Adjustable lobe shape for microphone arrays

Abstract

The present invention provides an array microphone system and method with adjustable lobe shape. The lobe shape of the pickup pattern in the array microphone can be adjusted by weighting the audio signals of a subset of the microphone elements that make up the array. The lobe shape can be adjusted in a direction independent of the steering vector of the lobe. The user can have greater control over the lobe, which can result in more efficient and optimal coverage of audio sources in the environment.

Description

[0001] Cross Reference

[0002] This application claims priority to U.S. Provisional Patent Application No. 62 / 733,779, filed on September 20, 2018, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present application generally relates to an array microphone with adjustable lobe shape. In particular, the present application relates to an array microphone that allows for more control over the shape of the lobe in a direction independent of the lobe's steering vector. Background Art

[0004] Meeting environments (e.g., conference halls, meeting rooms, video conferencing applications, etc.) may involve the use of microphones to capture sounds from various audio sources currently available in such environments. For example, such audio sources may include human speech. The captured sound may be spread to local listeners in the environment and / or other listeners away from the environment (e.g., via television broadcasts and / or webcasts) through amplified speakers (for sound reinforcement). The type of microphone and its placement in a particular environment may depend on the location of the audio source, physical space requirements, aesthetics, room layout, and / or other considerations. For example, in some environments, the microphone may be placed on a table or podium close to the audio source. For example, in other environments, the microphone may be mounted high to capture sound from the entire room. Therefore, microphones of various sizes, form factors, mounting options, and wiring options are available to meet the needs of a particular environment.

[0005] Traditional microphones typically have fixed polar patterns and few manually selectable settings. To capture sound in a conference environment, many traditional microphones may be used simultaneously to capture audio sources within the environment. However, traditional microphones also tend to capture unwanted audio, such as room noise, echo, and other undesirable audio elements. The use of many microphones exacerbates the capture of these unwanted noises.

[0006] Array microphones with multiple microphone elements may provide benefits such as steerable coverage or pickup patterns (with one or more lobes), which allows the microphone to focus on desired audio sources and reject unwanted sounds, such as room noise. The ability to steer the audio pickup pattern provides the benefit of being able to be less precise in microphone placement, and in this way, the array microphone is more forgiving. Furthermore, array microphones provide the ability to pick up multiple audio sources with one array microphone or unit, again due to the ability to steer the pickup pattern.

[0007] However, in certain environments and situations, the geometry of the lobes of the pickup pattern of the array microphone may not be optimal. For example, the size or layout of the room may be such that it cannot be efficiently covered by the lobes, or the default lobe shape may pick up unwanted noise when manipulated at the desired audio source. Similarly, if all the desired audio sources are too dispersed throughout the room, the default lobe shape may not cover such sources. As an example, unwanted or undesired audio sources may be picked up by the lobes. In another example, two nearby speakers may be more efficiently picked up by one stretched lobe rather than two default narrow lobes.

[0008] Therefore, there is an opportunity for array microphones to address these concerns. More specifically, there is an opportunity for array microphones to allow more control over the overall shape of the lobe to achieve more efficient and optimal coverage of the environment. Summary of the invention

[0009] The present invention intends to solve the above-mentioned problems by providing an array microphone system and method, which are designed to, among other things: (1) enable the shape of the lobe of the array microphone to be adjusted in a direction independent of the steering vector of the lobe; (2) select a subset of the microphone elements of the array microphone to perform lobe shape adjustment; and (3) determine weights for adjusting the lobe shape of the array microphone.

[0010] In one embodiment, an array microphone includes a processor and a plurality of microphone elements, each of which is configured to detect sound and output an audio signal. The processor can communicate with the plurality of microphone elements. The processor can be configured to: receive the audio signal from each of the plurality of microphone elements; shape one or more lobes based on combining the audio signals; and apply weights to the magnitude of the audio signal for one or more subsets of the plurality of microphone elements so that the shape of the one or more lobes is adjusted.

[0011] In another embodiment, a method for selecting one or more subsets of a plurality of microphone elements in an array microphone using a processor for adjusting the shape of a lobe of the array microphone is disclosed. The method may include: receiving a desired steering vector and a desired shape of the lobe of the array microphone at the processor; specifying a centerline of the plurality of microphone elements transverse to the desired steering vector based on the desired steering vector using the processor; selecting the subset based on the respective distances of the one or more subsets of the plurality of microphone elements to the centerline using the processor; and determining weights for the selected subset of the plurality of microphone elements using the processor, wherein the weights may be applied to the magnitude of the audio signal of the selected subset so that the shape of the one or more lobes is adjusted to the desired shape.

