Passive acoustic resonator based RF receiver

• US 9,966,981 B2
• Filed: 01/25/2017
• Issued: 05/08/2018
• Est. Priority Date: 06/06/2013
• Status: Active Grant

• Current Assignee: Qorvo US, Inc. (Qorvo, Inc.)
• Original Assignee: Qorvo US, Inc. (Qorvo, Inc.)
• Inventors: Leipold, Dirk Robert Walter, Maxim, George, Scott, Baker
• Primary Examiner(s): PHU, SANH D
• Application Number:
  US15/415,538
• Publication Number:
  US 20170134058A1
• Time in Patent Office: 468 Days
• Field of Search: 455334
• CPC Class Codes: H03F 1/565 using inductive elements
• CPC Class Codes: H03F 2200/111 the amplifier being a dual or triple band amplifier, e.g. 900 and 1800 MHz, e.g. switched or not switched, simultaneously or not
• CPC Class Codes: H03F 2200/267 A capacitor based passive circuit, e.g. filter, being used in an amplifying circuit
• CPC Class Codes: H03F 2200/294 the amplifier being a low noise amplifier [LNA]
• CPC Class Codes: H03F 2200/451 the amplifier being a radio frequency amplifier
• CPC Class Codes: H03F 2203/7209 the gated amplifier being switched from a first band to a second band
• CPC Class Codes: H03F 3/19 with semiconductor devices only
• CPC Class Codes: H03F 3/245 with semiconductor devices only
• CPC Class Codes: H03F 3/68 Combinations of amplifiers, e.g. multi-channel amplifiers for stereophonics power amplifiers using a combination of several semiconductor amplifiers H03F3/211; combinations of amplifiers using coupling networks with distributed constants H03F3/602
• CPC Class Codes: H03F 3/72 Gated amplifiers, i.e. amplifiers which are rendered operative or inoperative by means of a control signal
• CPC Class Codes: H03H 2210/012 Centre frequency; Cut-off frequency
• CPC Class Codes: H03H 2210/025 Capacitor
• CPC Class Codes: H03H 2210/04 Filter calibration method
• CPC Class Codes: H03H 7/09 Filters comprising mutual inductance
• CPC Class Codes: H03H 7/1775 Parallel LC in shunt or branch path H03H7/1791 takes precedence
• CPC Class Codes: H03H 7/38 Impedance-matching networks
• CPC Class Codes: H03H 7/46 Networks for connecting several sources or loads, working on different frequencies or frequency bands, to a common load or source for use in multiplex transmission systems H04J1/00
• CPC Class Codes: H03H 9/64 using surface acoustic waves
• CPC Class Codes: H04B 1/1018 noise filters connected between the power supply and the receiver suppression or limitation of noise from electric apparatus H04B15/00; demodulation H03D; ripple filters H02M1/14; filters in general 95G, H03H; power supplies H04B1/1607
• CPC Class Codes: H04B 1/18 Input circuits, e.g. for coupling to an antenna or a transmission line coupling networks between antennas or lines and receivers independent of the nature of the receiver H03H
• CPC Class Codes: H04W 4/70 : Services for machine-to-machine communication [M2M] or machine type communication [MTC]
• CPC Class Codes: H04W 52/0209 : in terminal devices terminal devices per se H04W88/02
• CPC Class Codes: Y02D 30/70 : in wireless communication networks

Abstract

A radio frequency (RF) receiver, which has an RF filter and impedance matching circuit and an RF low noise amplifier (LNA), is disclosed. The RF filter and impedance matching circuit includes a first passive RF acoustic resonator; provides an RF bandpass filter having an RF receive band based on the first passive RF acoustic resonator; and presents an input impedance at an RF input and an output impedance at an RF output, such that a ratio of the output impedance to the input impedance is greater than 40. The RF LNA is coupled to the RF output.

