GB2382241A

GB2382241A - Controlling the volume of a speaker in response to the proximity to an object

Info

Publication number: GB2382241A
Application number: GB0126742A
Authority: GB
Inventors: Mark Corbridge
Original assignee: Sendo International Ltd
Current assignee: Sendo International Ltd
Priority date: 2001-11-07
Filing date: 2001-11-07
Publication date: 2003-05-21
Anticipated expiration: 2021-11-07
Also published as: GB0126742D0; GB2382241B

Abstract

The volume of a speaker may be controlled in dependence on its proximity to an object. For example, in the case of a mobile phone, the phone may be operated in speaker phone mode if it is detected as being close to some object, such as a desk, otherwise operating in private mode. In an alternative embodiment the proximity to the user may be detected. Various means of proximity detection are disclosed including capacitative, optical and mechanical.

Description

SPEAKER CONTROL MEANS AND METHOD OF OPERATION Field of the Invention This invention relates to an apparatus and method of adjusting a audio enunciator volume level. The invention is applicable to, but not limited to, an apparatus and method for configuring two or more modes of a speaker for an audio communication device such as a wireless phone.

Background of the Invention In the field of this invention it is known for mobile communication devices, for example mobile or cellular phones, to comprise a speaker, as well as a microphone, RF circuitry and antenna, a display, user interaction means such as a keypad and any other components necessary for the communication device to operate as intended.

In particular, wireless communication devices often include a speakerphone option, which allows a user to communicate by voice with minimal physical operation requirements. A speakerphone is a telephone or telephone attachment equipped with both loudspeaker and microphone, thus permitting one or several persons to participate in a call at the same time without the telephone receiver being held.

Hence, such wireless communication devices include a first, private mode of operation, where the device's speaker is used during a call. In this mode of operation, the speaker outputs audio signals to a user at a relatively low amplitude level. In this first, private mode of operation, the communication device is generally held by a user such that the speaker is located substantially adjacent an ear of the user. The low audio amplitude level of the audio signal is therefore set such that the user is capable of hearing the audio signals emitted by the speaker, whilst ensuring that the user suffers no discomfort or damage to their hearing.

In a second, speakerphone mode of operation of the communication device, hereinafter referred to as an 'open'mode of operation, the speaker is used during a call, to provide audio signals to a user, or plurality or users, at a higher amplitude level. In this second, open mode of operation, the communication device is preferably located at a distance from the user, for example, on a top surface of a table or desk. The second, higher amplitude of the audio signals must therefore be loud enough for the user (s) to be capable of hearing the audio signals emitted by the speaker, even though the speaker may be located some distance from the ear (s) of the user (s).

A problem that can arise from a communication device having two such modes of operation is that the user of the device may make use of the communication device, believing the communication device to be in the first,

private mode of operation, when in fact it is in the second, open mode of operation. The audio signals emitted from the speaker when the communication device is in the second, open mode of operation are intended to be heard by a user when the speaker is some distance from the ear of the user. As such, the audio amplitude of these signals is substantially higher than that of the audio signals emitted by the speaker when the communication device is in the first, private mode of operation.

Consequently, if the user is holding the communication device/speaker substantially adjacent the ear of the user with the communication device in the second, open mode of operation, the amplitude of the audio signals will cause discomfort to the user, and could even cause damage to the hearing of the user.

It is therefore desirable for such a communication device to include means for reducing the likelihood of the communication device being in an open mode of operation when held substantially adjacent an ear of a user during, for example, a call or playing back a recorded audio message.

A known solution, that satisfies this need, is provided by a phone cradle or holder, in which the communication device can be placed. The communication device includes means for detecting when it is in the cradle or holder, and only then enables an open mode of operation. Thus, since it is unlikely that a user would position his/her

ear close to the phone cradle or holder to participate in a call, the high audio level initiated in this'open' mode of operation will not damage a user's hearing.

A significant problem with this method is that it is not possible for the communication device to operate in an open mode without the cradle or holder, for example by positioning the device in the middle of a table for a group conference call.

A second solution to reduce the likelihood of the communication device being in an open mode of operation, when held substantially adjacent an ear of a user, is to determine an orientation of a flip cover with respect to the communication device. This technique is used in devices such as cellular phones, where the flip covers of such devices are capable of being located in different positions.

In a first position, the cellular phone is disabled from operating in the open mode of operation, and only capable of operating in the private mode of operation. In a second position of the flip cover, the cellular phone is enabled for working in the open mode of operation. In general, the second position of the flip cover is such that the flip cover extends substantially perpendicular from the body of the phone, providing an obstruction when the user attempts to hold the phone substantially adjacent the ear of the user.

