Acoustic Resonator Filter Bank System

Abstract

One example includes an acoustic resonator filter bank system. The system includes multiple passive filters configured to provide multiple filtered versions of a radio frequency (RF) input signal. The system also includes a filter bank comprising multiple filter blocks each configured to provide multiple passbands across a frequency spectrum. Each of the filter blocks includes an acoustic resonator. The system further includes a switch matrix configured to provide one of the filtered versions of the RF input signal to one of the filter blocks of the filter bank to provide an RF output signal having a frequency band corresponding to a respective one of the passbands.

Description

[Technical Field]

[0001] The present disclosure relates generally to communications, and more particularly to acoustic resonator filter bank systems. [Background technology]

[0002] Resonator circuits are implemented in a variety of different applications, such as for filtering frequency ranges. There are a variety of different types of resonators. One such type of resonator is an acoustic resonator that implements acoustic waves on an integrated circuit (IC). Acoustic resonators include bulk acoustic wave (BAW) resonators and standing acoustic wave (SAW) resonators. Acoustic wave resonators are designed to confine acoustic energy within the resonator and increase the quality factor (Q) of the resonator. As an example, a conventional acoustic resonator can provide effective filtering in a narrow band (e.g., about + / - 5 dB) around a center frequency. Summary of the Invention

[0003] One example includes an acoustic resonator filter bank system. The system includes multiple passive filters configured to provide multiple filtered versions of a radio frequency (RF) input signal. The system also includes a filter bank having multiple filter blocks each configured to provide multiple passbands across a frequency spectrum. Each of the filter blocks includes an acoustic resonator. The system further includes a switch matrix configured to provide one of the filtered versions of the RF input signal to one of the filter blocks of the filter bank to provide an RF output signal having a frequency band corresponding to a respective one of the passbands.

[0004] Another example includes a method for filtering an RF input signal through an acoustic resonator filter bank system. The method includes providing the RF input signal to multiple passive filters of the acoustic resonator filter bank system. The multiple passive filters include a lowpass filter configured to provide a lowpass filtered version of the RF input signal, a bandpass filter configured to provide a bandpass filtered version of the RF input signal, and a highpass filter configured to provide a highpass filtered version of the RF input signal. The method includes receiving each of the lowpass filtered, bandpass filtered, and highpass filtered versions of the RF input signal, and providing multiple selection switching signals to a switch matrix configured to selectively switch one of the lowpass filtered, bandpass filtered, and highpass filtered versions of the RF input signal to one of multiple filter blocks of the filter bank. Each of the plurality of filter blocks includes an acoustic resonator and is configured to provide a first passband, a second passband higher than the first passband, and a third passband higher than the second passband to provide an RF output signal having a frequency band corresponding to a respective one of the first passband, the second passband, and the third passband.

[0005] Another example includes an integrated circuit (IC) including an acoustic resonator filter bank system. The system includes an input switch configured to provide an RF input signal to one of a plurality of filter paths. The system also includes a plurality of multiple passive filters, each associated with a respective one of the plurality of filter paths. Each of the plurality of multiple passive filters may be configured to provide multiple filtered versions of the RF input signal in response to receiving the RF input signal from the input switch. The system also includes a plurality of filter banks, each associated with a respective one of the plurality of filter paths. Each of the plurality of filter banks may include a plurality of filter blocks, each configured to provide multiple passbands across a frequency spectrum. Each of the plurality of filter blocks includes an acoustic resonator. The system further includes a plurality of switch matrices, each associated with a respective one of the plurality of filter paths. Each of the plurality of switch matrices is configured to provide one of the multiple filtered versions of the RF input signal to one of the plurality of filter blocks of a respective one of the plurality of filter banks to provide an RF output signal having a frequency band corresponding to a respective one of the multiple passbands. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 is an example block diagram of an acoustic resonator filter bank system. [Figure 2] FIG. 2 is a diagram illustrating an example of an acoustic resonator filter bank system. [Figure 3] FIG. 3 is an exemplary diagram of a filter block. [Figure 4] FIG. 4 is an exemplary diagram of a filter block response. [Figure 5] FIG. 5 illustrates an example method for filtering an RF input signal through an acoustic resonator filter bank system. DETAILED DESCRIPTION OF THE INVENTION

[0007] The present disclosure relates generally to communications, and more particularly to an acoustic resonator filter bank system. The acoustic resonator filter bank system can be implemented in various communication systems, such as in the transmit and / or receive paths of a wireless transceiver. The acoustic resonator filter bank system includes one or more filter paths that can be selected to provide selective filtering of a radio frequency (RF) input signal across a frequency spectrum. Each of the filter paths includes a filter bank, and each of the filter banks includes a plurality of filter blocks each configured to provide a plurality of harmonically related passbands. Each of the plurality of filter blocks includes a plurality of filter elements, each including an acoustic resonator and a capacitive network. As an example, the acoustic resonator can be configured as a combined overtone resonator (COR). As another example, the capacitive network can include at least one capacitor in parallel with the acoustic resonator.

