WO2019229657A1

WO2019229657A1 - Directional multi channel adaptive beamforming loud-speaker system

Info

Publication number: WO2019229657A1
Application number: PCT/IB2019/054419
Authority: WO
Inventors: Alon Shalev
Original assignee: Acoustic Horizons Ltd.
Priority date: 2018-05-29
Filing date: 2019-05-28
Publication date: 2019-12-05

Abstract

A system and methods for spatial sound reproduction are herein provided. In one embodiment, the system includes a control unit operably connected to one or more directional speaker units, the directional speaker unit (DSU) comprising: a receiver for receiving one or more audio input signals from the control unit, the receiver being adapted to generate from the one or more audio signals, one or more pre-processed input signals; a multiple-input-multiple-output beam-former (MIMO-BF), adapted to input the one or more pre-processed input signals and to generate a plurality of digital audio output channels, so as to affect a plurality of spatial acoustic beams; and a transmitter for signal processing and acoustically transducing the plurality of digital audio output channels, using a plurality of respective digital to analog audio output channels.

Description

DIRECTIONAL MULTI CHANNEL ADAPTIVE BEAMFORMING

LOUD-SPEAKER SYSTEM

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of Provisional Patent Application 62/677,535, filed 29 May 2018, entitled“DIRECTIONAL MULTI CHANNEL ADAPTIVE

BEAMFORMING LOUD-SPEAKER SYSTEM”, which is incorporated in its entirety herein by reference.

FIELD OF THE INVENTION

[001] The present invention relates to acoustics, in particularly directed acoustics.

BACKGROUND OF THE INVENTION

[002] It is often desirable to direct sound, so that it will be loud when perceived at locations near an acoustic axis along a direction of sound propagation, and attenuated at other locations.

[003] For example, in public address systems it is often desirable to project sound outward from a stage or podium, but not to overwhelm people in the audience, yet to have the projected sound be loud enough to be heard in the rear portion of the auditorium, which may be quite extensive and located far from the stage. There are additional situations where directed sound would be desirable, some of which may not have been universally recognized by practitioners in the art of acoustics.

[004] It may often be desired to control the volume of a single audio stream in a given space, such that some regions would have a louder intensity and some, lower. Nonetheless, in many instances, not necessarily regions that are farther from a loudspeaker need to be quieter, and vice versa. Furthermore, in some instances, a region in space is desired to have a quieter intensity of sound, wherein regions partially or generally surrounding it, are desired to have a larger intensity of sound. For example, in a cafe, some of the clients may wish to hear ambient music at a reasonably discernible intensity, while, a particular table therebetween, in which a gentlemen proposes marriage, may prefer lower intensity music. A solution to this situation is difficult, if not impossible, to realize, using conventional loudspeaker systems.

[005] Furthermore, there may be instances, where different audio streams may need to be oriented differently in a given space. For example, within conventional supermarket walking passages, different commercials may be desired to be directed towards different spatial locations along such passages, such that, for example, nearby the pasta shelves, a different audio stream may need to be directed, relative to the spatial location adjacent the mayonnaise shelves, or the soft drinks locations. In that case, a desired loudspeaker system - to be most likely hung above the abovementioned supermarket passage - is desired to be able to spatially direct different audio streams towards different locations along that passage. Moreover, such a loudspeaker system may not only be desired to direct such different audio streams statically, as it may be required to continuously, or intermittently, adapt the orientation of each of the abovementioned audio streams, towards a visually tracked object, such as a person passing in such a passage, in accordance with specific visual cues, such as stalling nearby a certain shelf, or location along said passage, or, even, slowing down his velocity when passing nearby a certain location, possibly indicating possible interest in specific kinds of products, which subsequently, should be advertised to this person, i.e. "moving target". In summary, in accordance with a particular embodiment of the present invention, a plurality of wide-band audio streams, are desired to be directed - via a plurality of acoustic beams - towards different spatial directions, each possibly having different beam widths, volume and center beam direction, wherein such characteristics of each acoustic beam, may be adapted in real-time, in accordance with visual cues that are recorded in at least one video camera, which is integrated into said system.