[0012] These and other embodiments and various arrangements and aspects will become apparent and more fully understood from the following detailed description and accompanying drawings, which set forth illustrative embodiments that are indicative of the various ways in which the principles of the invention may be employed. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a block diagram of an array microphone according to some embodiments.

[0014] Figure 2 is a schematic diagram of an array microphone including microphone elements according to some embodiments.

[0015] Figure 3 is a flow chart illustrating operations for adjusting the lobe shape of an array microphone in accordance with some embodiments.

[0016] Figure 4 is a flow chart illustrating operations for selecting a subset of microphone elements in an array microphone to adjust a lobe shape in accordance with some embodiments.

[0017] Figures 5A to 5F is a graph showing polar responses and magnitude weightings for various subsets of microphone elements according to some embodiments. DETAILED DESCRIPTION

[0018] The following description describes, illustrates and exemplifies one or more specific embodiments of the present invention based on the principles of the present invention. This description is not intended to limit the present invention to the embodiments described herein, but to explain and teach the principles of the present invention in such a way that a person of ordinary skill in the art can understand these principles and, with such understanding, can apply them to practice not only the embodiments described herein, but also other embodiments that can be conceived according to these principles. The scope of the present invention is intended to cover all such embodiments that can be attributed to the scope of the appended claims either literally or under the doctrine of equivalents.

[0019] It should be noted that in the description and drawings, similar or substantially similar elements may be marked with the same reference numerals. However, sometimes these elements may be marked with different numbers, such as in situations where such markings facilitate a clearer description. In addition, the drawings set forth herein are not necessarily drawn to scale, and in some examples may have been enlarged to more clearly depict certain features. Such markings and diagrammatic practices do not necessarily imply underlying substantive purposes. As described above, this specification is intended to be considered as a whole and to be interpreted and understood by a person of ordinary skill in the art according to the principles of the present invention as taught herein.

[0020] The array microphone system and method described herein can make it possible to adjust the shape of the lobe of the pickup pattern to provide more efficient and optimal coverage of the environment for sound capture. The array microphone may include multiple microphone elements, and a processor in communication with the microphone elements. The processor can shape one or more lobes by combining the audio signals received from the microphone elements, and each lobe can be associated with a steering vector. The processor can adjust the shape of the lobe in a direction independent of the steering vector by applying weights to the magnitude of the audio signals of a subset of the microphone elements. In this way, the user can have greater control over the geometry of the lobe of the array microphone to, for example, avoid unwanted noise and / or more efficiently cover audio sources within the environment.

[0021] Figure 1 1 is a block diagram of an array microphone 100 that can detect sounds from an audio source at various frequencies. The array microphone 100 can be utilized in, for example, a conference hall or meeting room where the audio source can be one or more speakers. Other sounds that can be undesirable may be present in the environment, such as noise from ventilation equipment, other personnel, audio / visual equipment, electronic devices, etc. In a typical case, the audio source can be sitting in a chair at a table, but other configurations and placements of the audio source are contemplated and possible.

[0022] The array microphone 100 can be placed on a table, podium, desktop, etc., so that sounds from an audio source, such as a speech spoken by a speaker, can be detected and captured. The array microphone 100 can include, for example, any number of microphone elements 102a, 102b, ..., 102zz, and can shape multiple pickup patterns so that sounds from an audio source can be detected and captured. Any appropriate number of microphone elements 102 is possible and contemplated.

[0023] Each of the microphone elements 102 in the array microphone 100 can detect sound and convert the sound into an analog audio signal. Components in the array microphone 100 (e.g., analog / digital converters, processors, and / or other components) can process the analog audio signals and ultimately generate one or more digital audio output signals. The digital audio output signals may comply with the Dante standard in some embodiments for transmitting audio via Ethernet, or may comply with another standard and / or transmission protocol. In an embodiment, each of the microphone elements 102 in the array microphone 11 can detect sound and convert the sound into a digital audio signal. The processor 150 in the array microphone 100 can shape one or more pickup patterns according to the audio signals of the microphone elements 102, and the processor 150 can generate a digital audio output signal 180 corresponding to each of the pickup patterns. The pickup pattern may consist of one or more lobes (e.g., a main lobe, a side lobe, and a rear lobe). In other embodiments, the microphone elements 102 in the array microphone 100 may output analog audio signals so that other components and devices (eg, processors, mixers, recorders, amplifiers, etc.) outside the array microphone 100 may process the analog audio signals.

