WO2011139772A1

WO2011139772A1 - Sound wave modification

Info

Publication number: WO2011139772A1
Application number: PCT/US2011/034142
Authority: WO
Inventors: James Fairey
Original assignee: James Fairey
Priority date: 2010-04-27
Filing date: 2011-04-27
Publication date: 2011-11-10

Abstract

A headset configured to modify a sound wave is disclosed herein. According to one aspect of the presently disclosed subject matter, the headset receives a sound wave and information about the sound wave, modifies the sound wave based upon location information of the source of the sound wave, and plays the sound wave to assist the user of the headset in determining the location of the source of the sound wave. In one example, the sound wave is modified by modifying the phase shift and frequency gain adjustment.

Description

SOUND WAVE MODIFICATION

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Patent Application No. 61/328,342, filed 27 April 2010, and entitled "Sound Wave Modification"; U.S. Provisional Patent Application No. 61/388,220, filed 30 September 2010, and entitled, "Device for Sound Wave Modification"; and U.S. Provisional Patent Application No. 61/413,204, filed 12 November 2010, and entitled "Location Enabled Headset"; which are incorporated by reference as if set forth herein in their entireties.

TECHNICAL FIELD

The presently disclosed subject matter relates generally to sound wave modification and playback devices.

BACKGROUND

When playing back sound, whether it be from a headset with two speakers (a left and right earpiece) or from a home stereo with 7.1 surround sound capabilities, a desired effect is to create a "rich" or immersive feel to the music. For systems that use more than two speakers, this is often achieved by separating the sound into various channels and porting those channels to a particular speaker. For example, in a 5.1 surround sound system, there are 6 speakers, a center speaker, a sub woofer, two front left and right speakers and two rear left and right speakers. Thus, when the listener is sitting in an appropriate location and the speakers are properly aligned and calibrated, the listener, instead of hearing mere left and right sounds will experience a surround sound effect. The sounds will seemingly approach the listener from the front and rear left and right as well as the center. The sound location of a current art surround sound system uses the locations of multiple speakers to create an immersive or surround sound.

SUMMARY

In accordance with an aspect of the presently disclosed subject matter, ways in which sound waves may be modified and played back are disclosed. In one exemplary embodiment of the present invention, sound waves are modified using a device to increase or create the immersive feel of the sound wave. That is, the sound wave is modified to simulate surround

2273502vl _ \ _ sound or three dimensional input. Although the sound wave may be most appreciated when used with a headset or a device having only two speakers (a left and right channel), the presently disclosed subject matter may also be used, and is within the scope of the present invention, with a device having any number of speakers. Further, although the following description is applied to a sound signal for playback having a left and right channel, it is contemplated and should be understood to be within the scope of the presently disclosed subject matter that the same modification may be applied to a sound signal having more than two channels, whether they are played back using a two speaker system or more than two speaker system.

According to an embodiment of the presently disclosed subject matter, a device is configured to modify a sound wave. The device is configured with a first control that modifies the gain of the sound wave at various frequencies as well as a second control (which may incorporated into the first control or used as a separate control) that modifies the gain of the sound wave at various frequencies. To that effect, a sound signal having a left and right channel may be modified in at least two ways to generate a surround or three dimensional sounds to the listener. In one process for a particular sound having a left and right channel to at least be partially played back in a left and right speaker, a sound event in the left channel is time shifted, i.e. offset or phase shifted, from the same sound event in the right signal. This may also be termed phase shifting. In another process, the gains for various frequencies of the sound event for the left and right channels are adjusted so that one channel has a different gain the other channel(s). This may be termed differential frequency adjustment. In a still further process, the left and right channels (or other channels if using more than two speakers) are combined for playback. A sound event may include, but is not limited to, a sound that has been recorded from a similar event. For example, an explosion may be a sound event. It should be understood that a portion or the entire sound event may be phase shifted as well as a portion or all of the sound event may be differential frequency adjustment.

In accordance with an aspect of the presently disclosed subject matter, a location enabled headset is disclosed. In some examples, a first headset comprises a transceiver for receiving and transmitting sound signals, a processor for processing location and for modifying the sound signal to create an immersive sound, and two or more speakers to transmit the modified sound to the wearer of the first headset. In one example, the first headset is enabled with a location system that receives location input from an item, such as a second headset or person. The location system receives the location input from the second headset and modifies the sound received from that second headset so that the wearer of the first headset perceives the sound received from the second headset location. In a still further example, the first headset is

2273502vl _ 2 - equipped with a microphone for receiving sound input from, by example, the wearer of the first headset to be received by one or more receivers, such as the second headset. The sound input is modified by the processor to simulate a surround sound or three dimensional inputs.