SUMMARY OF THE INVENTION

[006] The present invention relates to acoustics, in particularly directed acoustics. More particularly, the invention concerns beam steering of a plurality of acoustic beams, wherein each acoustic beam is controlled as to its content, i.e. audio signal; as to its volume; and as to its spatial characteristics, such as the direction of the centerline of the main lobe (beam), including at least one half-power beam width of that acoustic beam.

[007] In accordance with embodiments of one aspect of the present invention, there is provided a system for directing an acoustic signal, as described below and defined in the claims.

[008] In some embodiments, the system uses a wide-band audio reproduction system.

[009] It should also be noted that in the most basic sense, the audio signal can considered as a plurality of audio sources, that is, a plurality of audio streams, each of which needs to be beamed (directed) to a particular spatial direction, and each possibly has a different beam width (that can be measured both in the lateral and pitch directions, that is, in the azimuth and elevation directions) and intensity (i.e. volume). In a particular case, the audio signal may be a single audio source, but each acoustic beam would have a different center-beam direction, beam width, and volume. In this particular case, one may assign difference volume levels to different locations in, say, a cafe, without actually playing different audio streams in the cafe.

[0010] In accordance with embodiments of the present system, there can be various approaches towards realizing beam steering. Phase-shift approaches are suitable for narrow band signals. Delay-and-sum are suitable for wide-band signals, which is the case in this disclosure. There are other, more complicated (and in most cases, iterative) algorithms to realize beam steering, either using autofocusing or other techniques that use minimization of co st- functions.

[0011] In some embodiments, the directions (beam steering) can be altered in real-time. Further, the respective directions of the respective various beams - each possibly containing a different audio signal - may be altered in real-time according to a camera and algorithm that is configured to track objects and/or people, and direct each audio/acoustic beam there- toward.

[0012] In accordance with embodiments of another aspect of the present invention, there is provided a method for directing an acoustic signal, as understood from the description below.

BRIEF DESCRIPTION OF THE DRAWINGS [0013] The principles and operation of the system, apparatus, and method according to the present invention may be better understood with reference to the drawings, and the following description, it being understood that these drawings are given for illustrative purposes only and are not meant to be limiting, wherein:

[0014] Figs. 1 and 2 are block diagrams of a system for spatial sound reproduction, in accordance with embodiments of the present invention, depicting different configurations thereof;

[0015] Fig. 3 is a block diagram of an exemplary audio channel of the present system;

[0016] Fig. 4 is a schematic depiction of a control unit, operably connected to a plurality of directional speaker units, in accordance with embodiments of the present system;

[0017] Fig. 5 is a schematic representation of various audio sources that may constitute an audio channel, such as presented in Fig. 3;

[0018] Fig. 6 is a schematic depiction of two major categories of client inputs to the present system;

[0019] Figs. 7-10 are schematic depictions of exemplary deployments of directional speaker units of the present system;

[0020] Fig. 11 is a schematic depiction of an exemplary floor plan utilizing a single 2D directional speaker unit of the present system;

[0021] Fig. 12 is a schematic depiction of an exemplary floor plan utilizing a two 2D directional speaker unit of the present system;

[0022] Figs. 13-15 are schematic depictions of a store with exemplary configurations of several 2D directional speaker units of the present system; and

[0023] Fig. 16 is a schematic depiction of a single 2D directional speaker unit of the present system, positioned in a public space.

[0024] It will be appreciated that for simplicity and clarity of illustration, elements shown in the drawings have not necessarily been drawn to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for clarity. Further, where considered appropriate, reference numerals may be repeated among the drawings to indicate corresponding or analogous elements throughout the serial views.