Therefore, the user will move, almost automatically, the flip cover into the first position when wishing to hold the cellular phone substantially adjacent an ear, thus ensuring that the cellular phone is operating in a private mode. The problem with the method is that it requires the communication device to comprise a flip cover. Furthermore, this technique is too reliant upon the means for accurately determining the orientation of the flip cover with respect to the device. In addition, the technique is also too reliant on the user using the cellular phone in the expected manner and orientation.

Thus, there exists a need in the field of the present invention to provide an improved means and method for a communication unit to differentiate between modes of operation that affect the volume of a speaker's output, wherein the abovementioned disadvantages may be alleviated.

Statement of Invention In accordance with a first aspect of the present invention, there is provided an audio communication device, as claimed in Claim 1.

In accordance with a second aspect of the present invention, there is provided a method of enunciating an audio signal of an audio communication device, as claimed in Claim 12.

In accordance with a third aspect of the present invention, there is provided a storage medium storing processor-implementable instructions, as claimed in Claim 14.

Further aspects of the present invention are as Claimed in the dependent claims.

In summary, the present invention proposes, inter-alia, to provide a detection means for detecting when a lower surface of a communication device is proximal, or substantially adjacent, to an object. When the detection means detects an object is proximal, or substantially adjacent, to the lower surface of the communication device, the communication device is capable of operating in a higher audio amplitude mode of operation. The higher audio amplitude mode of operation, similar to a speakerphone mode of operation, enables a user to hear audio signals from the device when it is located at a distance from the ear of the user.

Brief Description of the Drawings Exemplary embodiments of the present invention will now be described, with reference to the accompanying drawings, in which:

FIG. 1 illustrates a portable audio communication device capable of being adapted in accordance with the preferred embodiment of the present invention; FIG. 2 illustrates a portable audio communication device in situ capable of being adapted, in accordance with the preferred embodiment of the present invention; FIG. 3 illustrates a capacitive proximity switch acting as a detection means in a communication device, in accordance with one embodiment of the present invention; FIG. 4 illustrates an optical switch arrangement acting as a detection means in a communication device, in accordance with an alternative embodiment of the present invention ; FIG. 5 illustrates a mechanical switch acting as a detection means in a communication device, in accordance with a further alternative embodiment of the present invention; and FIG. 6 illustrates a flowchart for setting a speaker audio level output of a communication device, in accordance with the preferred embodiment of the present invention.

Description of Preferred Embodiments

FIG. 1 illustrates an audio communication device, which in the illustrated embodiment is in the form of a cellular phone 100. It is within the contemplation of the invention that the audio communication device may be alternatively a portable or mobile radio, a digital or analogue wireless telephone, a computer or wirelessly networked PC with an audio output, or indeed any speaker- based communication device.

The cellular phone 100 comprises a front face 112, a rear face (not shown) opposing the front face 112, an upper surface 114, a lower surface 120, a first side surface 116 and a second side surface 118. The cellular phone 100 further comprises a display 122, keypad 124, microphone 126 and an audio enunciator such as a speaker 128, each located on the front face 112. An antenna 130 is typically located on the upper surface 114.

The speaker 128 may be connected to an audio output level adjustment means 134, to control the audio level emitted from the speaker 128. Alternatively, the audio level may be controlled by the receiver's processor 136, in setting an appropriate audio output level of the demodulated, decoded received voice signal.

During a call, when a user of the cellular phone 100 holds the cellular phone 100 with the speaker 128 substantially adjacent an ear of the user, a hand of the user generally comes into contact with the first and second side surfaces 116,118 and the rear face of the cellular phone 100. Thus, when the cellular phone 100 is

used in this way, the lower surface 120 is generally not in contact with any part of the user, or any other object.

In accordance with the preferred embodiment of the invention, detection means 132 are provided to detect when the lower surface 120 of the cellular phone 100 is proximal to an object. The detection means, in whatever form they take, is preferably coupled to a processing function 136. When the detection means 132 detects that an object is proximal to the lower surface 120, the cellular phone 100 is arranged to be capable of operating in an open mode of operation. In this open mode of operation, the speaker 128 of the cellular phone 100 is configured to emit higher amplitude audio signals.

To effect this higher audio output level mode of operation, the processor 136 preferably receives a signal from the detection means 132, indicating that an object (other than a user's hand) is near. The processor 136 then adjusts the audio level output by appropriate setting of the audio adjustment level means. The audio adjustment level means may take any number of forms, as known to those skilled in the art, such as a variable attenuator, a variable level audio output signal from the processor 136, etc.