[0008] Each filter path of the acoustic resonator filter bank system also includes multiple passive filters configured to receive an RF input signal and provide multiple filtered versions of the RF input signal. For example, the multiple passive filters may include a low-pass filter configured to provide a low-pass filtered version of the RF input signal, a band-pass filter configured to provide a band-pass filtered version of the RF input signal, and a high-pass filter configured to provide a high-pass filtered version of the RF input signal. Each filter path may also include a switching matrix. The switch matrix is ​​configured to receive a selection switching signal to selectively switch one of the multiple filtered versions of the RF input signal to one of the multiple filter blocks of the respective filter bank. As an example, the switch matrix may be formed from superlattice castellated gate field effect transistor (SLCFET) switches to accommodate a wideband of the RF input signal. Thus, based on which of the multiple filtered versions of the RF input signal is provided to a given one of the multiple filter blocks, the filter block can provide an RF output signal having a frequency band corresponding to a specific one of the multiple passbands of the filter block.

[0009] For example, the passbands of each of the filter blocks may be distinct, so that the passbands across all of the filter blocks can span the entire frequency spectrum without interruption. Thus, by selectively switching one of the filtered versions of the RF input signal to a given one of the filter blocks of a given filter path, the acoustic resonator filter bank system can provide a frequency band of the RF output signal corresponding to a single passband across the entire frequency spectrum. Thus, the acoustic resonator filter bank system can provide specific passband selectivity across a wide RF frequency spectrum. As another example, based on the structure of the filter blocks of the acoustic resonator filter bank system, the acoustic resonator filter bank system can be implemented on an integrated circuit to provide a compact filtering package that can provide selective filtering across frequencies in the frequency spectrum that differ by an order of magnitude or more in wavelength. Thus, the acoustic resonator filter bank system can provide flexible filtering across a wide frequency spectrum on a single, compact IC chip.

[0010] 1 shows an example block diagram of an acoustic resonator filter bank system 100. Acoustic resonator filter bank systems can be implemented in various communication systems, such as in the transmit and / or receive paths of a wireless transceiver. As described herein, the acoustic resonator filter bank system, in the example of FIG. 1, filters a signal RF IN The acoustic resonator filter bank system 100 can provide selective passband filtering of a radio frequency (RF) input signal, denoted as , over a wide bandwidth of a broad spectrum. As an example, the acoustic resonator filter bank system 100 can be fabricated within an integrated circuit (IC).

[0011] The acoustic resonator filter bank system 100 receives an RF input signal RF IN and the input switching signal SW IN. Thus, the input switch 102 is configured to receive the input switching signal SW IN In response to the state of the RF input signal RF IN to a single filter path among multiple (N) filter paths, where N is a positive integer. As an example, the input switch 102 may selectively provide an RF input signal RF IN The RF input signal RF may be formed from one or more superlattice castellated gate field effect transistor (SLCFET) switches to accommodate a wide band of RF signals. As another example, instead of an SLCFET switch, other types of low-loss RF switches, such as material phase-change switches (e.g., germanium telluride (GeTe) switches), may be implemented. As described in more detail herein, each of the multiple frequency paths may be configured to receive an RF input signal RF. IN The frequency bands may correspond to distinct passbands in the frequency spectrum associated with the

[0012] The acoustic resonator filter bank system 100 also includes a plurality (N) of multiple passive filters 104, each associated with a respective one of the plurality of filter paths. The input switch 102 couples an RF input signal RF to one of the plurality of multiple passive filters 104. IN so that each one of the plurality of multiple passive filters 104 is configured to provide an RF input signal RF IN The RF input signal RF is configured to provide multiple filtered versions of the RF input signal RF. IN A set of multiple filtered versions of the RF input signal RF is shown at 106. For example, each of the multiple passive filters 104 may filter the RF input signal RF IN and a low pass filter configured to provide a low pass filtered version of an RF input signal, RF IN and a bandpass filter configured to provide a bandpass filtered version of an RF input signal, RF IN and a high-pass filter configured to provide a high-pass filtered version of the RF input signal RFIN The multiple filtered versions 106 of may each have a relatively wide frequency band to encapsulate large variations in the narrower passbands, as described in more detail herein.

[0013] The acoustic resonator filter bank system 100 also includes a plurality (N) of switch matrices 108 and a plurality (N) of filter banks 110, each associated with a respective one of a plurality of filter paths. Each of the plurality of filter banks 110 includes a plurality of filter blocks 112. Each of the plurality of filter blocks 112 includes a plurality of filter elements, each including an acoustic resonator and a capacitive network. As an example, the acoustic resonator may be configured as a coupled harmonic resonator (COR) and may be provided in parallel with the capacitive network. The arrangement and characteristics of the acoustic resonator and the capacitive network in each of the plurality of filter elements may provide a passband for each one of the plurality of filter blocks 112 that can provide a large bandwidth (e.g., approximately 10%) of the passband provided by the respective filter block 112.

[0014] Each of the plurality of switch matrices 108 outputs a selection switching signal SW SEL and receives the RF input signal RF IN to one of the plurality of filter blocks 112 of the respective filter banks 110. As an example, the switch matrix may be configured to selectively switch one of the plurality of filtered versions 106 of the RF input signal RF IN Therefore, the RF input signal RF IN is provided to a given one of the plurality of filter blocks 112, the filter block 112 may generate an RF output RF having a frequency band corresponding to a particular one of the passbands of the respective filter block 112. OUTA signal can be provided.