Although a modified sound wave may be most appreciated when a headset or a device having only two speakers (a left and right channel) is used, the presently disclosed subject matter may also be used, and is within the scope of the present invention, with a device having any number of speakers. Further, although the following description is applied to a sound signal for playback having a left and right channel, it is contemplated and should be understood to be within the scope of the presently disclosed subject matter that the same modification may be applied to a sound signal having more than two channels, whether they are played back using a two speaker system or more than two speaker system.

According to an embodiment of the presently disclosed subject matter, the processor is configured to modify the sound signal received at the headset. In some examples, the headset may be configured with a first control that modifies the relative gain of the sound wave between the right and left channels (or additional channels in some configurations) at various frequencies as well as a second control (which may incorporated into the first control or used as a separate control) that modifies the relative gain of the sound wave at various frequencies.

The relative gain adjustment, differential frequency adjustment, is the relative gain difference between two or more channels of audio at a certain frequency or range of frequencies. For example, in a two channel system having a right and left channel, if the gain of the sound wave at 800Hz is adjusted to be 32dB and the gain of the 800Hz component of the sound wave is adjusted to be 20dB, the differential frequency adjustment is 12dB. The differential frequency adjustment may be based on several factors including, but not limited to, the desired perceived location of sound, the type of sound, the particular frequency makeup of the sound, and the amount of phase shifting.

For example, in a sound wave that has a significant portion of its components in the upper frequency bands, the differential frequency adjustment necessary to cause the listening to perceive where the location of the sound is may be small as compared to a sound wave that has very little upper frequency band components. In another example, the differential frequency adjustment may vary depending on the amount of phase shift applied to the sound wave. Additionally, the differential frequency adjustment may be made in various forms. For example, if the desired differential frequency adjustment is 12dB at 800Hz between a left channel and a right channel, the gain of the left channel at 800Hz may be increased 12dB while the right channel may be held constant. In another example, the gain at 800Hz in the left channel may be

2273502vl _ 3 _ increased 6dB while the gain at 800Hz in the right channel may be decreased 6dB, resulting in a differential frequency adjustment of 12dB. It should be noted that differential frequency adjustment is not limited to the gain adjustment according to these examples but also includes other relative adjustments.

To that effect, a sound signal having a left and right channel may be modified in at least two ways to preferably generate surround or three dimensional sounds to the listener. In one process for a particular sound having a left and right channel to at least be partially played back in a left and right speaker, a sound event in the left channel is time shifted, i.e. offset or phase shifted, from the same sound event in the right signal. This may also be termed phase shifting. In another process, the gains for various frequencies of the sound event for the left and right channels are adjusted so that one channel has a different gain the other channel(s). This may be termed differential frequency adjustment. In a still further process, the left and right channels (or other channels if using more than two speakers) are combined for playback. A sound event may include, but is not limited to, a sound that has been recorded from a similar event. For example, an explosion may be a sound event. It should be understood that a portion or the entire sound event may be phase shifted as well as a portion or all of the sound event may be adjusted for frequency gain.

In one example, the device is a headset having on the headset one or more controls that adjust the phase shift at one or more frequencies of the sound wave and one or more controls that adjust the frequency gain of one or more frequencies of the sound wave. The controls may be located in various places on the headset.

In another example, the presently disclosed subject matter comprises a plurality of location enabled headsets in communication with each other. When a sound is transmitted by one of the headsets, relative location information is also transmitted. When the information is received by the other of the plurality of headsets, processors within the other of the plurality of headsets receive the sound signal and the relative location information and modify the sound signal so that the wearer of the particular headset perceives the sound to be heard from the relative location of the transmitting headset to the receiving headset.

In another example, a headset may be configured to transmit a high frequency signal and receive echoes of that signal at the headset. In this example, the headset may be configured to determine the size, shape, location, or other information, from the received echoes, process the echoes, and provide a sound to the wearer of the headset to provide the information received.

The foregoing summarizes some beneficial aspects of the present invention, but is not intended to be reflective of the full scope of the present invention as claimed. Additional

2273502vl _ 4 _ features and advantages of the present invention are set forth in the following description, are apparent from the description, or learned by practicing the present invention. Moreover, the foregoing summary and following detailed description are exemplary and explanatory, and are intended to provide further explanation of the present invention as claimed. BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate multiple exemplary embodiments of the present invention and, together with the description, serve to explain the principles of the present invention. They are not intended in any manner to limit the scope of the present invention. Headings provided herein are for convenience only and do not necessarily affect the scope or meaning of the claimed invention.

FIGURE 1 is a screenshot of a waveform for a sound illustrating the temporal offsetting of a left and right channel.