DETAILED DESCRIPTION OF EMBODIMENTS

[0025] The following description is presented to enable one of ordinary skill in the art to make and use the invention as provided in the context of a particular application and its requirements. Various modifications to the described embodiments will be apparent to those with skill in the art, and the general principles defined herein may be applied to other embodiments. Therefore, the present invention is not intended to be limited to the particular embodiments shown and described, but is to be accorded the widest scope consistent with the principles and features herein disclosed. In other instances, well-known methods, procedures, and components have not been described in detail so as not to obscure the present invention.

[0026] According to embodiments of the present invention, a system for selected and/or customized spatial sound reproduction and/or broadcasting is provided.

[0027] Fig. 1 shows an embodiment of a loudspeaker system of the present invention, for spatial sound reproduction. The speaker system includes a control unit connected to one or more directional speaker units, wherein a loudspeaker group includes a single loudspeaker driver. The speaker system includes a control unit connected to one or more directional speaker units (DSU). The directional speaker units (DSU) may include: a receiver stage for receiving one or more audio input signals from the control unit. The system further includes a receiver adapted to generate, from the one or more audio signals, one or more pre-processed input signals; a multiple-input-multiple-output beam-former (MIMO-BF), adapted to input the one or more pre-processed input signals and to generate a plurality of digital audio output channels (DAOC), so as to affect a plurality of spatial acoustic beams; a transmitter stage, for signal processing and acoustically transducing the plurality of digital audio output channels (DAOC), using a plurality of respective digital to analog audio output channels (DAAOC).

[0028] The channel in the digital to analog audio output channels (DAAOC) may include: a digital to analog converter (DAC); a post-MIMO filter; an analog amplifier; and a loudspeaker group, including one or more loudspeaker drivers. Further, the control unit may include: a central processing unit; an interface to one or more external input audio signals; and a man- machine interface.

[0029] Fig. 2 shows an embodiment of the loudspeaker system, which is similar to Fig. 1, however each loudspeaker group includes three loudspeaker drivers.

[0030] Fig. 3 shows an audio channel including examples of the signals of a plurality of microphones, a plurality of locally or externally stored music files, a plurality of web streaming audio channels, a plurality of physically connected auxiliary channels, a plurality of wirelessly transmitted audio signals and a plurality of other physically connected channels, such as, e.g. CD players, turntable players, etc.

[0031] Fig. 4 shows a control unit connected to a plurality of directional speaker units. As can be seen, directional speaker units #1, #2 and #3 are constructed as 2D loudspeaker arrays, and directional speaker units #4 and #5 are constructed as 1D loudspeaker arrays.

[0032] Fig. 5 shows various exemplary audio sources that may constitute an audio channel, for example those illustrated in Fig. 3.

[0033] Fig. 6 shows a client / system interface illustrating two major categories of client inputs to the system. As can be seen, audio content input can be via stored audio content provided by the client, for example, wirelessly, physically connected, or streamed to the control unit. Alternatively, the client may select a desired audio channel from a web-based application, which channel would be streamed to the acoustic beam that is directed at an end user.

[0034] As can be further seen, control content input is depicted, whereby, (a) the client may switch between either their personal, or the audio content provided by the system; (b) the client may select from a list of audio channels provided by the system; (c) the client may increase or lower the audio volume level; (d) the client may turn on or off a commercial advertisement mode; (e) the client may turn on or off a body gesture mode.

[0035] Fig. 7 shows a floor plan exemplified by a small sized cafe, with two 1D (i.e. line array) directional speaker units (DSU), denoted by "A" and "B". In this example, DSU“A” generates two spatial acoustic beams, marked by "1" and "2"; and DSU“B” generates one spatial acoustic beam, marked by "3". Regions where only a single spatial acoustic beam is effective, is marked by "1" or "2" or "3". Other regions, where more than a single spatial acoustic beam is effective, is marked by "1+2" or "2+3". Note also that the relative positioning of the DSUs (distance there-between and also relative to the tables in the cafe), determine what type of spatial angle - in this case only in one direction, i.e. azimuth - should be covered by each of the DSU. This is why, for example, there's a single beam being transmitted from DSU "B" and its central angle is approximately 0 degrees, and its angular width is approx. 60 degrees, whereas, DSU "A" needs to have one beam centered at about 345 degrees (i.e.“10:30 o'clock”) and another acoustic beam centered at about 30 degrees (i.e.“1 o'clock”), and each beam width is also approx. 60 degrees.