[0024] The array microphone 100 may include microphone elements 102, a processor 150 in wired or wireless communication with the microphone elements 102, a database 160 in wired or wireless communication with the processor 150, and a user interface 170 in wired or wireless communication with the processor 150. These components are described in more detail below. The various components included in the array microphone 100 may be implemented using software that may be executed by one or more servers or computers (e.g., a computing device having a processor and a memory) and / or by hardware (e.g., discrete logic circuits, application specific integrated circuits (ASICs), programmable gate arrays (PGAs), field programmable gate arrays (FPGAs), etc.).

[0025] like Figure 2As depicted in the schematic diagram of , microphone elements 102 (represented by dots) may be arranged in concentric rings and / or nested in a harmonic manner. In some embodiments, microphone elements 102 may be arranged to be substantially symmetrical. In other embodiments, microphone elements 102 may be arranged asymmetrically or in another arrangement. In other embodiments, for example, microphone elements 102 may be arranged on a substrate, placed in a frame, or suspended individually. An embodiment of array microphone 100 is described in commonly assigned U.S. Pat. No. 9,565,493, the entire text of which is hereby incorporated herein by reference. In an embodiment, microphone element 102 may be a unidirectional microphone that is primarily sensitive in one direction. In other embodiments, microphone element 102 may have other directivity or polarity patterns, such as cardioid, subcardioid, or omnidirectional, as desired. Microphone element 102 may be any suitable type of transducer that can detect sound from an audio source and convert the sound into an electrical audio signal. In an embodiment, microphone element 102 may be a microelectromechanical system (MEMS) microphone. In other embodiments, the microphone element 102 may be a condenser microphone, a balanced armature microphone, an electret microphone, a dynamic microphone, and / or other types of microphones.

[0026] Figure 2 The microphone elements 102 depicted in FIG. 1 may be positioned and configured to cover a specific frequency band within a range of operating frequencies. Figure 2 , there may be multiple microphone elements 102 positioned and configured to cover the upper frequencies. Other microphone elements (not shown) may be positioned and configured to cover other specific frequency bands. As described in more detail below, in embodiments, microphone elements 102 may be selectively divided into segments for the purpose of lobe shaping. In other embodiments, microphone elements 102 may be selected on a per-microphone element basis for the purpose of lobe shaping.

[0027] Figure 3 An embodiment of a process 300 for adjusting the lobe shape of an array microphone 100 is shown in FIG. The process 300 may be used to adjust the lobe shape of an array microphone 100 from Figure 1 The array microphone 100 shown in FIG. 1 outputs a beamformed output signal 180 corresponding to a pickup pattern having an adjusted lobe shape. One or more processors 150 and / or other processing components (e.g., analog / digital converters, encryption chips, etc.) within or outside the microphone may perform any, some, or all of the steps of process 300. One or more other types of components (e.g., memory, input and / or output devices, transmitters, receivers, buffers, drivers, discrete components, etc.) may also be used in conjunction with the processor 150 and / or other processing components to perform any, some, or all of the steps of process 300.

[0028] At step 302, a desired steering vector and a desired shape of a lobe may be received at the processor 150. In an embodiment, the desired steering vector and the desired shape of the lobe may be determined programmatically or algorithmically using an automatic decision scheme. In other embodiments, a user may input the desired steering vector and the desired shape at a user interface 170 that communicates with the processor 150. In an embodiment, the user interface 170 may be a dedicated electronic device (e.g., a touch screen, a keypad, etc.) or a stand-alone electronic device (e.g., a smart phone, a tablet computer, a computer, etc.). In an embodiment, the user interface 170 may display a drawing of the lobe to help the user configure the array microphone 100, for example by showing the lobe emitted from the array microphone 100 under the current steering vector and / or the desired steering vector with the current lobe shape and / or the desired lobe shape.

