Abstract:
A simplified method of controlling the operating mode of a wireless communications device, particularly the speaker mode, includes operating a wireless communications device according to a selected default mode. The method of audio output, such as through a loud speaker or through a quieter speaker, is determined, at least in part by the default mode setting. The device includes at least a first key and a second key. Pressing the first key causes the device to automatically initiate a call session in radio mode and stay in radio mode until the end of the call session. On the other hand, pressing the second key causes the device to automatically initiate a call session in phone mode and stay in phone mode until the end of the call session. In either case, the wireless communications device reverts to the default mode when the call session ends. By doing so, the user is provided with a simple method for temporarily switching to the desired mode of operation, without the necessity of first determining the current mode of the wireless communications device and through the simple press of a single key. This method is particularly adapted for use with wireless communications devices having two separate speakers, a quiet one for phone mode and a louder one for radio mode.

Description:
FIELD OF THE INVENTION 
     The present invention relates to the field of portable wireless communications devices, and more particularly to a method of operating mode selection in portable wireless communications devices. 
     BACKGROUND OF THE INVENTION 
     The use of portable wireless communications devices, such as cellular phones, personal communications assistants, and the like, is rapidly increasing throughout society. As their use has spread, so have demands for increased functionality, with resultant increase in the complexity of such devices. 
     Using a cellular phone as an example, these devices attempt to mimic traditional landline telephones, but typically with additional functionality, such as portability. One very desirable aspect of most cellular phones is the ability to engage in full duplex communications. In the typical one-on-one conversation, full duplex operation allows both parties to simultaneously speak, as contrasted with the old prior art of mobile trunked-radio phones which allow only one party to speak at a time. In addition, with conference call or other multi-party capability, more than two parties can talk simultaneously. For ease of reference, this full duplex mode of operation will be referred to as “phone mode” The details of phone mode operation in cellular phones are well known in the art. 
     Some cellular phones are not only capable of operating in phone mode, but also in what will be referred to herein as radio mode. Examples of such devices may be seen in U.S. Pat. No. 5,450,618, which is incorporated herein by reference, and U.K. Patent Application GB2269721. In radio mode, the phone appears to the user to handle communications in a half-duplex manner. That is, the cellular phone does not appear to the user as simultaneously transmitting and receiving voice data. Instead, the user must push a button known as a push-to-talk (PTT) button in order to include data corresponding to the user&#39;s voice in the data transmitted; otherwise, the phone appears to the user as if it is receiving only. The systems and general operations associated with phones using radio mode also well known in the art. 
     Cellular phones designed to operate in both phone mode and radio mode typically include two distinct speakers for audio output. In phone mode, the audio output, based on the communications signals exchanged with a remote location, are output via a low volume speaker, typically located on the phone body at the opposite end from the phone&#39;s microphone. Thus, in phone mode, the low volume speaker is typically proximate the user&#39;s ear while the microphone is proximate the user&#39;s mouth. This low volume speaker typically has a variable volume audio output that may be controlled by dials or other known means. However, the output of the low volume speaker is typically limited to a maximum allowed volume that will not damage a typical user&#39;s hearing even at the highest setting. For radio mode, the phone uses a different high volume speaker, typically located proximate the microphone end of the phone. This high volume speaker also typically has variable volume; however, the maximum allowed audio volume for this speaker it typically much higher than that of the low volume speaker. The higher allowed audio volume is required for the phone&#39;s output to be heard when the phone is not proximate the user&#39;s head, such as for receiving a page while the phone is clipped to a user&#39;s belt. The phone in U.S. Pat. No. 5,450,618 has this arrangement. 
     One problem with phones that can operate in both phone mode and radio mode is switching between modes. Typically, if a user wants to place a call in radio mode, the user must first determine the current mode of the phone. Assuming that the phone is in phone mode, the user must press a mode selection button to toggle the mode, press the PTT button to originate the call, and then at call release, press the mode selection button to return the phone back to phone mode. This is a cumbersome procedure that many users fail to fully complete, thereby leading to less than satisfactory performance. A similar procedure must be used to place a call in phone mode when the phone is in radio mode. 
     Thus, there remains a need for a simplified method of selecting the mode of the phone, and particularly the speaker to be used. Such a method should cause the wireless communications device to automatically return to its default operating mode when the call is complete while also requiring a minimum of key press operations to switch modes. 
     SUMMARY OF THE INVENTION 
     The present invention provides a simplified method of controlling the operating mode of a wireless communications device, particularly the speaker mode. The wireless communications device operates according to a selected default mode and handles incoming messages according to that mode. In particular, the method of audio output, such as through a loud speaker or through a quieter speaker, is determined, at least in part, by the default mode setting. 