[0036] Fig. 8 shows the same floor plan as in Fig. 7, but in this example, three 1D directional speaker units (DSU) are disposed in this space, denoted by "A", "B" and "C". It can be seen that by adding a DSU, the regions of overlap (1+2 and 2+3) between the different spatial acoustic beams are reduced, without compromising the overall coverage of all seating areas in the floor plan. Note that positioning of the DSUs is something that is done at installation, while the tables may be moved around.

[0037] Fig. 9 shows an alternative arrangement of the two 1D DSUs shown in Fig. 7. As can be seen, changing the absolute, and/or relative positioning of the DSUs affects a change in both the spatial coverage of the spatial acoustic beam, as well as the overlap therebetween. Note that the lower DSU has 2 beam lobes. In this particular embodiment, it makes sense that the same audio stream would be transmitted through all of the acoustic beams in all of the DSUs in the cafe, since it might be annoying for the clients to hear two music streams, even at different volume levels. Fig. 9 emphasizes the option of having more than a single acoustic beam, because this is a particular feature of the present invention. Thus, for example, clients sitting in the four tables that are "covered" by acoustic beam "3", can request a different volume level than clients sitting at tables covered by acoustic beam "2", as each beam can have an independent volume level. Furthermore, in the embodiments shown in the "supermarket" examples, not only would each of the streams have possibly different volume levels, but they could have different contents, e.g. one would have a commercial for pasta, and the other, for condiments. [0038] Fig. 10 shows an additional arrangement of DSUs, consisting of the three 1D DSUs, such as in Fig. 8, but at different positions.

[0039] Fig. 11 shows a speaker unit configuration utilizing a single 2D DSU, which affects 2D beam steering. In a 2D DSU, the acoustic beam's angle is modifiable in two dimensions, that is, yaw and pitch (azimuth/elevation, or x/y). Essentially this is a "delay and sum" beamformer, realizable both on the columns and on the rows of the loudspeaker elements in the array. The main difference in the configuration here is that the DSU needs to be hung from the ceiling, so that its two dimensions would be able to span both X and Y coordinates of the cafe's floor. In this configuration, a single 2D DSU, which has 2D beam steering capability, directs individual spatial acoustic beams to each of the individual seating locations in the cafe, with hardly any or minimal overlap therebetween, nor any "holes" in the acoustic coverage.

[0040] Fig. 12 shows a DSU configuration similar to that of Fig. 11, however using two 2D DSUs, whereby each DSU may utilize a lower number of spatial acoustic beams, and each beam may have less aggressive requirements, such as low beam width, and the like. An advantage of having "narrow beams" is that this provides a higher spatial resolution. That is, for example, this could potentially allow the restaurant administrator to individually control the volume level, perceived at each of the individual tables, as opposed to being able to modify the volume levels only of larger floor regions in the restaurant.