[0029] The desired steering vector may be expressed as a specific three-dimensional coordinate relative to the position of the array microphone 100, such as in Cartesian coordinates (i.e., x, y, z), or in spherical coordinates (i.e., radial distance r, polar angle θ (theta), azimuth angle For example, the desired lobe shape may be input or determined as a gradient (e.g., narrow, medium, wide, etc.) or as an angle of field of view in one or more dimensions (e.g., degrees, change in degrees, percentage change, etc.).

[0030] At step 304, processor 150 may receive an audio signal from microphone element 102. Microphone element 102 may be, for example, Figure 2 , or in another other suitable arrangement. At step 306, one or more lobes of the pickup pattern may be shaped by processor 150 by combining the audio signals received from microphone elements 102. The lobes may be shaped using any suitable beamforming algorithm. For example, the lobes may be shaped to correspond to the desired steering vector received at step 302.

[0031] Adjustments to the lobe shape may be performed at steps 308 and 310. Specifically, at step 308, processor 150 may determine (1) a subset of microphone elements 102 and (2) weights to be applied to audio signals from microphone elements 102 that will be used to implement the desired lobe shape adjustment. In some embodiments, processor 150 may determine the subset of microphone elements 102 and the weights in real time for a particular lobe shape adjustment, such as by calculating the weights using a closed-form solution. Figure 44. The process 400 shown in FIG. 4 discusses one embodiment of a method for selecting a subset of microphone elements 102 and weights. In other embodiments, for a particular lobe shape adjustment, processor 150 may retrieve from database 160 a list representing a subset of microphone elements 102 and weights to be applied to audio signals from microphone elements 102. In this embodiment, database 160 may include multiple lists and weights for various lobe shape adjustments. For example, database 160 may have such lists and weights preloaded in a lookup table. In other embodiments, the selection of a subset of microphone elements 102 and weights may be based on real-time adaptive beamforming.

[0032] In some embodiments, a subset of microphone elements 102 may be selected on a per-microphone element basis. In other embodiments, for example Figure 2 As shown in FIG. 1 , a subset of microphone elements 102 may be selected by segmenting them. For example, a subset of microphone elements 102 may be selected based on a centerline 200 and segments 202, 204, and 206 that are mirrored about the centerline 200. Figure 2 The number and type of segments may vary in other embodiments of the array of microphone elements 102. Figure 2 , a first subset of microphone elements 102 may be microphone elements 102 arranged generally along a centerline 200. A second subset of microphone elements 102 may be microphone elements 102 generally within an inner mirror segment 202 adjacent to the centerline 200. A third subset of microphone elements 102 may be microphone elements 102 generally within an intermediate mirror segment 204 adjacent to the inner mirror segment 202. A fourth subset of microphone elements 102 may be microphone elements 102 generally within an outer mirror segment 206 adjacent to the intermediate mirror segment 204. For a particular lobe shape adjustment, none, some, or all of the microphone elements 102 in segments 202, 204, and 206 may be selected.

[0033] At step 310, weights may be applied to the magnitude of the audio signal of a subset of microphone elements 102 in order to adjust the shape of the lobe to a desired lobe shape. The lobe shape may be adjusted in a direction independent of the steering vector. For example, the lobe may be stretched wider while maintaining the steering vector of the lobe. In some embodiments, the weights applied may be based on the distance of the microphone elements 102 in the selected subset from the centerline 200. In these embodiments, the centerline 200 may be transverse to the steering vector of the lobe. For example, the weighting may be defined as a fractional magnitude scaling that is algorithmically determined based on a vector definition of the direction in which the lobe is stretched. This determination may be Gaussian, linear, or based on weighting factors derived on any number of functions. The beamformed output signal 180 from the microphone array 100 may correspond to a pickup pattern having a lobe with an adjusted shape achieved as a result of process 300.

[0034] Figures 5A to 5F Polar response graphs showing various combinations of subsets and weights of microphone elements 102 that may result from various lobe shape adjustments. Figures 5A to 5F , the polar response graphs represent portions of the polar response assuming axial symmetry about the 0° axis. Specifically, the plane of the microphone array 100 is the plane passing through 90° and 270°, and 0° is the direction of array steering. As noted in the legends of the figures, the two lines in each graph show fixed and variable lobe shapes. The fixed axis shows the behavior of the microphone array 100 when all microphone elements 102 are used at full magnitude. In contrast, the variable axis shows the behavior of the microphone array 100 at the same steering angle with magnitude weighting applied as indicated.