FIGURE 2 is a screenshot of another waveform for a sound illustrating the temporal offsetting of a left and right channel.

FIGURE 3 is a diagram illustrating temporal offsetting, or as it may be called, phase shifting.

FIGURE 4 is an illustration showing the adjustment of frequency gain of a left channel. FIGURE 5 is an illustration showing the adjustment of frequency gain of a right channel. FIGURE 6 is an illustration of a system and method of modifying a sound wave according to an aspect of the presently disclosed subject matter.

FIGURE 7 is an illustration of a device for modifying a sound wave according to an aspect of the presently disclosed subject matter.

FIGURE 8 is an exemplary flow diagram of sound processing of modifying a sound wave according to an embodiment of the presently disclosed subject matter.

FIGURE 9 is an exemplary illustration showing several location enabled headsets according to an embodiment of the presently disclosed subject matter.

FIGURE 10 is an exemplary illustration showing a location enabled headset used to provide location information of objects around the user according to an embodiment of the presently disclosed subject matter.

2273502vl _ 5 _ DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

The subject matter of the various embodiments of the present invention is described with specificity to meet statutory requirements. However, the description itself is not intended to limit the scope of the claimed invention. Rather, it has been contemplated that the claimed invention can be embodied in other ways, to include different steps or elements similar to the ones described in this document, in conjunction with other present or future technologies. Although the term "step" can be used herein to connote different aspects of methods employed, the term should not be interpreted as implying any particular order among or between various steps herein disclosed unless and except when the order of individual steps is explicitly required. It is also to be understood that the mention of one or more method steps does not preclude the presence of additional method steps or intervening method steps between those steps expressly identified.

It should be noted that, as used in the specification and the claims, the singular forms "a," "an" and "the" include plural references unless the context clearly dictates otherwise. Ranges can be expressed herein as from "about" or "approximately" one particular value and/or to "about" or "approximately" another particular value. When such a range is expressed, other exemplary embodiments include from the one particular value and/or to the other particular value. The terms "comprising" or "containing" or "including" mean that at least the named component, element, apparatus, or method step is present in the system or article or method, but does not exclude the presence of other components, materials, apparatus, or method steps, even if the other such components, material, particles, and method steps have the same function as what is named.

Sound waves are compression waves that interact with the eardrum. Although not completely understood by researchers, it is generally believed that in order to detect the location of various sounds, the brain processes sound waves to determine time difference or amplitude. For example, to determine the location of a sound at generally lower frequencies, the brain, it is thought, measures the time difference between the arrival time of the sound at the two ear drums and processes the sound location according to the time. It is likely this reason that, when trying to locate the direction of a low amplitude sound, a person will typically rotate their head (and thus ears) to increase the amount of information provided to the brain to locate the sound. Recent research indicates that, at higher frequencies, though, it is contemplated that the brain uses the amplitude of the sound in the ears as the location information source.

In the art of today, especially for sound emanating from only two channels (a left and right channel), sound is modified using the time difference method, i.e. phase shifting, in an

2273502vl _ _ attempt to trick the brain into "determining" that a sound is emanating from somewhere other than headphone speakers. If done properly, this may work for lower frequencies, but the inventor has found that it is inadequate for the higher frequencies. Further, the amount of phase shifting that may be applied is limited by the characteristics of the sound wave itself. Thus, it is possible that the sound wave limits the amount of shifting that may be applied before the brain hears two different sounds rather than a single sound. Thus, while increasing the amount of shifting may increase the immersive or three dimensional sound coming from a set of speakers, the current art is limited because of the focus on the phase shift.

The presently disclosed subject matter provides an ability to increase the effect of a phase shift while simultaneously providing for the effect of higher frequency portions of a sound wave. The presently disclosed subject matter uses a combination of phase shifting and adjustment of the gain of various high frequency portions (frequency shift) of a sound wave. Although it is understood that every person is different, the presently disclosed subject matter is performed to attempt to both increase the effect of phase shifting of a sound wave as well as increase the three dimensional aspect of various frequencies of a sound wave. Although the presently disclosed subject matter is not intended to be held to any scientific theory, without holding the scope of the invention to any one particular theory of operation, the adjustment of the gain of the higher frequencies of a sound wave enhances the effect of the phase shifting as well as provides the necessary stimulation for higher frequency sounds.