[0015] 2 shows an example diagram of an acoustic resonator filter bank system 200. The acoustic resonator filter bank system can be implemented in various communication systems, such as in the transmit and / or receive paths of a wireless transceiver. The acoustic resonator filter bank system 200 can correspond to the acoustic resonator filter bank system 100 in the example of FIG. 1. Accordingly, reference will be made to the example of FIG. 1 in the following description of the example of FIG. 2. As an example, the acoustic resonator filter bank system 200 can be fabricated in an IC.

[0016] The acoustic resonator filter bank system 200 receives an RF input signal RF IN and the input switching signal SW IN 2. The input switch 202 is shown in the example of FIG. 2 as a single-pole, triple-throw (SP3T) switch, and thus configured to receive the RF input signal RF IN to one of three filter paths indicated at 204, 206, and 208. Thus, the integer N in the example of FIG. 1 is shown as N=3 in the example of FIG. 2. As an example, the input switch 202 selectively provides an RF input signal RF IN It can be formed from one or more SLCFET switches to accommodate a wide bandwidth of

[0017] Acoustic resonator filter bank system 200 includes a first multiple passive filter 210 associated with first filter path 204, a second multiple passive filter 212 associated with second filter path 206, and a third multiple passive filter 214 associated with third filter path 208. Each of multiple passive filters 210, 212, and 214 provides a low-pass filtered version of an RF input signal, RF INLPX and a low-pass filter configured to provide a band-pass filtered version of the RF input signal, RF INBPXand a bandpass filter configured to provide a high-pass filtered version of the RF input signal, RF INHPX where X corresponds to the first, second, or third of the multiple passive filters 210, 212, or 214, respectively. INLPX , R.F. INBPX , and RF INHPX may each have a relatively wide frequency band to encompass large variations in the narrower passbands, as will be described in more detail herein.

[0018] Acoustic resonator filter bank system 200 includes a first switch matrix 216 coupled to a first multiple passive filter 210, a second switch matrix 218 coupled to a second multiple passive filter 212, and a third switch matrix 220 coupled to a third multiple passive filter 212. Each of switch matrices 216, 218, and 220 is connected to a select switching signal SW SELX a filtered version of the RF input signal RF INLPX , R.F. INBPX , and RF INHPX to a single output of a respective one of switch matrices 216, 218, and 220, where X corresponds to the first, second, or third of switch matrices 216, 218, and 220, respectively. As an example, switch matrices 216, 218, and 220 are configured to provide one of the RF input signals RF IN To accommodate a wide bandwidth, it can be made from SLCFET switches.

[0019] The acoustic resonator filter bank system 200 includes a first filter bank 222 coupled to a first switch matrix 216, a second filter bank 224 coupled to a second switch matrix 218, and a third filter bank 226 coupled to a third switch matrix 220. Each of the filter banks 222, 224, and 226 includes three filter blocks 228 designated “filter block X_Z,” where X corresponds to the first, second, or third filter block of the filter banks 222, 224, and 226, respectively, and Z corresponds to the first, second, or third filter block of the filter banks 222, 224, and 226, respectively. Each of the filter blocks 228 is configured to provide a distinct set of passbands, related by harmonics (e.g., insertion harmonics). The distinct passbands may be provided based on physical and / or circuit characteristics associated with each filter block 228.

[0020] Figure 3 shows an example diagram of a filter block 300. The filter block 300 can correspond to any one of the filter blocks 228 in the example of Figure 2. Therefore, in the following description of the example of Figure 3, reference will be made to the example of Figure 2.

[0021] The filter block 300 includes a plurality of (Y) filter elements 302, where Y is a positive integer. Each filter element 302 includes an acoustic resonator 304, a capacitor C S , and another capacitor C V In the example of FIG. 3, the capacitor is shown as a variable capacitor (varactor), resulting in a voltage V TN But the capacitor C V Alternatively, a capacitor C V can have a fixed capacitance or be a capacitor C S and C V can also be combined into a single equivalent capacitance.

[0022] The acoustic resonator 304 is, in the example of FIG. 3, a first capacitor C R1 and inductor L R and a first capacitor C R1 and inductor L R The series arrangement of the second capacitor C R2 The circuit configuration of the acoustic resonator 304 can represent the operating characteristics of the acoustic resonator 304. For example, the first capacitor C R1 , the second capacitor C R2 , and inductor L R The value of may be based on the physical characteristics (e.g., substrate dimensions) of the acoustic resonator 304. The filter elements 302 may be symmetrically positioned with respect to the first, last, and middle filter elements 302 to provide proper impedance matching and filter matching characteristics.

[0023] As an example, the acoustic resonator 304 may be configured as a COR (e.g., an aluminum nitride (AlN) COR). Thus, the acoustic resonator 304 receives an RF input signal RF IN The COR can exhibit a high quality factor (Q) at frequencies both above and below a given frequency range (e.g., Ka band). For example, the COR can operate with a Q between about 400 and about 1000. Additionally, acoustic resonator 304 configured as a COR provides a shape factor selectivity of about 1.03 to provide a high Q of approximately 1.03 for RF input signal RF. IN Such selectivity can achieve approximately 60 dB of rejection at approximately 50 MHz on either side of the 3.5 GHz bandwidth, thus providing significantly greater rejection than conventional acoustic resonator filters (which, for example, exhibit a selectivity of approximately 1.5).