[0041] Figs. 13, 14 and 15 depict various configurations and arrangements of DSUs above supermarket aisles, so as to provide individual spatial acoustic beams. Note that in the context of the present invention ID and 2D DSUs relate to the degree of freedom of the angular control of the DSU. That is, if the DSU can steer the center of the beam in 2D, both sideways and up/down, then it would be defined as 2D. Otherwise, in case the DSU can only steer the center of each of its plurality of acoustic beams in a single direction, it would be defined as a ID. However, in order to have a relatively narrow beam width in the non- steered direction, even ID DSUs may utilize a two dimensional array of loudspeaker elements, such as depicted in Fig. 2. Note that Fig. 2 shows that each triplet of loudspeaker elements in a group, are connected to an identical amplifier, hence, they receive the same audio input, hence, the beam that each triplet for, cannot be steered. [0042] A reason for desiring to reduce the acoustic beam width, for example, in the supermarket application, is that in case of a 1D array of loudspeakers, the acoustic beam - thought steerable in the direction of the passage, will "spill over" to adjacent passages on the right and left of the desired passage. By placing a plurality of loudspeaker elements, being connected to essentially the same audio signal, the beam width in the lateral direction is narrowed, hence, reducing the spill-over of audio commercials that are intended for a particular passage, to adjacent passages. The usage of a 2D DSU may help to reduce the lateral beam width of the DSU, so that the spatial acoustic beam would have minimal coverage over adjacent aisles, over which it is not positioned or aimed. Namely, in some embodiments, the 2D DSUs utilize a 2D array of loudspeaker drivers, wherein each lateral group of loudspeaker drivers belongs to the same digital to analog audio output channels (DAAOC). Clearly, in such embodiments, the DSUs would include a camera unit, configured to observe, identify, classify and track, preferably in real-time, customers who pass through the supermarket aisles, and in accordance to the identified and classified objects or other user identifiers, and the locations of their respective movement dynamics, and shopping-related information (e.g. at which counters they halt, to which counters they send out their arms, etc.), adapt a commercial advertisement content.

[0043] Fig. 16 schematically depicts a single 2D DSU positioned in a public-space. As can be seen, the DSUs include a camera unit, which allows observing, identifying, classifying and tracking, preferably in real-time, the people passing by, and in accordance with such identification and classification, steers individual spatial acoustic beams toward individuals or groups, containing personalized audio content such as a commercial advertisement, public safety information, transportation safety information, weather information, or any other type of audio.

[0044] In some embodiments, the receiver includes a finite input response (FIR) filter, per each audio input signal.

[0045] In some embodiments, the post-MIMO filter includes an analog filter, which is adapted to receive an analog output of the DAC of the DAAOC.

[0046] In some embodiments, the post-MIMO filter includes a digital filter, which is adapted to receive an output of its respective audio channel in the MIMO-BF. [0047] In some embodiments, respective loudspeaker drivers are connected in parallel.

[0048] In some embodiments, respective loudspeaker drivers are connected in series.

[0049] In some embodiments, respective loudspeaker drivers are connected in a mixed series and/or parallel mode.

[0050] In some embodiments, the man-machine interface includes an administrator interface.

[0051] In some embodiments, the man-machine interface includes a client interface.

[0052] In some embodiments, the directional speaker units (DSU) further include one or more camera unit(s), where the camera unit is adapted to provide a streaming video signal to the control unit.

[0053] In some embodiments, the system includes an interface to one or more external input audio signals, which includes an interface to an external microphone channel.

[0054] In some embodiments, the interface to one or more external input audio signals includes an interface to an external line channel.

[0055] In some embodiments, the interface to one or more external input audio signals includes an interface to an external wireless channel.

[0056] In some embodiments, the wireless channel includes a radio frequency (RF) channel.

[0057] In some embodiments, the wireless channel includes a blue-tooth (BT) channel.

[0058] In some embodiments, the interface to one or more external input audio signals includes an interface to a digital media.

[0059] In some embodiments, the digital media includes an optical disk drive.

[0060] In some embodiments, the digital media includes a hard disk storage device.

[0061] In some embodiments, the digital media includes a solid state storage device.

[0062] In some embodiments, the interface to one or more audio signals includes an interface to a web streamed audio channel.

[0063] In some embodiments, the control unit is adapted to process a streaming video signal, thereby identifying one of a plurality of bodily gesture inputs, and in response thereto, affect a characteristic of either a receiver, a MIMO-BF or a transmitter. [0064] In some embodiments, the streaming video signal processing is adapted to cause an increase and/or decrease in the intensity of the spatial acoustic beam.

[0065] In some embodiments, the streaming video signal processing is adapted to cause muting and/or unmuting of the spatial acoustic beam.

[0066] In some embodiments, the streaming video signal processing is adapted to cause pausing and/or unpausing of an audio stream in the spatial acoustic beam.

[0067] In some embodiments, the transmitter includes ten or more loudspeaker drivers.