With regards to enhancing the effect of phase shifting, again, not holding to one specific theory of operation, an increase in the difference of gains of higher frequency portions of a sound wave serve to stimulate the brain so that the effect of the offset is increased. Higher frequency sounds are typically associated with events that cause the brain to increase its level of activity or awareness. For example, a baby's cry, a scream, and the like, are all sounds having significant portions of the sound wave in the higher frequencies. These are traditionally fight or flight, or "caution", sounds that, over time, have caused the brain to have a heightened state of awareness. The brain may be stimulated by increasing the difference of gains at certain frequencies of the higher frequency portions of various channels of sound wave. Therefore, the inventor believes that, because of the stimulation of the brain, the effect of a sound offset is heightened.

Additionally, because it is believed that the brain processes higher frequency location different than lower frequency location, the current art methods and systems of using phase shifting only provide for immersive or three dimensional effects at the lower frequencies and neglect the higher frequencies. Merely increasing the gain of the entire sound wave, without the request phase shifting and the gain adjustment for each channel, would only cause a louder signal

2273502vl _ 7 _ and would not provide any benefit of adjusting the gain. Thus, current art methods of attempting to create a three dimensional sound are inadequate. Additionally, the current art methods are limited as to the compression ratios that may be used. For example, the presently disclosed subject matter may be used for low bit rate compression ratios of 320 kbps down to 64 kbps, which is the typical range of compression ratios for an MP3 file. This technique of phase shifting and frequency gain adjustment, i.e. differential frequency adjustment, according to the presently disclosed subject matter is described more fully below.

It is documented that the brain first learns how to determine the location of objects by sound. For a period of time after birth, the eyesight of most humans is very poor, providing only a close range of clear sight. For most of that time, the brain learns to process location of objects through sound input. Throughout their lifetime, adults with at least nominal hearing ability are constantly processing sound to determine its location. In other words, using sound for location is a natural process that is constantly refined and used.

Figures 1-6 are provided to help illustrate the sound modification process of the presently disclosed subject matter. Figure 1 is an illustration showing the phase shifting of a left channel in relation to a right channel in a two channel system. As discussed above, the presently disclosed subject matter is not limited to a two channel system but may be applied to various other systems having more than two speakers as well. Shown in Figure 1 are two channels of a sound wave, left channel 100 and right channel 102. Although there are various sound events that are not duplicated in the channel, right channel 102 is phase (or time) shifted 0.075 milliseconds so that the sound events that occur in right channel 102 occur 0.075 milliseconds after the same sound events in left channel 100. In some examples of the present invention, the phase shift may be from 0.001 milliseconds to 0.1 milliseconds, more preferable from 0.03 milliseconds to 0.08 milliseconds and more preferably 0.05 milliseconds to 0.8 milliseconds.

Because the amount that an event of a sound wave may be phase shifted depends on the sound characteristics of the sound, the amount of phase shifting may vary from application to application. For example, Figure 2 is illustrative of a sound wave having two channels, left channel 200 and right channel 202, that are phase shifted to a lesser degree than that performed in Figure 1. In Figure 2, right channel 202 is phase shifted 0.047 milliseconds after left 200. As discussed before, this is done in an attempt to alter the perceived location of the sound. Thus, in some instances, the sound emanating from a headset will not be perceived as to be coming from the headset, but rather, from one or more locations surrounding the listener, thus creating the three dimensional effect. Further, as discussed before, the amount of phase shifting that can be applied to two or more channels can be limited to the sound itself. That is, too much phase

2273502vl _ g _ shifting may create a garbled sound, may create an echo effect, or may create other undesirable effects. Figure 3 is a diagram illustrating phase shift. Left channel wave form 300 is shifted ahead of right channel wave form 302 by time difference 0.

Thus, in an attempt to both increase the effect of a phase shift as well as provide for a three dimensional effect of higher frequency portions of a sound, the presently disclosed subject matter also provides for the adjustment of the difference at certain frequencies of the of a sound wave between one or more channels. Although what may be defined as a higher frequency may vary among those of ordinary skill in the art, as applied to the presently disclosed subject matter, the higher frequency may be deemed to be frequencies from various bands of frequencies of the audible hearing range, but are preferable frequencies above 1.5kHz to approximately 18kHz.

Figures 4 and 5 are exemplary left and right channels of a sound wave which, in an exemplary use, would be listened to by a user. The two figures combined illustrate the differential frequency adjustment in a two channel system. It should be understood that the presently disclosed subject matter is not limited to a two channel system and that Figures 4 and 5 are used merely for explanatory purposes. Figure 4 is a graph showing the adjustment of frequencies in an exemplary left channel of a sound wave. It should be understood that the frequencies specified in this or other figures in which the gain is adjusted are exemplary frequencies. It is within the scope of this presently disclosed subject matter that the relative gain, or differential frequency adjustment, may be adjusted for any number of frequencies.