[0024] Acoustic resonator 304, capacitor C S , and capacitor C V The parallel arrangement of capacitor C in parallel with acoustic resonator 304 can provide significantly improved filter characteristics over conventional filters. S and CV The split capacitance provided by can provide the ability to tune the filter element 302 over a wide frequency range with minimal impact on the quality factor Q and insertion loss. As an example, the capacitor C V can be configured as a barium strontium titanate (BST) varactor, which allows a tuning range of about 33% with a loss tangent of about 0.006 and a quality factor Q of about 40 at a frequency of about 18 GHz. Thus, a capacitor C in parallel with acoustic resonator 304 S and C V The split capacitor configuration can provide a wide range of frequency tuning without causing performance degradation of the filter block 300.

[0025] In the example of Figure 3, each of the plurality of filter elements 302 is disposed between a filter path node 306 and a low voltage rail, shown as ground in the example of Figure 3. Each of the plurality of filter path nodes 306 is connected to a capacitor C for a set of Y filter elements in the example of Figure 3. FP_1 ~C FP_Y+1 Therefore, the filter path capacitor C FP_1 ~C FP_Y+1 The number of filter elements 302 is one more than the number of Y filter elements 302. In the example of FIG. INF The filtered version of the RF input signal, denoted as FP_1 ~C FP_Y+1 Therefore, the filter path capacitor C FP_1 ~C FP_Y+1 Based on the placement of filter elements 302 between the filter blocks 300, the filter block 300 is configured to provide multiple harmonically related passbands. As an example, the passbands may each have a bandwidth of about 10%.

[0026] Referring back to the example of FIG. 2, the plurality of filter blocks 228 in each of the filter banks 222, 224, and 226 each filter the RF input signal RFIN The filter bank system 200 may provide a distinct set of passbands across a frequency spectrum associated with a frequency band of interest. For example, each of the filter blocks 228 may provide a first passband, a second passband higher than the first passband, and a third passband higher than the second passband, where the first passband, the second passband, and the third passband are harmonically related. As an example, based on the bandwidth of the passbands of each of the filter blocks 228, the center frequencies of the passbands may be selected such that the passbands as a whole can collectively span the entire frequency spectrum. Thus, as described herein, the acoustic resonator filter bank system 200 may be configured to provide selectivity for any passband of interest in the frequency spectrum.

[0027] 2, each of the filter blocks 228 of the first filter bank 222 is coupled to a respective one of the outputs of the switch matrix 216, each of the filter blocks 228 of the second filter bank 224 is coupled to a respective one of the outputs of the switch matrix 218, and each of the filter blocks 228 of the third filter bank 226 is coupled to a respective one of the outputs of the switch matrix 220. As explained above, each of the switch matrices 216, 218, and 220 generates a filtered version of the RF input signal, RF INLPX , R.F. INBPX , and RF INHPX to a single output of a respective one of switch matrices 216, 218, and 220, and thus to a respective one of filter blocks 228 in a respective one of filter banks 222, 224, and 226. Thus, a filtered version of the RF input signal, RF INLPX , R.F. INBPX , and RF INHPXis provided to a respective one of the plurality of filter blocks 228, each filter block 228 generates an RF output signal RF having a frequency band corresponding to one of the first, second, and third passbands associated with the respective filter block 228. OUT can be output.

[0028] In the example of FIG. 2, the filter block 228 generates a filtered RF output signal RF OUT to a signal demultiplexer 230 coupled to all of the filter blocks 228 to generate an RF output signal RF from the acoustic resonator filter bank system 200. OUT As an example, the signal demultiplexer 230 may be implemented using a set of SLCFET switches. Alternatively, the signal demultiplexer 230 may instead be implemented as a passive signal combiner. Thus, the acoustic resonator filter bank system 200 receives an RF input signal RF IN to selectively filter an RF output signal RF having a frequency band corresponding to a single passband within a frequency spectrum spanning all of the passbands of the plurality of filter blocks 228. OUT can be provided.

[0029] 4 shows an example diagram 400 of filter block responses. Diagram 400 shows the passbands of each of filter blocks 228. Therefore, in the following description of the example of FIG. 4, reference is made to the example of FIG.

[0030] Diagram 400 includes a first frequency response 402 corresponding to a first filter block 228 (“Filter Block 1_1”) of first filter bank 222, a second frequency response 404 corresponding to a second filter block 228 (“Filter Block 1_2”) of first filter bank 222, and a third frequency response 406 corresponding to a third filter block 228 (“Filter Block 1_3”) of first filter bank 222. Diagram 400 includes a fourth frequency response 408 corresponding to a first filter block 228 (“Filter Block 2_1”) of second filter bank 224, a fifth frequency response 410 corresponding to a second filter block 228 (“Filter Block 2_2”) of second filter bank 224, and a sixth frequency response 412 corresponding to a third filter block 228 (“Filter Block 2_3”) of second filter bank 224. Diagram 400 further includes a seventh frequency response 414 corresponding to the first filter block 228 of third filter bank 226 ("Filter Block 3_1"), an eighth frequency response 416 corresponding to the second filter block 228 of third filter bank 226 ("Filter Block 3_2"), and a ninth frequency response 418 corresponding to the third filter block 228 of third filter bank 226 ("Filter Block 3_3"). Each of frequency responses 402, 404, 406, 408, 410, 412, 414, 416, and 418 includes three distinct harmonically related passbands. By way of example, each of the passbands may be dependent on the physical characteristics of acoustic resonator 304 and / or the capacitance of capacitor C V and C S Based on the characteristics of the filter block 228, such as the capacitance value of the filter block 228, the bandwidth may be approximately 10%.

[0031] Diagram 400 shows the frequency range from lowest frequency f1 to highest frequency f 27 The frequency spectrum covers frequencies f1 to f 274, the passbands of frequency responses 402, 404, 406, 408, 410, 412, 414, 416, and 418 generally range from just below lowest frequency f1 (based on the bandwidth of the passbands centered at frequency f1) to frequencies f 27 (based on the bandwidth of the passband centered at f) 27 , 412, 414, 416, and 418. Thus, the passbands of the frequency responses 402, 404, 406, 408, 410, 412, 414, 416, and 418 can extend seamlessly across the entire frequency spectrum up to frequencies slightly higher than the RF input signal RF. IN can be selectively applied to include any frequency within the frequency spectrum of diagram 400.

[0032] As described above in the example of FIG. 2, each of the multiple passive filters 210, 212, and 214 filters the RF input signal RF IN and a low pass filter configured to provide a low pass filtered version of an RF input signal, RF IN and a bandpass filter configured to provide a bandpass filtered version of an RF input signal, RF INand a high-pass filter configured to provide a high-pass filtered version of the frequency response 402. The multiple passive filters 210, 212, and 214 may be tuned differently relative to one another to filter different frequencies associated with the frequencies of the passbands of the filter blocks 228 of the respective filter banks 222, 224, and 226. In the example of FIG. 4, diagram 400 includes a first dashed line 420 and a second dashed line 422 that represent filter set points of the multiple passive filters 210, 212, and 214. Dashed lines 420 and 422 are provided by way of example and may not represent actual or specific filter set points relative to and / or for scaling with the passbands of the frequency responses 402, 404, 406, 408, 410, 412, 414, 416, and 418.

[0033] For example, dashed line 420 may represent an approximate frequency below which the low-pass filter portions of multiple passive filters 210, 212, and 214 may provide a low-pass of the frequency spectrum in diagram 400. Similarly, dashed line 422 may represent an approximate frequency above which the high-pass filter portions of multiple passive filters 210, 212, and 214 may provide a high-pass of the frequency spectrum in diagram 400. Similarly, dashed lines 420 and 422 may represent approximate frequencies between which the band-pass filter portions of multiple passive filters 210, 212, and 214 may provide a band-pass of the frequency spectrum in diagram 400. Thus, as described above, the combination of multiple passive filters 210, 212, and 214 with filter block 228, as provided by input switch 202 and switch matrices 216, 218, and 220, allows any one particular bandpass of filter block 228 to be filtered by the RF input signal RF IN Select the RF output signal RF as the passband for OUT You can decide whether to provide

[0034] Still referring to FIG. 2, as a first example, the input switch 202 receives an input switching signal SW IN is switched to the first state by IN can be provided to the first filter path 204. Thus, the RF input signal RF IN is provided to the first passive multiplex filter 210. Thus, the first passive multiplex filter 210 provides a filtered version of the RF input signal, RF INLP1 , R.F. INBP1 , and RF INHP1 to the first switch matrix 216. The selection switching signal SW SEL1 is a filtered version of the RF input signal to be provided to one of the filter blocks 228 of the first filter bank 222. INLP1 , R.F. INBP1 , and RF INHP1 For example, the selection switching signal SW SEL1 is a high-pass filtered version RF of the RF input signal to be provided to the second filter block 228 (“Filter Bank 1_2”) of the first filter bank 222. INHP1 Thus, as shown in the example of FIG. 4, a high-pass filtered version RF of the RF input signal is provided to the second filter block 228 (“Filter Bank 1_2”) of the first filter bank 222. INHP1 is f as shown by the dotted line 424. 20 Therefore, the frequency f 20 an RF output signal RF having a frequency band corresponding to a passband having a center frequency at OUT is provided.

[0035] As a second example, the input switch 202 receives an input switching signal SW IN and is switched to a second state by INcan be provided to the second filter path 206. Thus, the RF input signal RF IN is provided to the second passive multiplex filter 212. Thus, the second passive multiplex filter 212 provides a filtered version of the RF input signal, RF INLP2 , R.F. INBP2 , and RF INHP2 to the second switch matrix 218. The selection switching signal SW SEL2 is a filtered version of the RF input signal to be provided to one of the filter blocks 228 of the second filter bank 224. INLP2 , R.F. INBP2 , and RF INHP2 For example, the selection switching signal SW SEL2 is a low-pass filtered version of the RF input signal to be provided to the third filter block 228 (“Filter Bank 2_3”) of the second filter bank 224. INLP2 4, a low-pass filtered version of the RF input signal, RF_1, is provided to the second filter block 228 ("Filter Bank 2_3") of the second filter bank 224. INLP2 is associated with a passband having a center frequency at frequency f6, as shown by dotted line 426. Thus, an RF output signal RF OUT is provided.

[0036] As a third example, the input switch 202 receives an input switching signal SW IN to switch to a third state by IN can be provided to the third filter path 208. Thus, the RF input signal RF IN is provided to the third passive multiplex filter 214. Thus, the third passive multiplex filter 214 provides a filtered version of the RF input signal, RF INLP3 , R.F. INBP3 , and RFINHP3 to the third switch matrix 220. The selection switching signal SW SEL3 is a filtered version of the RF input signal to be provided to one of the filter blocks 228 of the third filter bank 226. INLP3 , R.F. INBP3 , and RF INHP3 For example, the selection switching signal SW SEL3 is a bandpass filtered version RF of the RF input signal to be provided to the first filter block 228 of the third filter bank 226 (“Filter Bank 3_1”). INBP3 Thus, as shown in the example of FIG. 4, a bandpass filtered version RF of the RF input signal is provided to the first filter block 228 of the third filter bank 226 ("Filter Bank 3_1"). INBP3 is f as shown by the dotted line 428. 16 Therefore, the frequency f 16 an RF output signal RF having a frequency band corresponding to a passband having a center frequency at OUT is provided.

[0037] Therefore, the examples of Figures 2 and 4 show that the RF input signal RF IN , into a given one of the plurality of filter blocks 228 of a given one of filter paths 204, 206, and 208, acoustic resonator filter bank system 200 generates an RF output signal RF corresponding to a single passband spanning the entire frequency spectrum of diagram 400. OUT3 shows that acoustic resonator filter bank system 200 can provide a frequency band of 100 kHz to 100 kHz. Therefore, acoustic resonator filter bank system 200 can provide a specific selectivity of the passband across a wide RF frequency spectrum. As described above, based on the structure of filter blocks 228 of filter banks 222, 224, and 226 of acoustic resonator filter bank system 200 (e.g., based on the structure of filter block 300 in the example of FIG. 3 ), acoustic resonator filter bank system 200 can be implemented on an integrated circuit to provide a passband with a difference of one or more orders of magnitude in wavelength (e.g., from frequency f to frequency f 27 The acoustic resonator filter bank system 200 can provide a compact filtering package that can provide selective filtering across a wide frequency spectrum (up to 100 kHz) on a single, compact IC chip.

[0038] With the above structural and functional features in mind, methods according to various embodiments of the present disclosure will be better understood with reference to Figure 5. It should be understood and appreciated that some aspects may occur in a different order and / or concurrently with other aspects in accordance with the present disclosure than that shown and described herein, and therefore the method of Figure 5 is not limited by the order shown. Furthermore, not all illustrated features are required to practice a method according to an embodiment of the present invention.

[0039] FIG. 5 illustrates a filter bank system (e.g., acoustic resonator filter bank system 100) configured to filter a radio frequency (RF) input signal (e.g., RF input signal RF IN) is provided to multiple passive filters (e.g., multiple passive filters 104) of an acoustic resonator filter bank system. The multiple passive filters may include a low-pass filter configured to provide a low-pass filtered version of the RF input signal, a band-pass filter configured to provide a band-pass filtered version of the RF input signal, and a high-pass filter configured to provide a high-pass filtered version of the RF input signal. At 504, multiple selection switching signals (e.g., selection switching signals SW SEL ) are provided to a switch matrix (e.g., switch matrix 108), which is configured to receive each of the low-pass filtered version, the band-pass filtered version, and the high-pass filtered version of the RF input signal and to selectively switch one of the low-pass filtered version, the band-pass filtered version, and the high-pass filtered version of the RF input signal to one of a plurality of filter blocks of the filter bank. Each of the plurality of filter blocks includes an acoustic resonator and provides a first passband, a second passband higher than the first passband, and a third passband higher than the second passband to generate an RF output signal (e.g., RF output signal RF ) having a frequency band corresponding to a respective one of the first passband, the second passband, and the third passband. OUT ) is configured to provide