[0068] In some embodiments, the transmitter includes sixteen or more loudspeaker drivers.

[0069] In some embodiments, the loudspeaker group includes three or more loudspeaker drivers.

[0070] In some embodiments, the transmitter includes ten or more digital to analog audio output channels (DAAOC).

[0071] In some embodiments, the transmitter includes 16 or more digital to analog audio output channels (DAAOC).

[0072] In some embodiments, the loudspeaker groups are substantially disposed along a first spatial dimension defining an array line, and the plurality of spatial acoustic beams being generated by the multiple-input-multiple-output beam-former (MIMO-BF) stage are substantially steerable in one dimension within a solid angle along a plane being perpendicular to the array line.

[0073] In some embodiments, the one spatial dimension includes a straight line.

[0074] In some embodiments, the loudspeaker groups are substantially disposed along a first and a second spatial dimension, thereby defining an array surface, and the plurality of spatial acoustic beams being generated by the multiple-input-multiple-output beam-former (MIMO- BF) are substantially steerable in two dimensions within a solid angle that is substantially centered around a vector being perpendicular to the array surface.

[0075] In some embodiments, the array surface includes a plane.

[0076] In some embodiments, the array surface includes a curved surface, whose curvature radius exceeds 3 times the greater of the two dimensions of the array surface. [0077] In some embodiments, the administrator interface is adapted to allow the administrator the following functionality: graphically represent a spatial description of a target space; position the one or more directional speaker units (DSU) within the target space; define a centerline direction and/or a beam width in at least a first dimension and optionally a second dimension per the plurality of spatial acoustic beams of the one or more directional speaker unit (DSU); select one of the audio input signals for each of the spatial acoustic beams, or a plurality thereof; select whether a body gesture identification mode is active or inactive, for each of the spatial acoustic beams, or a plurality thereof; select for each of the spatial acoustic beams, or a plurality thereof, whether the advertisement mode would be activated or not; define a volume level for each the spatial acoustic beams, or a plurality thereof; visualize a graphical representation of a spatial coverage of the target space by the plurality of spatial acoustic beams; and visualize a graphical representation of spatial overlap between any two or more of the plurality of spatial acoustic beams.

[0078] In some embodiments, the positioning of one or more directional speaker units (DSU) is manually positioned by an administrator.

[0079] In some embodiments, the control unit is adapted to automatically position one or more directional speaker unit (DSU).

[0080] In some embodiments, the automatic positioning includes affecting the automatically positioning in accordance with a cost function, which is adapted to sum a solid angle overlap between a subgroup of the plurality of spatial acoustic beams.

[0081] In some embodiments, the solid angle overlap is weighted by the energy contained in each two or more overlapping spatial acoustic beams.

[0082] In some embodiments, the administrator interface is further adapted to allow the administrator the functionality to orient the one or more directional speaker unit (DSU) within the target space.

[0083] In some embodiments, the administrator interface is further adapted to allow the administrator the functionality to affect a calibration of the system and the calibration includes providing a microphone and connecting it with the control unit, wherein the control unit is adapted to measure via the microphone, characteristics of a synthetic audio calibration signal, the audio calibration signal being generated by the control unit.

[0084] In some embodiments, the client interface is adapted to allow the client the following functionality: select one of the audio input signals for a spatial acoustic beam that is spatially directed substantially in the direction of the client; define a volume level for the spatial acoustic beams that is spatially directed substantially at the direction of the client; select for the spatial acoustic beams that are spatially directed substantially at a direction of the client, whether advertisement mode would be activated or not; and select whether the body gesture identification mode is active or inactive, for the spatial acoustic beams that are spatially directed substantially in the direction of the client.

[0085] In some embodiments, the multiple-input-multiple-output beam-former (MIMO-BF) stage is adapted to spatially steer the acoustic beam towards a desired spatial direction.

[0086] In some embodiments, the multiple-input-multiple-output beam-former (MIMO-BF) is adapted to set a half-power beam width of the acoustic beam to a first desired value in at least a first spatial dimension.