Further, the differential frequency adjustment for each frequency is by way of example and should not be viewed as a limitation. As shown, at 116Hz, a low frequency, a gain of 6.5db is applied. At 215Hz, another low frequency, the gain of minus 1.2db is applied. At a midrange frequency, 877Hz, a gain of 1.6db is applied. At a higher midrange frequency, 2.55kHz, a gain of 2.9db is applied. Further, at a high frequency, in this case 4.91kHz, a gain of 8.8db is applied. Thus, at the higher frequencies, the gain applied is increased an in attempt to provide for the three dimensional feel of the higher frequency portions of a sound wave as well as to stimulate the brain into increasing the effect of the phase shifting at the lower frequencies.

Figure 5 is a graph showing the adjustment of frequencies in an exemplary right channel of a sound wave which, by way of example, may or may not be used in conjunction with the sound wave shown in Figure 4. It should be understood that the frequencies specified in this or other figures in which the gain is adjusted are exemplary frequencies. It is within the scope of this presently disclosed subject matter that the differential frequency adjustment may be adjusted for any number of frequencies. Further, the gain adjusted for each frequency is by way of example and should not be viewed as a limitation. As shown, at 150Hz, a low frequency, a gain

2273502vl _ 9 _ of 5.9db is applied. At 284Hz, another low frequency, a gain of 1.8db is applied. At a midrange frequency, 810.3Hz, a gain of minus 1.8db is applied. At a higher midrange frequency, 2.41kHz, a gain of 1.6db is applied. Further, at a high frequency, in this example, 3.95kHz, a gain of 10.8db is applied. Thus, at the higher frequencies, the differential frequency adjustment applied is increased an in attempt to provide for the three dimensional feel of the higher frequency portions of a sound wave as well as to stimulate the brain into increasing the effect of the phase shifting at the lower frequencies.

It should be noted that, in one embodiment of the presently disclosed subject matter, the differential frequency adjustment is adjusted using different set points and different frequencies. The reason for this, as discussed earlier, is that if differential frequency adjustment gains for the same high frequency in the left and right channels are adjusted to be the same, this may decrease the quality of the sound. With the phase shifting that puts the lower frequencies at a different perceived location, if the higher frequencies are not compensated for, the phase shifting may cause the brain to be "confused" as to the location of the sound, thus creating poor sound effects.

The presently disclosed subject matter may be implemented using various means of phase shifting and differential frequency adjustment. Figure 6 illustrates a system and method for modifying a sound signal. The phase of a sound wave is shifted at step 600. In a two channel system having a left and right channel, the phase shifting is applied between the left and right channels. In a system having more than two channels, the phase shifting may be applied between two or more channels on the same side, two or more channels on the opposite side, or various combinations. Step 600 is not limited to phase shifting between two channels on the opposite sides (i.e. a left and right channel). At step 602, a differential frequency adjustment is applied. Preferably, one or more of the high frequencies of a sound wave have their gains adjusted to a degree necessary or preferred.

It should be noted that steps 600 and 602 may be performed in various orders or in multiple steps. For example, the higher frequencies of a left and right channel may have their gains adjusted prior to phase shifting. Further, and by way of example, if the system includes four channels, one upper left and lower left, and one upper right and lower right, the differential frequency adjustment and phase shifting of the various channels may be adjusted in various orders to create the desired effect. Additionally, steps 600 and 602 may be performed using hardware components or software.

Additional aspects are contemplated and are considered to be within the scope of the present invention. For example, an additional embodiment may include the coordination of the objects in a video having three dimensions along with the sounds of one of more of those objects.

2273502vl - 10 - For example, a three dimensional spatial grid may be devised in which various positions in the grid are associated with various phase shifting and differential frequency adjustment. The video may be overlaid on that grid and objects within the object may be assigned various coordinates based upon their determined position within the grid. The positions are input into a system that applies the particular phase shifting and differential frequency adjustment to attempt to cause the brain to perceive that the object not only is in a certain position visually, but also is in a certain position audibly. The object location may be determined in the grid using various means.

Figure 7 illustrates an exemplary device that may be used in conjunction with the presently disclosed subject matter. Shown is headphone 700 having left earpiece 702 and right earpiece 704. A sound file that comes into headphone 700 typically comprises a left and right channel for each headpiece. In the present configuration, the sound file left and right channels would come into headphone 700 and be adjusted using modification panel 706. Modification panel 706 may comprise various controls, including, but not limited to: volume adjust 708; phase shift adjust 710; and differential frequency adjustment 712. To manually modify the sound wave entering into headphone 700 to be played using speakers (not shown) in left earpiece 702 and right earpiece 704, the user (not shown) adjusts controls 708, 710 and 712.