Such a speakerphone configuration is advantageous to a user during, for example, a call when the cellular phone 100 is located at a distance from the ear of the user.

In this mode of operation, the cellular phone 100 may be

located on, for example, a table or desk near to the user, and still enable the user to hear the audio sigals enunciated from the speaker 128.

However, when the detection means 132 fails to detect an object as being positioned proximal to the lower surface 120 of the cellular phone 100, the cellular phone 100 is disabled from operating in the open mode of operation.

In this lower audio amplitude mode of operation, the cellular phone 100 operates in a private mode of operation. However, in this mode, the audio level is arranged to be sufficient for the audio signals to be of a level that they can typically be heard by the user when the speaker 128 is positioned substantially adjacent the ear of the user.

Thus, if the user of the cellular phone 100 wishes to use the open mode of operation, for example so that other persons in the vicinity of the cellular phone 100 may listen or participate in a call, the user can place the cellular phone 100 on a surface, for example on a table or desk 232, such that the cellular phone 100 rests on its lower surface 120, as illustrated in FIG. 2. The detection means 132 detects the proximity of the table or desk 232 on which the cellular phone 100 has been placed, and preferably initiates the open mode of operation via the processor 136.

As previously explained, if the cellular phone 100 were capable of operating in the open mode when the speaker 128 of the cellular phone 100 is located substantially

adjacent an ear of the user, then the high amplitude of audio signal emitted from the speaker 128 could cause discomfort and possibly damage to the ear and hearing of the user. The present invention substantially overcomes this in the provision of the detection means 132, coupled with the mode of operation being determined in response to the detection means 132.

Preferably, the mode of operation of the cellular phone 100 is configured in a real-time manner by the detection means 132. When the cellular phone 100 is removed from the table or desk 232, the detection means 132 no longer detects an object, such as the table or desk 232, proximal to the lower surface 120 of the cellular phone 100. Hence, the cellular phone disables the open mode of operation.

In a first embodiment of the invention, the ability to enter an open mode of operation is user-selectable.

Preferably, the user is able to select the open mode of operation from, for example, a menu option of the cellular phone 100. Alternatively, a single press of a button of the keypad 124 may select the open mode of operation. Alternatively, the'open'mode of operation may be incorporated into the audio communication device as an automatic, standard feature.

Once the open mode of operation has been configured as an optional mode in the communication device, it is envisaged that this mode can be entered automatically.

Hence, for example, if a user commences a call in a

private mode of operation and, during the call, wishes the phone to enter an open mode of operation, the user only needs to place the lower surface 120 of the cellular phone 100 on an object. Once, the proximity of the object has been detected by the detection means 120, the open mode of operation is automatically enabled.

If a user does not select the open mode of operation option, or subsequently de-selects the open mode of operation after having selected the option, the detection of an object by the detection means 132 is ignored. In this manner, the cellular phone is only configured to operate in the private mode, irrespective of its proximity to any object such as a desk 232.

It is envisioned that the detection means 132 may comprise any one, or combination, of a number of types of switching/sensing devices. A first preferred switching/sensing configuration, using a capacitive proximity switch, is shown in FIG. 3.

The capacitive proximity switch illustrated in FIG. 3 comprises a signal generator 334 that provides a signal to an input of a microprocessor 136. The signal generator is also connected to a capacitive plate 338, which is preferably located substantially adjacent the lower surface 120 of the cellular phone 100. The frequency of the signal generated by the signal generator 334 is dependent upon the capacitance of the capacitive plate 338.

Thus, when an object approaches the capacitive plate 338, the object acts as a second capacitive plate effectively connected to ground. Thus, the capacitive plate 338 together with the object forms a capacitor where the capacitance varies relative to the distance between the capacitive plate 338 and the object.

When the object is proximal to the lower surface 120 of the cellular phone 100, and therefore in the proximity of the capacitive plate 338, the capacitance provided by the capacitive plate 338 is relatively large in comparison to when the object is distal from the cellular phone 100.

As the capacitance provided by the capacitive plate 338 increases, the frequency of the signal provided by the signal generator 334 also increases. This increase in frequency of the signal is detected by the microprocessor 136. When the frequency of the signal exceeds a threshold, the microprocessor determines that an object is sufficiently near to, or at least substantially adjacent, the lower surface 120 of the cellular phone 100. If the user has selected an open mode of operation for such a determination, the cellular phone 100 switches into an open mode of operation.