     One preferred embodiment of the wireless communications device includes at least a first key and a second key. When initiating an outgoing call, pressing the first key causes the wireless communications device to initiate a call session in radio mode and stay in radio mode until the end of the call session, unless changed by a user. On the other hand, pressing the second key causes the wireless communications device to initiate a call session in phone mode and stay in phone mode until the end of the call session, unless changed by a user. In either case, the wireless communications device reverts to the default mode when the call session ends. The present invention provides the user with a simple method for temporarily hot-switching to the desired mode of operation, without the necessity of first determining the current mode of the wireless communications device. Thus, rather than having to navigate a complex menu system or press multiple keys, the user may temporarily change operating modes of the wireless communications device through the simple press of a single key. While this method is operative with wireless communications devices having a single multiple-mode speaker, the method is particularly adapted for use with wireless communications devices having two separate speakers, a quiet one for phone mode and a louder one for radio mode. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is perspective view of one embodiment of a wireless communications device according to the present invention. 
     FIG. 2 is a schematic representing the wireless communications device of FIG.  1 . 
     FIG. 3 is a simplified flow chart showing the process flow of one temporary mode selection method of the present invention. 
    
    
     DETAILED DESCRIPTION 
     One preferred embodiment of a wireless communications device  20  of the present invention is shown in FIGS. 1 and 2. For clarity of illustration, a cellular telephone capable of transmitting and receiving digital signals will be used as an example of a wireless communications device  20  in the following discussion, but the invention is not so limited. Indeed, the present invention may apply to any wireless communications device  20 , including cellular telephones, personal communications assistants, and so forth, whether using analog or digital communications. 
     The cellular telephone  20  typically includes a controller  22 , an operator interface  26 , a transmitter  38 , a receiver  50 , and an antenna assembly  58 . The operator interface  26  typically includes a display  28 , keypad  30 , control unit  32 , microphone  34 , and two speakers  80 , 85 . The display  28  allows the operator to see dialed digits, call status, and other service information. The keypad  30  allows the operator to dial numbers, enter commands, and select options. The control unit  32  interfaces the display  28  and keypad  30  with the controller  22 . The microphone  34  receives acoustic signals from the user and converts the acoustic signals to an analog electrical signal. Speakers  80 , 85  convert analog electrical signals from the receiver  50  to acoustic signals which can be heard by the user. As necessary, there may be a switch (not shown) disposed in the circuit path leading to the speakers  80 , 85  for limiting the audio output to one speaker or the other. Such a switch should operate under the control of the controller  22 , either directly or indirectly. 
     The analog electrical signal from the microphone  34  is supplied to the transmitter  38 . The transmitter  38  includes an analog to digital converter  40 , a digital signal processor  42 , and a phase modulator and RF amplifier  48 . The analog to digital converter  40  changes the analog electrical signal from the microphone  34  into a digital signal. The digital signal is passed to the digital signal processor (DSP)  42 , which contains a speech coder  44  and channel coder  46 . The speech coder  44  compresses the digital signal and the channel coder  46  inserts error detection, error correction and signaling information. The DSP  42  may include, or may work in conjunction with, a DTMF tone generator (not shown). The compressed and encoded signal from the digital signal processor  42  is passed to the phase modulator and RF amplifier  48 , which are shown as a combined unit in FIG.  2 . The modulator converts the signal to a form, which is suitable for transmission on an RF carrier. The RF amplifier then boosts the output of the modulator for transmission via the antenna assembly  58 . 
     The receiver  50  includes a receiver/amplifier  52 , digital signal processor  54 , and a digital to analog converter  56 . Signals received by the antenna assembly  58  are passed to the receiver/amplifier  52 , which shifts the frequency spectrum, and boosts the low-level RF signal to a level appropriate for input to the digital signal processor  54 . 
     The digital signal processor  54  typically includes an equalizer to compensate for phase and amplitude distortions in the channel corrupted signal, a demodulator for extracting bit sequences from the received signal, and a detector for determining transmitted bits based on the extracted sequences. A channel decoder detects and corrects channel errors in the received signal. The channel decoder also includes logic for separating control and signaling data from speech data. Control and signaling data is passed to the controller  22 . Speech data is processed by a speech decoder and passed to the digital to analog converter  56 . The digital signal processor  54 , may include, or may work in conjunction with, a DTMF tone detector (not shown). 
     The digital to analog converter  56  converts the speech data into an analog signal which is applied to one of the speakers  80 , 85  to generate acoustic signals which can be heard by the user, as described in more detail below. 
     The antenna assembly  58  is connected to the RF amplifier of the transmitter  38  and to the receiver/amplifier  52  of the receiver  50 . The antenna assembly  58  typically includes a duplexer  60  and an antenna  62 . The duplexer  60  permits full duplex communications over the antenna  62 . 