[0040] The foregoing are examples of the present invention. Of course, it is not possible to describe every conceivable combination of components or methodologies for the purpose of illustrating the present invention, but those skilled in the art will recognize that many further combinations and permutations of the present invention are possible. Accordingly, the present invention is intended to embrace all such alterations, modifications, and variations that fall within the spirit and scope of the appended claims. Furthermore, when a disclosure or claim recites "a," "an," "a first," "another" element, or the equivalent thereof, it should be construed as including one or more such elements, and does not require or exclude two or more such elements. As used herein, the term "includes" means including without limitation. The term "based on" means based at least in part on. The technical ideas included in this disclosure are described below as appendices. (Appendix 1) 1. An acoustic resonator filter bank system, comprising: a multiple passive filter configured to provide multiple filtered versions of a radio frequency (RF) input signal; a filter bank including a plurality of filter blocks each configured to provide a plurality of passbands across a frequency spectrum, each of the plurality of filter blocks including an acoustic resonator; a switch matrix configured to provide one of the plurality of filtered versions of the RF input signal to one of the plurality of filter blocks of the filter bank to provide an RF output signal having a frequency band corresponding to a respective one of the plurality of passbands; A system comprising: (Appendix 2) 2. The system of claim 1, wherein each of the plurality of filter blocks includes a plurality of filter elements, and each of the plurality of filter elements includes the acoustic resonator in parallel with a capacitive network. (Appendix 3) 10. The system of claim 1, wherein the acoustic resonator is configured as a coupled harmonic resonator. (Appendix 4) 10. The system of claim 1, wherein a plurality of filter elements are each disposed between a respective one of a plurality of filter path nodes and a low voltage rail, and each of the plurality of filter blocks further includes a plurality of filter path capacitors connected between each of the plurality of filter path nodes. (Appendix 5) 2. The system of claim 1, wherein the switch matrix includes a plurality of superlattice castellated gate field effect transistor (SLCFET) switches configured to switch one of the plurality of filtered versions of the RF input signal to one of the plurality of filter blocks. (Appendix 6) 2. The system of claim 1, wherein the multiple passive filters are one of a plurality of multiple passive filters, each associated with a respective one of a plurality of filter paths, the filter bank is one of a plurality of filter banks, each associated with a respective one of the plurality of filter paths, and the switch matrix is ​​one of a plurality of switch matrices, each associated with a respective one of the plurality of filter paths, the system further comprising an input switch configured to provide the RF input signal to one of the plurality of filter paths. (Appendix 7) 7. The system of claim 6, wherein each of the plurality of filter blocks in each of the plurality of filter banks is configured to provide a plurality of distinct passbands across the frequency spectrum, such that the plurality of passbands collectively span the entire frequency spectrum. (Appendix 8) 10. The system of claim 1, wherein the plurality of passbands associated with each of the plurality of filter blocks include a first passband, a second passband higher than the first passband, and a third passband higher than the second passband, and the first passband, second passband, and third passband are harmonically related. (Appendix 9) 9. The system of claim 8, wherein the multiple passive filters include a lowpass filter configured to provide a lowpass filtered version of the RF input signal, a bandpass filter configured to provide a bandpass filtered version of the RF input signal, and a highpass filter configured to provide a highpass filtered version of the RF input signal, and the switch matrix is ​​configured to provide one of the lowpass, bandpass, and highpass versions of the RF input signal to one of the plurality of filter blocks to provide the RF output signal having a respective one of the first passband, the second passband, and the third passband. (Appendix 10) 10. An integrated circuit (IC) comprising the acoustic resonator filter bank system of claim 1. (Appendix 11) 1. A method for filtering a radio frequency (RF) input signal through an acoustic resonator filter bank system, comprising: providing the RF input signal to multiple passive filters of the acoustic resonator filter bank system, the multiple passive filters including a low pass filter configured to provide a low pass filtered version of the RF input signal, a band pass filter configured to provide a band pass filtered version of the RF input signal, and a high pass filter configured to provide a high pass filtered version of the RF input signal; providing a plurality of selection switching signals to a switch matrix configured to receive each of the low-pass filtered version, the band-pass filtered version, and the high-pass filtered version of the RF input signal and to selectively switch one of the low-pass filtered version, the band-pass filtered version, and the high-pass filtered version of the RF input signal to one of a plurality of filter blocks of a filter bank. each of the plurality of filter blocks includes an acoustic resonator and is configured to provide a first passband, a second passband higher than the first passband, and a third passband higher than the second passband to provide an RF output signal having a frequency band corresponding to a respective one of the first passband, the second passband, and the third passband. (Appendix 12) 12. The method of claim 11, wherein each of the plurality of filter blocks includes a plurality of filter elements, each of the plurality of filter elements including the acoustic resonator in parallel with a capacitive network. (Appendix 13) 12. The method of claim 11, wherein the acoustic resonator is configured as a coupled harmonic resonator. (Appendix 14) providing an input switch signal to an input switch to provide the RF input signal to one of a plurality of filter paths; providing the RF input signal to the multiple passive filters includes providing the RF input signal to one of a plurality of multiple passive filters, each associated with a respective one of the plurality of filter paths; 12. The method of claim 11, wherein providing the select switching signal to the switch matrix comprises providing the select switching signal to a respective one of a plurality of switch matrices, each associated with a respective one of the plurality of filter paths, to selectively switch one of the lowpass filtered version, the bandpass filtered version, and the highpass filtered version of the RF input signal to one of the plurality of filter blocks of a respective one of a plurality of filter banks, each associated with a respective one of the plurality of filter paths. (Appendix 15) 15. The method of claim 14, wherein each of the plurality of filter blocks in each of the plurality of filter banks is configured to provide a plurality of distinct passbands across a frequency spectrum, the plurality of passbands collectively spanning the entire frequency spectrum. (Appendix 16) 1. An acoustic resonator filter bank system, comprising: an input switch configured to provide a radio frequency (RF) input signal to one of a plurality of filter paths; a plurality of multiple passive filters each associated with a respective one of the plurality of filter paths, each of the plurality of multiple passive filters configured to provide a plurality of filtered versions of the RF input signal in response to receiving the RF input signal from the input switch; a plurality of filter banks each associated with a respective one of the plurality of filter paths, each of the plurality of filter banks including a plurality of filter blocks each configured to provide a plurality of passbands across a frequency spectrum, each of the plurality of filter blocks including an acoustic resonator; a plurality of switch matrices each associated with a respective one of the plurality of filter paths, each of the plurality of switch matrices configured to provide one of the plurality of filtered versions of the RF input signal to one of the plurality of filter blocks of a respective one of the plurality of filter banks to provide an RF output signal having a frequency band corresponding to a respective one of the plurality of passbands; A system comprising: (Appendix 17) 17. The system of claim 16, wherein each of the plurality of filter blocks includes a plurality of filter elements, each of the plurality of filter elements including the acoustic resonator in parallel with a capacitive network. (Appendix 18) 17. The system of claim 16, wherein the acoustic resonator is configured as a coupled harmonic resonator. (Appendix 19) 17. The system of claim 16, wherein the plurality of passbands associated with each of the plurality of filter blocks of each of the plurality of filter banks include a first passband, a second passband higher than the first passband, and a third passband higher than the second passband, wherein the first passband, second passband, and third passband are harmonically related. (Appendix 20) 20. The system of claim 19, wherein each of the plurality of multiple passive filters includes a lowpass filter configured to provide a lowpass filtered version of the RF input signal, a bandpass filter configured to provide a bandpass filtered version of the RF input signal, and a highpass filter configured to provide a highpass filtered version of the RF input signal, and wherein each of the plurality of switch matrices is configured to provide one of the lowpass, bandpass, and highpass versions of the RF input signal to one of the plurality of filter blocks of a respective one of the plurality of filter banks to provide the RF output signal having a respective one of the first passband, the second passband, and the third passband.