To adjust the phase shift of the sound wave, the user may increase or decrease the phase between the left and right channels by using phase shift adjust 710. Phase shift adjust 710 may be configured to control the phase shift of the sound wave of the left and right channels at specific frequencies, such as lower frequencies of the sound wave, or may be configured to control the phase shift between the entire left and right channels. Additionally, phase shift adjust 710 may be configured to have preloaded default or recommended settings.

To adjust the differential frequency adjustment of the sound wave, the user may increase or decrease the frequency gain between the left and right channels by using differential frequency adjustment 712. Differential frequency adjustment 712 may be configured to control the gain of the sound wave of the left and right channels at specific frequencies, such as higher frequencies of the sound wave, or may be configured to control the gain between the entire left and right channels. Additionally, differential frequency adjustment 712 may be configured to have preloaded default or recommended settings.

Figure 8 is an exemplary functional block diagram of a process for modifying a sound wave. It should be noted that the order of the constituents of the process is merely for explanatory purposes and should not be interpreted as a limitation of the scope of the application. A sound wave is input 800 and acted upon by either differential frequency adjustment 802 or phase shift 804, or both. For example, the sound wave's phase shift may be adjusted using phase

2273502vl - 11 - shift 804 while the differential frequency adjustment may be held constant by not adjusting differential frequency adjustment 802. The volume of the sound may be adjusted using volume adjust 806, with the output going to device output 808 (which may be a pair of headphone speakers). It should be noted that the inclusion of volume adjust 806 is exemplary only, as the volume may be adjusted at various stages or outside the process of Figure 8.

Figure 9 is an illustration of an exemplary use of one or more location enabled headsets according to an embodiment of the presently disclosed subject matter. Headset 900 is configured to receive location information and sound from one or more sources, process the location and modify the sound according to the location, and play the modified sound in the headset speakers. Shown within a transmission range of headset 900 are headsets 904-908. Headset 900 has microphone 902 for inputting sound to the transmitted to one or more locations. Headsets 904- 908 may be similarly equipped with microphones, although the presently disclosed subject matter is not limited to each headset requiring a microphone.

When headset 900 receives a sound signal from headset 908, the sound signal is accompanied by, either in the same transmission or in another transmission, information regarding the relative location of headset 908 to headset 900. Shown in Figure 9 are exemplary cardinal points "N", "S", "W" and "E" showing the directions of north, south, west and east, respectively. In Figure 9, headset 908 is to the southwest of headset 900. Therefore, in this present example, along with a sound that may be received at headset 900 from headset 908 will be information that signifies that headset 908 is to the southwest of headset 900. Headset 900 will receive the sound information and modify the sound according to the location information and play that sound through headset 900 speakers (not shown).

Preferably, the sound played through the speakers of headset 900 will make the wearer of headset 900 perceive that the sound coming from headset 908 is to the southwest of headset 900. In that manner, the wearer of headset 900 may be able to determine the location of headset 908 from the modified sound even if the wearer of headset 900 is not in a location or in an environment to see or keep track of the wearer of headset 908. The presently disclosed subject matter is not limited to sound location between any particular headsets. In the same manner described above, a sound transmitted from headset 906 received at headset 904 contains location information of headset 906 relative to headset 904.

The sound received at any one of headsets 900, 904, 906, or 908 may be speech created by the wearer of a particular headset (i.e. the wearer speaks into the microphone) or may be a tracking sound. In another example, the tracking sound may occur at regular intervals or may be initiated upon a user request. For example, a team may want to keep track of the whereabouts of

2273502vl - 12 - each other without having to speak. In this example, one or more of the headsets may keep track of the location of itself in relation to the other headsets. In another example, information may be received at each headset that provides for the ability of that headset to determine the location of the other headsets.

Referring back to Figure 9, a beacon may be transmitted by one or more of the headsets in Figure 9 to be received by the one or more headsets. The beacon may be a tone or other sound that identifies the actual wearer of the headset or may be a tone that identifies "friend" as in a friend or foe interrogation situation. Headset 900 may receive the beacon for headset 906 and, along with location information of headset 906 in relation to headset location 900, play a sound in headset 900 that provides location information of headset 906. The beacon may be received at one headset, such as headset 900, or may be received at more than one headset. This may be used in various instances. For example, in a combat situation, it may be useful to maintain knowledge of the location of teammates or fellow soldiers.

In another example, headset 900, or another device, may be configured to receive sound input from the environment in which headset 900 is being used. This sound input may be movement in a room in a building, such as may be the case in close quarters combat. Because the user of headphone 900 has been able to keep track of the location of headsets 904, 906 and 908, the user may be able to react quicker to the unexpected sound. For example, the unexpected sound may be an enemy approaching from another room. Even though the user may not immediately fire upon the enemy (not knowing if the enemy is friend or foe), by being alerted to an unexpected sound or movement, the user may be able to posture themselves for protection quicker than in a situation in which the user may be unsure as to the location of his or her squad.