     The controller  22  coordinates the operation of the transmitter  38  and the receiver  50 , and may for instance take the form of a common microprocessor. This coordination includes power control, channel selection, timing, as well as a host of other functions. The controller  22  inserts signaling messages into the transmitted signals and extracts signaling messages from the received signals. The controller  22  responds to any base station commands contained in the signaling messages, and implements those commands. When the user enters commands via the keypad  30 , the commands are transferred to the controller  22  for action. Memory  24  stores and supplies information at the direction of the controller  22  and preferably includes both volatile and non-volatile portions. 
     The keypad  30  includes a plurality of keys, including at least a first key  70  and a second key  75 . For purposes of this illustration, the first key  70  is a send key and the second key is a PTT key. It is to be understood that the keys of the keypad  30  may be physical keys or virtual keys (such as shown on the display  28 ), and the keys do not need to be disposed on only one area of the phone  20 . Indeed, it is preferred that the send key  70  be located some distance from the PTT key  75 . For instance, the send key  70  may be proximate a common three by four telephone key array disposed on a front face of the phone  20  while the PTT key  75  may be located on the side of the phone  20 , proximate the display  28 . See FIG.  1 . 
     The phone  20  also includes two speakers  80 , 85 . The first speaker  80  is low volume speaker, typically located above the display  28  so as to be proximate the user&#39;s ear when the phone  20  is held next to the user&#39;s head in the traditional telephone handset orientation. The second speaker  85  is a high volume speaker typically located on the opposite end of the phone  20  from the low volume speaker  80 . See FIG.  1 . The low volume speaker  80  acts as the phone&#39;s primary speaker when the phone is in “phone mode,” and the high volume speaker  85  acts as the phone&#39;s primary speaker in “radio mode,” as discussed in more detail below. 
     After selection of the appropriate destination phone number, pressing (and then releasing) the send key  70  or the PTT key  75  begins a call session. A call session is a communications session between the phone  20  and a remote location, typically another phone  20 . The call session begins with a call origination and ends with a call release. Pressing the send key  70  starts a call session in phone mode. Phone mode is simply a phone operational mode that is characterized by full duplex operation of the phone  20  in any manner well known in the art, such as according to ANSI-136. In phone mode, a conversation appears to the user of the phone  20  to be simultaneously bi-directional. This behavior is common in digital cellular phones of the prior art. The call session may be between the phone  20  and a single destination, or may optionally be between the phone  20  and a plurality of destinations, such as a conference call. 
     In contrast, pressing the PTT key  75  starts a call session in radio mode. Radio mode is a phone  20  operational mode wherein the phone  20  appears to the user to be operating in a half duplex mode. In radio mode, a conversation appears to the user of the phone  20  to be bi-directional, but not simultaneously. Instead, during the call session, the operation of the microphone  34  and the&#39;speaker  85  are mutually exclusive. When the PTT key  75  is pushed, the microphone  34  of the phone  20  is active; when the PTT key  75  is not pushed, the speaker  85  is active. This type of operation is familiar to users of old fashioned trunked-radio phones. Thus, when in radio mode, the phone  20  mimics the man-machine interface of a trunked-radio phone. As in phone mode, the call session in radio mode may be between the phone  20  and a single destination, or may optionally be between the phone  20  and a plurality of destinations, such as a conference call. 
     Preferably, this radio mode behavior of the phone  20  is localized to the phone  20 , meaning that the communications between the phone  20  and the remainder of the wireless communications system are as a digital cellular phone in phone mode, but the man-machine interface appears to the user to be like a trunked-radio phone. Thus, when the phone  20  is operating in radio mode, the phone  20  may appear to the remainder of the communications system as being either full duplex or half duplex. The only requirement on the phone operating in radio mode is that the phone  20  appear to the user as being half duplex, regardless of the reality as viewed from the perspective of the communications system. The radio mode operation of a phone  20  is further disclosed in co-owned U.S. patent application Ser. No. 09/234,191 which is incorporated herein by reference. 
     Importantly, when the phone  20  is in phone mode, the primary audio output from the phone  20  should be via the low volume speaker  80  and when the phone is in radio mode, the primary audio output of the phone  20  should be via the high volume speaker  85 . 
     When the phone  20  is powered on, and at other appropriate subsequent times, the user may select the operating mode (e.g., phone or radio) via any method known in the art, such as via a selection menu displayed on the display  28 . Alternatively, the phone may choose the operating mode without intervention of the user. For purposes herein, this selected operating mode is known as the default mode. The controller should keep track of the current default mode, such as by storing an indicator thereof in memory  24 . 