[0087] In some embodiments, the multiple-input-multiple-output beam-former (MIMO-BF) is further adapted to set a half-power beam width of the acoustic beam to a second desired value in at least a second spatial dimension.

[0088] In some embodiments, the multiple-input-multiple-output beam-former (MIMO-BF) is adapted to spatially focus the acoustic beam at a desired distance from the directional speaker unit towards a desired spatial direction.

[0089] In some embodiments, the desired spatial direction is derived via the streaming video signal.

[0090] In some embodiments, the desired distance is calculated by the control unit, based on the streaming video signal from a plurality of camera units, the camera units disposed over respective directional speaker units (DSU).

[0091] In some embodiments, the administrator interface is further adapted to allow the administrator the functionality of defining the desired spatial direction. [0092] In some embodiments, the administrator interface is further adapted to allow the administrator the functionality of defining the half-power beam width in a first spatial dimension.

[0093] In some embodiments, the administrator interface is further adapted to allow the administrator the functionality of defining the half-power beam width in a second spatial dimension.

[0094] In some embodiments, the administrator interface is further adapted to allow the administrator the functionality of defining the desired distance.

[0095] In some embodiments, the multiple-input-multiple-output beam-former (MIMO-BF) is a delay and sum beamformer.

[0096] In some embodiments, the plurality of loudspeaker drivers within their respective digital to analog audio output channels (DAAOC) includes a one dimensional loudspeaker array.

[0097] In some embodiments, the loudspeaker drivers within the one dimensional loudspeaker array are uniformly spaced therebetween.

[0098] In some embodiments, the plurality of loudspeaker drivers within their respective digital to analog audio output channels (DAAOC) include a two-dimensional loudspeaker array.

[0099] In some embodiments, the loudspeaker drivers within the two-dimensional loudspeaker array are uniformly spaced therebetween in a first dimension, and differently uniformly spaced therebetween in a second dimension.

[00100] In some embodiments, the loudspeaker array is a sparse array.

[00101] In some embodiments, the amount of sparsity in the sparse array exceeds 25 percent.

[00102] In some embodiments, the amount of sparsity in the sparse array exceeds 50 percent.

[00103] In some embodiments, the amount of sparsity in the sparse array exceeds 75 percent. [00104] In some embodiments, the control unit is adapted to control the multiple-input- multiple-output beam-former (MIMO-BF), thereby spatially directing one or more the spatial acoustic beams in the direction of respective one or more visual objects, the object being identified by the control unit within the streaming video signal.

[00105] In some embodiments, the visual object is tracked by the control unit within the streaming video signal.

[00106] In some embodiments, the spatially directing of the one or more the spatial acoustic beams is performed at a rate that exceeds 0.5 hertz.

[00107] In some embodiments, the spatially directing of the one or more the spatial acoustic beams is performed at a rate exceeds 2 hertz.

[00108] In some embodiments, the visual object is identified by the control unit within the streaming video signal.

[00109] In some embodiments, the control unit is adapted to identify the visual object by categorizing it to belong to one of a predefined set of different object classes.

[00110] In some embodiments, the predefined set of different object classes includes any one of the following list: human being(s), animal(s) and transportation vehicle(s).

[00111] In some embodiments, the human being includes a baby, toddler, kid, teen ager, young person, adult person, middle-aged person and an old-aged person.

[00112] In some embodiments, the animal includes any one of the following list: a cat, a dog, a pig, a bird and a snake.

[00113] In some embodiments, the human being may be a male and/or female.

[00114] In some embodiments, the control unit is further adapted to select the audio input signal in accordance with the identified object class.

[00115] In some embodiments, the audio input signal includes a commercial advertisement.

[00116] In some embodiments, the audio input signal includes traffic safety information. [00117] In some embodiments, the audio input signal includes weather related information.

[00118] The foregoing description of the embodiments of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. It should be appreciated by persons skilled in the art that many modifications, variations, substitutions, changes, and equivalents are possible in light of the above teaching. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the scope of the invention.