In a further alternative embodiment of the present invention, the detection means 132 includes an optical switch comprising, for example, an infrared light source and sensor, as illustrated in FIG. 4. The infrared light

source and sensor in this example are in the form of a light emitting diode 444 and photodiode 442, although other light emitters and light detectors can be used.

The photodiode is coupled to the base of a transistor 440, the output of which is coupled to a microprocessor 136. The LED 444 and photodiode 442 are located proximal to the lower surface 120 of the cellular phone 100. In use, when on object is positioned proximal to the lower surface 120 of the cellular phone 100, the infrared light emitted from the LED 444 is reflected off the object and detected by the photodiode 442.

When the intensity of the infrared light detected by the photodiode 442 increases, the resistance of the photodiode 442 decreases. Thus, when the intensity of infrared light detected by the photodiode 442 is low (i. e. when there is no object near the lower surface 120 of the cellular phone 100), the voltage at the base of the transistor 440 is high. In this case, the signal received by the microprocessor 136 is also high.

However, when the intensity of infrared light detected by the photodiode 442 is high (i. e. when an object is proximal to the lower surface of the cellular phone 100) the voltage at the base of the transistor 440 is low.

Hence, the signal received by the microprocessor is low, or grounded. Thus, when the microprocessor detects a sufficiently low signal that the base voltage falls below a threshold level, the processor determines that there is an object proximal to the lower surface 120 of the cellular phone 100. If open mode of operation has been

selected by the user, or the mode is configured as a standard feature on the phone, the open mode of operation is enabled.

It is within the contemplation of the invention that any similar threshold-based arrangement may be user-definable or may be configurable by a manufacturer or operator. It is also within the contemplation of the invention that a processor 136 of a cellular phone 100 (or other audio communication device) may be re-programmed with an algorithm, or specific threshold level, supporting the inventive concepts of the present invention, as described above. More generally, according to the preferred embodiment of the present invention, such re-programming to dynamically vary an enunciated audio level may be implemented in a respective cellular phone 100 (or other audio communication device) in any suitable manner. For example, a new memory chip may be added to a conventional cellular phone 100 (or other audio communication device).

Alternatively, existing parts of a conventional cellular phone 100 (or other audio communication device) may be adapted, for example by reprogramming one or more processors therein. As such, the required adaptation may be implemented in the form of processor-implementable instructions stored on a storage medium, such as a floppy disk, hard disk, programmable read only memory (PROM), random access memory (RAM) or any combination of these or other storage multimedia.

A further alternative embodiment of the present invention is shown in FIG. 5, where the detection means 132 comprises a mechanical switch. In this embodiment, an input of the microprocessor 136 is connected to a power supply V+, via a mechanical switch 546.

When there is no object located proximal to the lower surface 120 of the cellular phone 100, the mechanical switch 546 is'open'. This causes the input of the microprocessor 136 to be grounded via a resistor 548.

Hence, the microprocessor receives a low signal.

When an object contacts the lower surface 120 of the cellular phone 100, the mechanical switch 546 is 'closed'. In another embodiment, opening of the mechanical switch 546 can clearly be effected when an object contacts the lower surface 120 of the cellular phone 100. This, in turn, causes the voltage at the input of the microprocessor 136 to become equal to the V+ supply. Such an increase in voltage is detected by the microprocessor 136, which subsequently enables, if selected by the user, the open mode of operation.

It is within the contemplation of the invention that other detection circuits or configurations, in addition to the preferred examples for implementing the detection means 132 as described with reference to FIG. 3, FIG. 4 and FIG. 5, could benefit from the inventive concepts hereinbefore described.

In summary, the inventive concept (s) of the present invention is/are further illustrated in the flowchart 600 of FIG. 6. First, the communication device needs to be configured to offer an'open'mode of operation by any of the aforementioned techniques, as shown in step 610. The detection means determine when the communication device is positioned proximal to an object, as in step 620. If a change in the position of the communication device is detected, the processor switches the communication device into an open mode of operation, as shown in step 630, 640.

This mode of operation is maintained until it is determined that the device is no longer situated proximal to an object, as in step 630. When it is determined that the device is no longer situated proximal to an object, the mode of operation is switched to a private mode of operation, as in step 650.

In this manner, the audio speaker mode of operation of the communication device is dependent upon the proximity of an object to the communication device.

Of course, the various components within the cellular phone 100 can be realised in discrete or integrated component form. Furthermore, it is within the contemplation of the invention that any audio enunciating communication device, with any form of adjustment means to adjust the level of an audio enunciated signal could benefit from the inventive concepts described herein.

