MOBILE DEVICE FRONT END ARCHITECTURE FOR TIME DIVISION DUPLEXING

• US 20160134414A1
• Filed: 11/03/2015
• Published: 05/12/2016
• Est. Priority Date: 11/06/2014
• Status: Active Grant

• Current Assignee: Skyworks Solutions Incorporated
• Original Assignee: Skyworks Solutions Incorporated
• Inventors: Pehlke, David Richard
• Granted Patent: US 9,866,366 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04B 1/0057 using diplexing or multiplexing filters for selecting the desired band
• CPC Class Codes: H04L 5/14 Two-way operation using the same type of signal, i.e. duplex
• CPC Class Codes: H04L 5/1469 using time-sharing

Abstract

A switching circuit for use in a frequency division duplex (FDD) spectrum re-allocated for time division duplex (TDD) applications comprises a first filter configured to filter a TDD receive signal, a duplex filter configured to filter an FDD receive signal, and a plurality of switches configured to route the FDD receive signal from an antenna through the duplex filter to receiver circuitry and to route the TDD receive signal from the antenna through the first filter to the receiver circuitry such that the FDD and TDD receive signals share the FDD spectrum.

Claims

1. A switching circuit for use in a frequency division duplex (FDD) spectrum re-allocated for time division duplex (TDD) application, the switching circuit comprising:

a first filter configured to filter a TDD receive signal;

a duplex filter configured to filter an FDD receive signal; and

a plurality of switches configured to route the FDD receive signal from an antenna through the duplex filter to receiver circuitry and to route the TDD receive signal from the antenna through the first filter to the receiver circuitry, the FDD and TDD receive signals sharing the FDD spectrum.

2. The switching circuit of claim 1 wherein the duplex filter includes a surface acoustic wave (SAW) filter.

3. The switching circuit of claim 1 further comprising a second filter configured to filter a TDD transmit signal, the duplex filter further configured to filter an FDD transmit signal.

4. The switching circuit of claim 3 wherein the first filter, the second filter, and the duplex filter include bandpass filters.

5. The switching circuit of claim 3 wherein the plurality of switches are further configured to route the TDD transmit signal from transmitter circuitry through the second filter to the antenna, and to route the FDD transmit signal from the transmitter circuitry through the duplex filter to the antenna, the FDD and TDD transmit signals sharing a first frequency band of the FDD spectrum.

6. The switching circuit of claim 5 wherein the TDD transmit, TDD receive, FDD transmit, and FDD receive signals are radio frequency (RF) signals.

7. A wireless device including the switching circuit of claim 1.

8. A switching module for use in a frequency division duplex (FDD) spectrum re-allocated for time division duplex (TDD) application, the switching module comprising:

a switching circuit implemented in a first semiconductor die, the switching circuit including a first filter configured to filter a TDD receive signal, a duplex filter configured to filter an FDD receive signal, and a plurality of switches configured to route the FDD receive signal from an antenna through the duplex filter to receiver circuitry and to route the TDD receive signal from the antenna through the first filter to the receiver circuitry, the FDD and TDD receive signals sharing the FDD spectrum; and

at least one of a prefilter circuit, a post filter circuit, a power amplifier circuit, a switch circuit, a down converter circuit, and a modulator circuit implemented in a second semiconductor die.

9. The switching module of claim 8 wherein the duplex filter includes a surface acoustic wave (SAW) filter.

10. The switching module of claim 8 wherein the switching circuit further includes a second filter configured to filter a TDD transmit signal, the duplex filter further configured to filter an FDD transmit signal.

11. The switching module of claim 10 wherein the first filter, the second filter, and the duplex filter include bandpass filters.

12. The switching module of claim 10 wherein the plurality of switches are further configured to route the TDD transmit signal from transmitter circuitry through the second filter to the antenna and to route the FDD transmit signal from the transmitter circuitry through the duplex filter to the antenna, the FDD and TDD transmit signals sharing a first frequency band of the FDD spectrum.

13. The switching module of claim 8 wherein the duplex filter includes a film bulk acoustic resonator (FBAR) filter.

14. The switching module of claim 8 wherein the duplex filter includes a bulk acoustic wave (BAW) filter.

15. A wireless device including the switching module of claim 8.

16. A method to transmit and receive frequency division duplex (FDD) signals and time division duplex (TDD) signals in an FDD and TDD shared frequency band, the method comprising:

routing an FDD receive signal from an antenna to receiver circuitry through a duplex filter configured to filter the FDD receive signal; and

routing a TDD receive signal from the antenna to the receiver circuitry through a first filter configured to filter the TDD receive signal, the FDD and TDD receive signals sharing an FDD spectrum.

17. The method of claim 16 wherein the duplex filter includes a surface acoustic wave (SAW) filter.

18. The method of claim 16 further comprising routing an FDD transmit signal from the transmitter circuitry to the antenna through the duplex filter further configured to filter the FDD transmit signal.

19. The method of claim 18 further comprising routing a TDD transmit signal from the transmitter circuitry to the antenna through a second filter configured to filter the TDD transmit signal, the FDD and TDD transmit signals sharing the FDD spectrum.

20. The method of claim 19 wherein the duplex filter is selected from the group consisting of a surface acoustic wave (SAW) filter, a film bulk acoustic resonator (FBAR) filter, and a bulk acoustic wave (BAW) filter.