[0035] Figure 5A The lobes and their shapes are shown when no weighting is applied to any of the microphone elements 102 . Figure 5A The plot in can be considered as the baseline lobe before any lobe shape adjustment has been performed. Figure 5B 2 shows that when a subset of microphone elements 102 in the outer segment 206 has been selected to apply a 50% weight to the magnitude of the audio signal of the subset, the Figure 5A In this scenario, no weighting is applied to the microphone elements 102 in the centerline 200, the inner section 202, and the middle section 204.

[0036] Figure 5C 2 shows the difference between the values ​​of the audio signals of the subset when a subset of microphone elements 102 in the middle section 204 has been selected to apply a weight of 75% to the magnitude of the audio signals of the subset and a subset of microphone elements 102 in the outer section 206 has been selected to apply a weight of 25% to the magnitude of the audio signals of the subset. Figure 5BIn this scenario, no weighting is applied to the microphone elements 102 in the centerline 200 and the inner section 202. Figure 5D 2 shows that when a subset of microphone elements 102 in the middle section 204 has been selected to apply a 50% weight to the magnitude of the audio signal of the subset, there is a ratio of Figure 5C In this scenario, no weighting is applied to the microphone elements 102 in the centerline 200 and the inner section 202, and the microphone elements 102 in the outer section 206 are inactive.

[0037] Figure 5E 2 shows the difference between the values ​​of the microphone elements 102 in the middle section 204 and the values ​​of the microphone elements 102 in the inner section 202 when a 25% weight is applied to the magnitude of the audio signal of the subset and a 75% weight is applied to the magnitude of the audio signal of the subset. Figure 5D In this scenario, no weighting is applied to the microphone elements 102 in the centerline 200, and the microphone elements 102 in the outer section 206 are inactive. Fig. 5F 200 and 206. The example diagram shows the effect of having a ratio when only the microphone element 102 in the centerline 200 has been selected and no weighting is applied and the microphone elements 102 in the inner section 202, the middle section 204, and the outer section 206 are inactive. Figure 5E The lobes in the shape of the lobes are wider.

[0038] In some embodiments, Figure 4 The process 400 shown in Figure 3 4 ) determines a subset of microphone elements 102 selected when adjusting the lobe shape. One or more processors 150 and / or other processing components within or outside the microphone (e.g., analog-to-digital converters, encryption chips, etc.) may perform any, some, or all of the steps of process 400. Any, some, or all of the steps of process 400 may also be performed in conjunction with processor 150 and / or other processing components using one or more other types of components (e.g., memory, input and / or output devices, transmitters, receivers, buffers, drivers, discrete components, etc.).

[0039] At step 402, a desired steering vector and a desired shape of a lobe may be received at the processor 150. As described above, the desired steering vector and the desired shape may be determined programmatically in some embodiments, or may be input at a user interface 170 in communication with the processor 150 in other embodiments. At step 404, the processor 150 may specify a centerline of the microphone element 102 that is transverse to the desired steering vector. At step 406, one or more subsets of the microphone elements 102 may be selected for the purpose of lobe shape adjustment, wherein the subsets are selected based on the perpendicular distance of the subsets from the centerline specified at step 404. The subsets of the microphone elements 102 may be selected on a per-microphone element basis or by segmenting the microphone elements 102, as described above. In an embodiment, the selection of the subset of microphone elements 102 may be performed using a nearest neighbor search along the centerline. At step 408, a weight for each of the microphone elements 102 in the subset may be determined based on the distance of the microphone element 102 from the centerline specified at step 404.

[0040] Any process descriptions or blocks in the figures should be understood to represent modules, segments, or portions of code, which include one or more executable instructions for implementing specific logical functions or steps in the process, and alternative implementations are included within the scope of the embodiments of the present invention, in which functions may be performed out of the order from that shown or discussed (including substantially simultaneously or in reverse order, depending on the functionality involved), as will be understood by ordinary technicians in the field.