Although not limited to any particular physical configuration, one or more of headphones 900, 904, 906 and 908 may be integrated with a combat helmet. Additionally, speakers in one or more of headphones 900, 904, 906 and 908 may be configured to have one speaker for each ear or multiple speakers for each ear. Additionally, one or more of headphones 900, 904, 906 and 908 may be configured to be noise cancelling or noise abating. For example, in close combat situations, the sound coming from weapon discharges may be significant enough to cancel out any other noises from the combat area. Therefore, by way of example, headphone 900 may be configured to receive sound from around the wearer of headset 900 and, if the sound is at certain intensity levels, either block the sound or reduce the sound intensity. This may provide the user with the sound input necessary to determine dangers or provide input for decisions but reduce the intensity to allow the other inputs to be used.

2273502vl - 13 - The use of sound information may be used in a manner similar to the way animals in nature use sound to locate objects or maneuver within their environment. For example, bats use echolocation techniques to fly in near-dark conditions. Figure 10 illustrates an exemplary embodiment of echolocation using various embodiments of the presently disclosed subject matter. Headset 950 is configured to receive sound input and location information to modify the sound for playback on the speakers of headset 950. The modified sound, when listened to by the user, is preferably modified so that the user "hears" the sound from the location of the source of the sound. Headset 950 is also configured to have a sound transceiver (not shown) capable of transmitting and receiving sound information.

For example, the transceiver of headset 950 may transmit sound wave 952, which is preferable an inaudible, high frequency sound wave, but may be a sound wave of various frequencies. Sound wave 952 propagates through the air until it "hits" and "bounces off of an object. As shown in Figure 10, exemplary objects are tree 954 and human 958. When sound wave 952 hits and bounces off of tree 954, an echo may be formed, illustrated as sound wave 956. Preferably, sound wave 956 is received at the transceiver of headset 950 and processed. For example, the location of tree 954 in relation to headset 950 may be determined at headset 950 by the time and angle of reception at headset 950. For example, the transceiver of headset 950 may use an omni-directional microphone that is capable of picking up sounds from multiple angles.

In one example, the headset 950 processes the location of tree 954 and causes a sound to be played on the speakers of headset 950 that provide location information of tree 954. In some examples, sound wave 956 may be further analyzed to provide additional information, such as the type of object. In this example, a tree or other foliage, such as tree 954, because of its structure may cause an echo (or multiple echoes) with characteristics that identify it as foliage. The reason for this is that when sound hits tree 954 (or bush or other similar object), the sound bounces off branches, leaves, the trunk, and other parts of tree 954 to create an echo dissimilar to a sound hitting and bouncing off a more solid object, such as human 958. Because human 958 has a more singular or compact structure, sound wave 960 may have different characteristics than sound wave 956. Headset 950 may use this information to provide the user with additional input such as the type of object. This may be especially useful to a person having little to no eyesight but wishes to function in a moving environment, such as a city. A blind person may use headset 950 to identify curbs, moving cars, humans, light poles, etc., to provide the blind person with the ability to move within that environment.

2273502vl - 14 - While it is envisioned that numerous embodiments of the present invention are particularly well-suited for computerized systems, nothing in this document is intended to limit the invention to such embodiments. On the contrary, as used herein the term "computer system" is intended to encompass any and all devices capable of storing and processing information and/or capable of using the stored information to control the behavior or execution of the device itself, regardless of whether such devices are electronic, mechanical, logical, or virtual in nature.

The various techniques described herein can be implemented in connection with hardware or software or, where appropriate, with a combination of both. Thus, the methods and apparatuses of the present invention, or certain aspects or portions thereof, can take the form of program code (i.e., instructions) embodied in tangible media, such as floppy diskettes, CD- ROMs, hard drives, or any other machine-readable storage medium, wherein, when the program code is loaded into and executed by a machine, such as a computer, the machine becomes an apparatus for implementing various embodiments of the present invention.

The program(s) can be implemented in assembly or machine language, if desired. In any case, the language can be a compiled or interpreted language, and combined with hardware implementations. The methods and apparatuses for implementing various embodiments of the present invention can also be practiced via communications embodied in the form of program code that is transmitted over some transmission medium, such as over electrical wiring or cabling, through fiber optics, or via any other form of transmission, wherein, when the program code is received and loaded into and executed by a machine, such as an EPROM, a gate array, a programmable logic device (PLD), a client computer, or the like. When implemented on a general-purpose processor, the program code combines with the processor to provide a unique apparatus that operates to invoke the functionality of various embodiments of the present invention. Additionally, any storage techniques used in connection with the present invention can invariably be a combination of hardware and software.