Typical examples of adjustment means would include processor controlled audio output signals where the appropriate audio levels are output from the processor to the speaker. Alternatively, a processor or controller could control the amplification of an audio amplifier, or attenuation of an audio signal attenuator, connected to the speaker.

It will be understood that the means and method for a communication unit to differentiate between modes of operation that affect the volume of a speaker's output, as described above, provides at least the following advantages : (i) The detection means does not rely on a cradle or holder ; (ii) The configuring of an open mode of communication is not reliant on the expected manner of device use by the device user; (iii) The communication device is not required to include a flip cover; and (iv) The communication device can more easily automatically switch between an open mode and a private mode of communication.

Whilst the specific and preferred implementations of the embodiments of the present invention are described above, it is clear that one skilled in the art could readily apply variations and modifications of such inventive concepts.

Thus, an improved means and method for a communication unit to provide different modes of operation that affect the volume of a speaker's output have been described wherein the aforementioned disadvantages associated with prior art arrangements have been substantially alleviated.

Claims

Claims 1. An audio communication device comprising : an audio enunciator for enunciating a received audio signal; an audio enunciator level adjustment function operably coupled to the audio enunciator for adjusting an enunciated level of the received audio signal; and detection means, operably coupled to the audio enunciator level adjustment function, detecting a spatial position of the audio communication device, wherein the enunciated level of the received audio signal is adjusted in response to said detected spatial position.
2. The audio communication device according to Claim 1, further comprising a processor, operably coupled to said audio enunciator level adjustment function and said detection means to interpret an output signal of said detection means and in response to said output adjust the audio level of the enunciated received audio signal.
3. The audio communication device according to Claim 1 or Claim 2, wherein the audio enunciator of the audio communication device is configured to operate at a higher audio level in a speakerphone mode when the detection means determines that the audio communication device is distal from the audio communication device's user.
4. The audio communication device according to Claim 1 or Claim 2 or Claim 3, wherein the audio enunciator of the audio communication device is configured to operate

<Desc/Clms Page number 21>

at a lower audio level in a private mode when the detection means determines that the audio communication device is proximal to the audio communication device's user.
5. The audio communication device according to any preceding Claim, wherein the detection means is located at or near to a lower surface of the audio communication device such that the detection means determines that the lower surface of the audio communication device is proximal to an object to configure the communication device to operate at a higher audio level.
6. The audio communication device according to any preceding Claim, wherein the detection means comprises a capacitive proximity switch.
7. The audio communication device according to Claim 6, wherein the capacitive proximity switch includes a capacitive plate operably coupled to a signal generator, such that the detection means detects a spatial position of the audio communication device by detecting a frequency or change in frequency of a signal output from the signal generator based on a change in capacitance of the capacitive plate caused by a proximity of the object.
8. The audio communication device according to any of preceding Claims 1 to 5, wherein the detection means comprises an optical detection arrangement.

<Desc/Clms Page number 22>
9. The audio communication device according to Claim 8, wherein the optical detection arrangement includes light emitting means and light detecting means, such that the detection means detects a spatial position of the audio communication device by said light detecting means detecting a reflected signal transmitted from said light emitting means.
10. The audio communication device according to any of preceding Claims 1 to 5, wherein the detection means comprises a mechanical switching arrangement that is open or closed when the audio communication device contacts an object, thereby configuring the communication device to operate at a higher audio level.
11. The audio communication device according to any preceding Claim, wherein the audio communication device is one of the following: a cellular phone, a portable or mobile radio, a digital or analogue wireless telephone, a computer having an audio enunciator.
12. A method of enunciating an audio signal of an audio communication device, the method comprising the steps of: configuring the audio communication device to offer at least a higher audio level and a lower audio level mode of operation; detecting when the audio communication device is proximal to an object ; and operating the audio communication device in a higher audio level mode of operation when the audio

<Desc/Clms Page number 23>

communication device is detected as being proximal to the object.
13. The method of enunciating an audio signal of an audio communication device according to Claim 12, the method further comprising the step of : operating the audio communication device in a lower audio level mode of operation when the audio communication device is detected as being distal from the object.
14. A storage medium storing processor-implementable instructions for controlling one or more processors to carry out the method of Claim 12 or Claim 13.
15. An audio communication device substantially as hereinbefore described with reference to, and/or as illustrated by, any of FIGs 1 to 5 of the accompanying drawings.
16. A method of enunciating an audio signal substantially as hereinbefore described with reference to, and/or as illustrated by, FIG. 6 of the accompanying drawings.