[0041] The present invention is intended to explain how to form and use various embodiments of the technology according to the present invention rather than to limit its true, intended and reasonable scope and spirit. The foregoing description is not intended to be exhaustive or limited to the precise form disclosed. Modifications and changes are possible in view of the above teachings. The embodiments are selected and described to provide the best explanation of the principles of the described technology and its practical application, and to enable ordinary technicians in the field to utilize the technology of the present invention in various embodiments and with various modifications suitable for the specific use considered. When interpreted according to the breadth reasonably, legally and fairly granted, as may be revised during the pendency of this patent application and all equivalents thereof, all such modifications and changes are within the scope of the embodiments as determined by the appended claims.

Claims

1. An array microphone, comprising: a plurality of microphone elements, each of the plurality of microphone elements being configured to detect sound and output an audio signal; as well as a processor in communication with the plurality of microphone elements, the processor being configured to: receiving a desired steering vector and a desired shape of a lobe of the array microphone; specifying, based on the desired steering vector, centerlines of the plurality of microphone elements that are transverse to the desired steering vector; selecting one or more subsets of the plurality of microphone elements based on designating one or more segments of the plurality of microphone elements as one or more subsets and based on respective distances of the subsets to the centerline, wherein the one or more segments are mirrored about the centerline; as well as Determining weights for the magnitude of each audio signal of one or more subsets of the plurality of microphone elements, wherein the determined weights are based on the distances of the microphone elements in the selected subset to the center line, wherein the weights are applied to the magnitude of each audio signal of the selected subset such that the shape of the lobe is adjusted to the desired shape, and wherein the adjustment of the shape of the lobe is in a direction independent of the desired steering vector. 2 . The array microphone of claim 1 , wherein the processor is further configured to automatically determine the desired steering vector and the desired shape. 3 . The array microphone of claim 1 , further comprising a user interface in communication with the processor, wherein the processor is further configured to receive the desired steering vector from the user interface.

4. The microphone array according to claim 1: It further includes a user interface in communication with said processor; in: The processor is further configured to receive the desired shape of the lobe from the user interface.

5. The microphone array according to claim 1: It further includes a database in communication with the processor, wherein the database includes a plurality of weights corresponding to different shapes of the lobe; in: The processor is further configured to retrieve the weights for the shapes of the lobes from the database.

6. The array microphone of claim 1, wherein the plurality of microphone elements are arranged in a number of concentric nested rings of different sizes, each ring comprising a subset of the plurality of microphone elements positioned at predetermined intervals along a circumference of the ring. The array microphone of claim 6 , wherein the concentric nested rings are rotationally offset from each other.

8. The array microphone of claim 6, wherein the rings are positioned at different radial distances from a center point of the substrate to form a nested configuration. 9 . The array microphone of claim 6 , wherein each of the rings forms a circle with a different diameter.

10. The array microphone of claim 9, wherein the diameter of each ring is determined based on a lowest operating frequency assigned to the subset of microphone elements included in the ring.

11. The array microphone of claim 6, wherein the ring of microphone elements is configured to cover a predetermined range of audio frequencies.

12. The array microphone of claim 1, wherein the plurality of microphone elements comprise micro-electromechanical system (MEMS) microphones.

13. A method of determining weights for a subset of a plurality of microphone elements in an array microphone using a processor for adjusting a shape of a lobe of the array microphone, the method comprising: receiving at the processor a desired steering vector and a desired shape of the lobe of the array microphone; specifying, using the processor, centerlines of the plurality of microphone elements transverse to the desired steering vector based on the desired steering vector; selecting, with the processor, one or more subsets of the plurality of microphone elements based on designating one or more segments of the plurality of microphone elements as one or more subsets and based on respective distances of the subsets to the centerline, wherein the one or more segments are mirrored about the centerline; and The weights for the selected subset of the plurality of microphone elements are determined using the processor, wherein the determined weights are based on distances of the microphone elements in the selected subset to the center line, wherein the weights are applied to the magnitude of each audio signal of the selected subset such that the shape of the lobe is adjusted to the desired shape, and wherein the adjustment of the shape of the lobe is in a direction independent of the desired steering vector.

14. The method of claim 13, wherein selecting the one or more subsets comprises performing a nearest neighbor search along the centerline to select the one or more subsets of the plurality of microphone elements.

15. The method according to claim 13, further comprising: receiving, at the processor, the audio signal from each of the plurality of microphone elements; and The lobe is shaped, using the processor, based on combining the audio signals, the lobe being associated with the desired steering vector.

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