Claims

1. A radio frequency (RF) receiver comprising:

an RF filter and impedance matching circuit comprising a first passive RF acoustic resonator, wherein the RF filter and impedance matching circuit is configured to;

provide an RF bandpass filter having an RF receive band based on the first passive RF acoustic resonator; and

present an input impedance at an RF input and an output impedance at an RF output, wherein a ratio of the output impedance to the input impedance is greater than 40;

a programmable capacitance circuit configured to provide a capacitance across the first passive RF acoustic resonator based on a receiver control signal, wherein a center frequency of the RF receive band is based on the capacitance; and

an RF low noise amplifier (LNA) coupled to the RF output.

2. The RF receiver of claim 1 wherein an RF signal path is between the RF input and the RF output, such that the first passive RF acoustic resonator is coupled between the RF signal path and a ground.

3. The RF receiver of claim 2 wherein the RF filter and impedance matching circuit further comprises an input impedance matching circuit coupled in the RF signal path between the RF input and the first passive RF acoustic resonator, wherein the input impedance matching circuit is configured to present the input impedance at the RF input.

4. The RF receiver of claim 3 wherein the input impedance matching circuit comprises an input capacitive element coupled in the RF signal path between the RF input and the first passive RF acoustic resonator.

5. The RF receiver of claim 2 wherein the RF filter and impedance matching circuit further comprises an output impedance matching circuit coupled in the RF signal path between the first passive RF acoustic resonator and the RF output, wherein the output impedance matching circuit is configured to present the output impedance at the RF output.

6. The RF receiver of claim 5 wherein the output impedance matching circuit comprises an output capacitive element coupled in the RF signal path between the first passive RF acoustic resonator and the RF output.

7. The RF receiver of claim 1 wherein the input impedance is between 40 ohms and 85 ohms.

8. The RF receiver of claim 1 wherein the ratio of the output impedance to the input impedance is greater than 150.

9. The RF receiver of claim 1 wherein a bandwidth of the RF receive band is less than 250 kilohertz.

10. The RF receiver of claim 1 wherein a tuning range of the center frequency is at least 10 megahertz.

11. The RF receiver of claim 1 further comprising:

a local oscillator (LO) comprising a second passive RF acoustic resonator, which is configured to resonate at an LO frequency, such that the LO is configured to provide an LO output signal having the LO frequency based on the second passive RF acoustic resonator; and

an RF mixer configured to down-convert an amplified RF receive signal using the LO output signal to provide a down-converted receive signal.

12. The RF receiver of claim 1 wherein:

the RF filter and impedance matching circuit is further configured to receive and filter an RF receive signal via the RF input to provide a filtered RF receive signal via the RF output;

the RF LNA is configured to receive and amplify the filtered RF receive signal to provide an amplified RF receive signal; and

an energy of the filtered RF receive signal is obtained entirely from the RF receive signal by the RF filter and impedance matching circuit.

13. The RF receiver of claim 1 wherein the first passive RF acoustic resonator is a bulk acoustic wave (BAW) RF resonator.

14. The RF receiver of claim 1 wherein the first passive RF acoustic resonator is a surface acoustic wave (SAW) RF resonator.

15. The RF receiver of claim 1 wherein the first passive RF acoustic resonator is a film bulk acoustic resonator (FBAR) RF resonator.

16. The RF receiver of claim 1 configured to function as an Internet of Things (IoT) RF receiver.

17. A radio frequency (RF) receiver comprising:

an RF filter and impedance matching circuit comprising a first passive RF acoustic resonator, wherein the RF filter and impedance matching circuit is configured to;

provide an RF bandpass filter having an RF receive band based on the first passive RF acoustic resonator; and

receive and filter an RF receive signal to provide a filtered RF receive signal;

a programmable capacitance circuit configured to provide a capacitance across the first passive RF acoustic resonator based on a receiver control signal, wherein a center frequency of the RF receive band is based on the capacitance;

an RF low noise amplifier (LNA) configured to receive and amplify the filtered RF receive signal to provide an amplified RF receive signal;

a local oscillator (LO) comprising a second passive RF acoustic resonator, which is configured to resonate at an LO frequency, such that the LO is configured to provide an LO output signal having the LO frequency based on the second passive RF acoustic resonator; and

an RF mixer configured to down-convert the amplified RF receive signal using the LO output signal to provide a down-converted receive signal.

18. The RF receiver of claim 17 wherein a tuning range of the center frequency is at least 10 megahertz.