Claims

1. A system for spatial sound reproduction, comprising:

a control unit operably connected to one or more directional speaker units, the directional speaker unit (DSU) comprising:

a receiver for receiving one or more audio input signals from the control unit, the receiver being adapted to generate from the one or more audio signals, one or more pre- processed input signals;

a multiple-input-multiple-output beam-former (MIMO-BF), adapted to input the one or more pre-processed input signals and to generate a plurality of digital audio output channels, so as to affect a plurality of spatial acoustic beams;

a transmitter for signal processing and acoustically transducing the plurality of digital audio output channels, using a plurality of respective digital to analog audio output channels, wherein the channel in the digital to analog audio output channels comprises:

a digital to analog converter;

a post-MIMO filter;

an analog amplifier; and

a loudspeaker group, comprising one or more loudspeaker drivers, the control unit comprising:

a central processing unit;

an interface to one or more external input audio signals ; and

a man- machine interface.

2. The system of claim 1, further comprising an administrator interface adapted to allow the administrator the following functionalities:

graphically represent a spatial description of a target space;

position the one or more directional speaker unit within the target space;

define a centerline direction and/or a beam width in at least a first and optionally a second dimension in relation to the plurality of spatial acoustic beams, in relation to the one or more directional speaker units;

select one of the audio input signals for each of the spatial acoustic beams, or a plurality thereof; select whether a body gesture identification mode is active or inactive, for each of the spatial acoustic beams, or a plurality thereof;

select for each of the spatial acoustic beams, or a plurality thereof, whether an advertisement mode would be activated or not;

define a volume level for each the spatial acoustic beams, or a plurality thereof;

visualize a graphical representation of a spatial coverage of the target space via the plurality of spatial acoustic beams;

visualize a graphical representation of a spatial overlap between any two or more of the plurality of spatial acoustic beams.

3. The system of claim 2, wherein the administrator interface is further adapted to allow the administrator the functionality to affect a calibration of the apparatus, the calibration comprising providing a microphone and connecting it with the control unit wherein the control unit is adapted to measure via the microphone, characteristics of a synthetic audio calibration signal, the audio calibration signal being generated by the control unit.

4. The system of claim 3, further comprising a client interface adapted to allow the client the following functionalities:

select one of the audio input signals for one or more spatial acoustic beams that is spatially directed substantially at a direction of the client;

define a volume level for the spatial acoustic beams that is spatially directed substantially at a direction of the client;

select for the spatial acoustic beams that are spatially directed substantially at the direction of the client, whether advertisement mode would be activated or not; and

select whether the body gesture identification mode is active or inactive, for the spatial acoustic beams that are spatially directed substantially at a direction of the client.

5. The system of claim 1, wherein the control unit is adapted to control the multiple- input-multiple-output beam-former (MIMO-BF), thereby spatially directing one or more the spatial acoustic beams in the direction of respective one or more visual objects, the visual objects being identified by the control unit within a streaming video signal.

6. The system of claim 1, configured wherein the directions of one or more of the spatial acoustic beams is alterable in real-time.

7. The system of claim 6, configured wherein the directions of the spatial acoustic beams each comprise a different audio signal.

8. The system of claim 6, configured wherein the directions of the spatial acoustic beams are alterable in real-time according to a camera and algorithm, which is configured to track objects and/or people, and to direct each audio/acoustic beam there-toward.

9. A method for spatial sound reproduction, comprising:

connecting a control unit operably to one or more directional speaker units (DSU); receiving one or more audio input signals from the control unit, by a receiver adapted to generate from the one or more audio signals, one or more pre-processed input signals; inputting the one or more pre-processed input signals and generating a plurality of digital audio output channels, using a multiple-input-multiple-output beam-former (MIMO- BF) adapted to affect a plurality of spatial acoustic beams; and

processing signals and acoustically transducing the plurality of digital audio output channels, using a plurality of respective digital to analog audio output channels, by a transmitter.