While the present disclosure has been described in connection with a plurality of exemplary embodiments, as illustrated in the various figures and discussed above, it is understood that other similar embodiments can be used or modifications and additions can be made to the described embodiments for performing similar functions of the present invention without deviating therefrom. Therefore, the present invention should not be limited to any single embodiment, but rather construed in breadth and scope in accordance with the following claims.

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Claims

What is Claimed:

1. A computer readable storage medium having instructions stored thereon for modifying a sound signal comprising a left and right channel, the instructions comprising instructions to: receive the sound signal;

receive location information of the sound signal; and

modify the sound signal based on the location information to create a modified sound signal.

2. The computer readable storage medium of claim 1, wherein the location information of the sound signal comprises location relative to at least one point of reference.

3. The computer readable storage medium of claim 2, wherein the at least one point of reference is a reference point in a video.

4. The computer readable storage medium of claim 1, wherein the instructions to modify the sound signal based on the location information to create a modified sound signal further comprise instructions to apply a phase shift between the left channel and the right channel.

5. The computer readable storage medium of claim 4, wherein the phase shift is 0.001 milliseconds to 0.1 milliseconds, 0.03 milliseconds to 0.08 milliseconds, or 0.05 milliseconds to 0.8 milliseconds.

6. The computer readable storage medium of claim 1, wherein the instructions to modify the sound signal based on the location information to create a modified sound signal further comprise instructions to apply a differential frequency adjustment.

7. The computer readable storage medium of claim 6, wherein the instructions to apply a differential frequency adjustment is applied to frequencies from 100Hz to 18kHz.

8. The computer readable storage medium of claim 6, wherein the instructions to apply the differential frequency adjustment comprises instructions to increase the gain of a plurality of higher frequency components of the sound signal a greater magnitude than a plurality of lower frequency components of the sound signal.

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9. The computer readable storage medium of claim 5, wherein the differential frequency adjustment is applied differently to the left channel as compared to the right channel.

10. A method for modifying a sound signal comprising a left and right channel, the method comprising:

receiving the sound signal;

receiving location information of the sound signal; and

modifying the sound signal based on the location information to create a modified sound signal.

11. The method claim 10, wherein the location information of the sound signal comprises location relative to at least one point of reference.

12. The method of claim 11, wherein the at least one point of reference is a reference point in a video.

13. The method of claim 10, wherein modifying the sound signal based on the location information to create a modified sound signal further comprises applying a phase shift between the left channel and the right channel.

14. The method of claim 13, wherein the phase shift is 0.001 milliseconds to 0.1

milliseconds, 0.03 milliseconds to 0.08 milliseconds, or 0.05 milliseconds to 0.8 milliseconds.

15. The method of claim 10, wherein modifying the sound signal based on the location information to create a modified sound signal further comprises applying a differential frequency adjustment.

16. The method of claim 15, wherein applying a differential frequency adjustment is applied to frequencies from 100Hz to 18kHz.

17. The method of claim 15, wherein applying the differential frequency adjustment comprises increasing the gain of a plurality of higher frequency components of the sound signal a greater magnitude than a plurality of lower frequency components of the sound signal.

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18. The method of claim 15, wherein the differential frequency adjustment is applied differently to the left channel as compared to the right channel.

19. A sound signal that is modified to create a modified sound signal, the modified sound signal stored on a computer readable storage medium, the sound signal modified by:

receiving the sound signal;

receiving location information of the sound signal; and

modifying the sound signal based on the location information to create a modified sound signal, wherein modifying the sound signal comprises:

applying a phase shift between the left channel and the right channel; and applying a differential frequency adjustment.

20. The sound signal of claim 19, wherein the location information of the sound signal comprises location relative to at least one point of reference.

21. The sound signal of claim 20, wherein the at least one point of reference is a reference point in a video.

22. The sound signal of claim 19, wherein the phase shift is 0.001 milliseconds to 0.1 milliseconds, 0.03 milliseconds to 0.08 milliseconds, or 0.05 milliseconds to 0.8 milliseconds.

23. The sound signal of claim 19, wherein applying a differential frequency adjustment is applied to frequencies from 100Hz to 18kHz.

24. The sound signal of claim 19, wherein applying the differential frequency adjustment comprises increasing the gain of a plurality of higher frequency components of the sound signal a greater magnitude than a plurality of lower frequency components of the sound signal.

25. The sound signal of claim 15, wherein the differential frequency adjustment is applied differently to the left channel as compared to the right channel.

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