     Typically, the user will operate the phone  20  in the default mode, participating one or more call sessions. However, as often arises, the user may wish to place a call in a particular mode. For instance, the user may wish to place a conference call to a number of locations and may wish the phone  20  to begin radio mode so as to minimize interference with the other participants. The present invention allows the user to do so without necessarily knowing the present operating mode of the phone  20 . For this example, the user selects the appropriate conference call number via any known method (box  110 ), and then presses the PTT key  75  (box  120 ). Pressing the PTT key  75  (box  120 ) causes the controller  22  to assume radio mode as its operational mode. If the controller  22  is already in radio mode (box  130 ), then this assuming of radio mode means simply staying in radio mode. If instead, the controller  22  is not in radio mode (box  130 ), the controller  22  changes to radio mode (box  140 ). The controller  22  then initiates a call in radio mode (box  150 ). The controller stays in radio mode during the balance of the call session (box  160 ). Consistent with the discussion above, this means that the high volume speaker  85  is used as the primary audio output during the call and the user must press the PTT key  75  to activate the microphone  34 . At the end of the call session (box  160 ) the controller  22  reverts to the default mode (box  190 ). This means, for instance, that the controller  22  changes to the phone mode if phone mode is the selected default mode, or the controller  22  stays in radio mode if radio mode is the selected default mode. Typically, the phone  20  will then enter a standby state, as is well known in the art. Thus, by simply pressing the PTT key  75  to originate a call (box  120 ), the user may be sure that the phone  20  will operate according to radio mode for that particular call but will revert to the selected default mode when the call ends (box  190 ). 
     Similarly, the user may place a phone mode call regardless of the current default mode by pressing the send key  70  (box  220 ). The user selects the appropriate destination number via any known method (box  110 ), and then presses the send key  70  (box  220 ). Pressing the send key  70  (box  220 ) causes the controller  22  to assume phone mode as its operational mode. If the controller  22  is already in phone mode (box  230 ), then this assuming of phone mode means simply staying in phone mode. If instead, the controller  22  is not in phone mode (box  230 ), the controller  22  changes to phone mode (box  240 ). The controller  22  then initiates a call in phone mode (box  250 ). The controller stays in phone mode during the balance of the call session (box  260 ). Consistent with the discussion above, this means that the low volume speaker  80  is used as the primary audio output during the call and the user need not press any key to activate the microphone  34 . At the end of the call session (box  260 ) the controller  22  reverts to the default mode (box  190 ). This means, for instance, that the controller  22  changes to the radio mode if radio mode is the selected default mode, or the controller  22  stays in phone mode if phone mode is the selected default mode. Typically, the phone  20  will then enter a standby state, as is well known in the art. Thus, by simply pressing the send key  70  to originate a call (box  220 ), the user may be sure that the phone  22  will operate according to phone mode for that particular call but will revert to the selected default mode when the call ends (box  190 ). 
     Optionally, the display  28  may be used to display the current default mode and/or the current override mode if present. Thus, in case of problems, the user may easily determine which of the speakers  80 , 85  should be operating. 
     The discussion above has assumed that the phone includes at least two speakers  80 , 85 . However, this is not required. In some embodiments, the phone includes only one speaker, for instance the speaker  80  located far from the microphone  34 . As above, the speaker  80  operates under the control of the controller  22 . However, the speaker  80  in such a situation would have at least two operating speaker modes, corresponding to phone mode and radio mode. In phone mode, the speaker  80  would have a maximum allowed audio volume that is relatively low (e.g. 18 dB), while in radio mode, the speaker  80  would have a maximum allowed audio volume that is relatively higher (e.g. 90 dB). Thus, while the actual speaker volume may vary depending on user controlled volume settings and the incoming signal, the speaker mode, and thus the maximum volume of the speaker  80 , can be controlled depending on the operating mode of the phone  20 . 
     It should be noted that the selection of the number to be called may be made in any fashion known in the art. For instance, the user may first input the number directly via the keypad  30  or by selecting a number stored in memory through a menu on the display  28 . Alternatively, there may be a default number assigned to each key on the keypad, optionally including the send key  70  and the PTT key  75 , to facilitate speed dialing. 
     Using the present invention, the user is supplied with a simple method of temporarily hot-switching to the desired mode of operation. If the user decides to place a radio mode call, the user may initiate the radio mode call by pressing the PTT key  75  without having to worry about the current mode of the phone  20 . Conversely, if the user decides to place a phone mode call, the user may initiate the phone mode call by pressing the send key  70  without having to worry about the current mode of the phone  20 . In either case, the phone  20  will revert to the default mode at the conclusion of the call. Thus, rather than having to navigate a complex menu system or press multiple keys, the user may temporarily change operating modes of the phone  20  and initiate a call through the simple press of a single key. 
     The present invention may, of course, be carried out in other specific ways than those herein set forth without departing from the spirit and essential characteristics of the invention. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein.