. 6 . A radio frequency front end system comprising: a first transmit amplifier and a first receive amplifier; a first switch configured to selectively couple an output node to the first transmit amplifier or to the first receive amplifier; a first transmit filter coupled between the first transmit amplifier and the first switch, and a first receive filter coupled between the first receive amplifier and the first switch; a common filter coupled between the first switch and the output node, the common filter together with the first transmit filter configured to band-pass a first radio frequency range and together with the first receive filter configured to band-pass a second radio frequency range different than the first radio frequency range; and a second transmit amplifier, a second receive amplifier, a first filter bank including the first transmit filter and a second transmit filter, and a second filter bank including the first receive filter and a second receive filter.
7. 7 . The radio frequency front end system of claim 6 wherein the first switch is further configured to selectively couple one of the first transmit filter and the second transmit filter and one of the first receive filter and the second receive filter to the output node simultaneously.
8. 8 . The radio frequency front end system of claim 6 further comprising a transmit supplemental filter, a receive supplemental filter, and a second switch ganged together with the first switch, and the second switch configured to selectively couple the transmit supplemental filter to the first transmit amplifier during a transmit period and to couple the receive supplemental filter to the first receive amplifier during a receive period.
9. 9 . A radio frequency front end system comprising: a first transmit amplifier and a first receive amplifier; a first switch configured to selectively couple an output node to the first transmit amplifier or to the first receive amplifier; a first transmit filter coupled between the first transmit amplifier and the first switch, and a first receive filter coupled between the first receive amplifier and the first switch; a common filter coupled between the first switch and the output node, the common filter together with the first transmit filter configured to band-pass a first radio frequency range and together with the first receive filter configured to band-pass a second radio frequency range different than the first radio frequency range; and a second transmit amplifier, a second receive amplifier, and a second switch, the first transmit filter including a transmit diplexer, the first receive filter including a receive diplexer, the second switch configured to selectively couple the output node to the second transmit amplifier or to the second receive amplifier.
10. 10 . The radio frequency front end system of claim 9 further comprising a transmit supplemental filter, a receive supplemental filter, and a second switch ganged together with the first switch, and the second switch configured to selectively couple the transmit supplemental filter to the first transmit amplifier during a transmit period and to couple the receive supplemental filter to the first receive amplifier during a receive period.
11. 11 . The radio frequency front end system of claim 10 wherein the transmit supplemental filter includes a shunt filter and the receive supplemental filter includes a shunt filter.
12. 12 . The radio frequency front end system of claim 10 wherein the transmit supplemental filter and the receive supplemental filter include notch filters.
13. 13 . A mobile device comprising: an antenna; a front end system coupled to the antenna and including a first transmit amplifier, a first receive amplifier, a first switch configured to selectively couple an output node to the first transmit amplifier or to the first receive amplifier, a first transmit filter coupled between the first transmit amplifier and the first switch, a first receive filter coupled between the first receive amplifier and the first switch, and a common filter coupled between the first switch and the output node, the common filter together with the first transmit filter configured to band-pass a first radio frequency range and together with the first receive filter configured to band-pass a second radio frequency range different than the first radio frequency range; and a transmit supplemental filter, a receive supplemental filter, and a second switch ganged together with the first switch, and the second switch configured to selectively couple the transmit supplemental filter to the first transmit amplifier during a transmit period and to couple the receive supplemental filter to the first receive amplifier during a receive period.
14. 14 . The mobile device of claim 13 wherein the front end system further includes a second transmit amplifier, a second receive amplifier, a second transmit filter, a second receive filter, a first multiplexer including the first transmit filter and the second transmit filter, and a second multiplexer including the first receive filter and the second receive filter.
15. 15 . The mobile device of claim 14 wherein the first switch is further configured to selectively couple one of the first multiplexer and the second multiplexer to the output node.
16. 16 . The mobile device of claim 13 further comprising a second transmit amplifier, a second receive amplifier, a first filter bank including the first transmit filter and a second transmit filter, and a second filter bank including the first receive filter and a second receive filter.
17. 17 . The mobile device of claim 16 wherein the first switch is further configured to selectively couple one of the first transmit filter and the second transmit filter and one of the first receive filter and the second receive filter to the output node simultaneously.
18. 18 . The mobile device of claim 13 further comprising a second transmit amplifier, a second receive amplifier, and a second switch, the first transmit filter including a transmit diplexer, the first receive filter including a receive diplexer, the second switch configured to selectively couple the output node to the second transmit amplifier or to the second receive amplifier.
19. 19 . The mobile device of claim 13 wherein the transmit supplemental filter and the receive supplemental filter include shunt filters.
20. 20 . The mobile device of claim 13 wherein the transmit supplemental filter and the receive supplemental filter include notch filters.

Description

CROSS-REFERENCE TO RELATED APPLICATION(S) Any and all applications for which a foreign or domestic priority claim is identified in the Application Data Sheet as filed with the present application are hereby incorporated by reference under 37 CFR 1.57. BACKGROUND Technological Field Aspects of this disclosure relate to radio frequency (RF) communication systems, and in particular, front end modules for use in RF communication systems. Description of the Related Technology RF communication systems include a front end which couples one or more antennas to transmit and receive paths that communicate the RF signals to/from a baseband system. During time-division duplexing (TDD) communication, the antennas may be connected to only one of the transmit and receive paths at a time. The front end further includes one or more filters configured to filter out frequencies from the RF signals that are not within a given communication band. Typically, the filters may be shared between the transmit and receive paths. SUMMARY OF CERTAIN INVENTIVE ASPECTS The systems, methods and devices of this disclosure each have several innovative aspects, no single one of which is solely responsible for the desirable attributes disclosed herein. In one aspect, there is provided a radio frequency front end system comprising: at least one power amplifier configured to amplify a transmit radio frequency signal; at least one low noise amplifier configured to receive a receive radio frequency signal; an output node coupled to an antenna; at least one switch configured to selectively couple the output node to the at least one power amplifier during a transmit period and to the at least one low noise amplifier during a receive period; at least one transmit filter coupled between the power amplifier and the at least one switch; at least one receive filter coupled between the low noise amplifier and the at least one switch; and a common filter coupled between the at least one switch and the output node. The at least one power amplifier can include a plurality of power amplifiers, and the at least one low noise amplifier can include a plurality of low noise amplifiers. The front end system can further comprise a first multiplexer including the at least one transmit filter and a second multiplexer including the at least one receive filter, wherein the at least one transmit filter includes a plurality of transmit filters and the at least one receive filter includes a plurality of receive filters. The at least one switch can be further configured to selectively couple one of the first and second multiplexers to the output node. The front end system can further comprise a first filter bank including the at least one transmit filter and a second filter bank including the at least one receive filter, wherein the at least one transmit filter includes a plurality of transmit filters and the at least one receive filter includes a plurality of receive filters. The at least one switch can be further configured to selectively couple one of the transit filters and one of the receiver filters to the output node simultaneously. The at least one power amplifier can include first and second power amplifiers, and the at least one low noise amplifier can include first and second low noise amplifiers, the at least one transmit filter can include a transmit diplexer, the at least one receive filter can include a receive diplexer, and the at least one switch includes a first switch and a second switch. The front end system can further comprise a transmit supplemental filter and a receive supplemental filter, the at least one switch can include a first switch and a second switch that are ganged together, and the second switch can be configured to selectively couple the transmit supplemental filter to the at least one power amplifier during the transmit period and to couple the receive supplemental filter the at least one low noise amplifier during the receive period. The transmit and receive supplemental filters can include shunt filters. The transmit and receive supplemental filters can include notch filters. In another aspect, there is provided a mobile device comprising: an antenna configured to transmit radio frequency signals to a base station; and a front end system coupled to the antenna and configured to transmit and receive the radio frequency signals from the antenna, the front end system including a at least one power amplifier configured to amplify a transmit radio frequency signal, at least one low noise amplifier configured to receive a receive radio frequency signal, at least one switch configured to selectively couple the antenna to the at least one power amplifier during a transmit period and to the at least one low noise amplifier during a receive period, at least one transmit filter coupled between the power amplifier and the at least one switch, at least one receive filter coupled between the low noise amplifier and the at least one switch, and a co