Claims

1. 1. An acoustic resonator filter bank system, comprising: a plurality of multiple passive filters, each configured to provide a plurality of filtered versions of a radio frequency (RF) input signal, each of the plurality of multiple passive filters associated with a respective one of a plurality of filter paths; a plurality of filter banks, each of the plurality of filter banks associated with a respective one of the plurality of filter paths, each of the plurality of filter banks including a plurality of filter blocks configured to provide a plurality of passbands across a frequency spectrum, each of the plurality of filter blocks including an acoustic resonator; a plurality of switch matrices, each of the plurality of switch matrices associated with a respective one of the plurality of filter paths and configured to provide one of the plurality of filtered versions of the RF input signal to one of the plurality of filter blocks of a respective one of the plurality of filter banks to provide an RF output signal having a frequency band corresponding to a respective one of the plurality of passbands; A system comprising:

2. The system of claim 1 , wherein each of the plurality of filter blocks includes a plurality of filter elements, and each of the plurality of filter elements includes the acoustic resonator in parallel with a capacitive network.

3. The system of claim 1 , wherein the acoustic resonator is configured as a coupled harmonic resonator.

4. The system described in claim 2, wherein the plurality of filter elements are each arranged between a respective plurality of filter path nodes and a low voltage rail, and each of the plurality of filter blocks further includes a plurality of filter path capacitors connected between each of the plurality of filter path nodes.

5. 2. The system of claim 1, wherein the switch matrix includes a plurality of superlattice castellated gate field effect transistor (SLCFET) switches configured to switch one of the plurality of filtered versions of the RF input signal to one of the plurality of filter blocks.

6. The system of claim 1, further comprising an input switch configured to provide the RF input signal to one of the plurality of filter paths.

7. 2. The system of claim 1, wherein each of the plurality of filter blocks in each of the plurality of filter banks is configured to provide a plurality of distinct passbands across the frequency spectrum, such that the plurality of passbands collectively span the entire frequency spectrum.

8. 2. The system of claim 1, wherein the plurality of passbands associated with each of the plurality of filter blocks includes a first passband, a second passband higher than the first passband, and a third passband higher than the second passband, and the first passband, second passband, and third passband are harmonically related.

9. 9. The system of claim 8, wherein each of the plurality of multiple passive filters includes a lowpass filter configured to provide a lowpass filtered version of the RF input signal, a bandpass filter configured to provide a bandpass filtered version of the RF input signal, and a highpass filter configured to provide a highpass filtered version of the RF input signal, and the switch matrix is ​​configured to provide one of the lowpass, bandpass, and highpass versions of the RF input signal to one of the plurality of filter blocks to provide the RF output signal having a respective one of the first passband, the second passband, and the third passband.

10. 10. An integrated circuit (IC) comprising the acoustic resonator filter bank system of claim 1.

11. 1. A method for filtering a radio frequency (RF) input signal through an acoustic resonator filter bank system, comprising: providing the RF input signal to a plurality of multiple passive filters of the acoustic resonator filter bank system, each of the plurality of multiple passive filters being associated with a respective one of a plurality of filter paths, each of the plurality of multiple passive filters including: a low-pass filter configured to provide a low-pass filtered version of the RF input signal; a band-pass filter configured to provide a band-pass filtered version of the RF input signal; and a high-pass filter configured to provide a high-pass filtered version of the RF input signal; and Providing a plurality of select switching signals to respective ones of a plurality of switch matrices the plurality of switch matrices, each associated with a respective one of the plurality of filter paths, are configured to receive each of the low-pass filtered version, the band-pass filtered version, and the high-pass filtered version of the RF input signal and to selectively switch one of the low-pass filtered version, the band-pass filtered version, and the high-pass filtered version of the RF input signal to one of a plurality of filter blocks of a respective one of a plurality of filter banks, each associated with a respective one of the plurality of filter paths, each of the plurality of filter blocks including an acoustic resonator and configured to provide a first passband, a second passband higher than the first passband, and a third passband higher than the second passband to provide an RF output signal having a frequency band corresponding to a respective one of the first passband, the second passband, and the third passband.

12. The method of claim 11 , wherein each of the plurality of filter blocks includes a plurality of filter elements, each of the plurality of filter elements including the acoustic resonator in parallel with a capacitive network.

13. The method of claim 11 , wherein the acoustic resonators are configured as coupled harmonic resonators.

14. The method of claim 11 , further comprising providing an input switch signal to an input switch to provide the RF input signal to one of a plurality of filter paths.

15. 12. The method of claim 11 , wherein each of the plurality of filter blocks in each of the plurality of filter banks is configured to provide a plurality of distinct passbands across a frequency spectrum, the plurality of passbands collectively spanning the entire frequency spectrum.

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