Radio communication apparatus for a selected one of a plurality of terminal units of different kinds

Abstract: In a radio communication apparatus which is capable of using a selected terminal unit selected from a plurality of terminal units, a logic part (31) detects a kind of the selected terminal unit to produce a kind signal representative of the selected kind. Responsive to the kind signal, the logic part controls an adjusting part (24) which produces an adjusted signal. As a result, the adjusted signal has a selected level which is selected for the selected terminal unit in accordance with the kind signal. Responsive to the adjusted signal, the selected terminal unit generates an audible signal having a volume which is adjusted in accordance with the selected level. It is a matter of course that the volume can be manually adjusted by an operator.

Description: This invention relates to a radio communication apparatus, such as a telephone set, for use in combination with a terminal unit. A recent technical development known to the applicants but not published has brought about a telephone set which has various user interface functions. In one of the user interface functions, the telephone set is used in combination with a selected terminal unit which is selected from a plurality of terminal units of different kinds and is of a selected kind. The telephone set includes a receiving part for receiving a radio signal to produce a received signal and an adjusting part for adjusting the received signal to produce an adjusted signal. The selected terminal unit is provided with an ear piece receiver or an announcing unit for announcing an announce by generating an audible signal having an adjustable volume which can be adjusted in accordance with the adjusted signal. Various handsets of different kinds are developed as the terminal units for the telephone set. A handset of a first one of the kinds comprises a control unit for producing an announce control signal which can be adjusted in response to operation of a volume key. Responsive to the announce control signal, the telephone set controls the audible signal. It is necessary for the first kind that the adjusted signal has a first selected level. Another handset of a second one of the kinds is provided with an adjustable volume member for adjusting the volume of the audible signal independently of the telephone set and is of low price. It is necessary for the second kind that the adjusted signal has a second selected level which is different from the first selected level. In addition, it is possible to use, as the selected terminal unit, a particular handset which comprises a loudspeaker. When the particular handset is used as the selected terminal unit, it is unnecessary on carrying out communication for an operator to hold the particular handset by hands. In this event, it is necessary that the adjusted signal has a third selected level which is different from each of the first and the second selected levels. Accordingly, it is desired that the adjusted signal is automatically adjusted to have a level which is suitable for the selected terminal unit. In the specification of United States patent No. 4,718,080, which was published on January 5 1988, there was proposed a microprocessor controlled interface for a cellular radio telephone system which enabled a user to communicate with the system using conventional telephony devices. The microprocessor decoded known manufacturer's protocols to render the interface compatible with various types of equipment. Features of radio communication apparatus to be described below are that it is capable of using a terminal unit selected from a plurality of terminal units of different kinds, and that it employs a signal which is automatically adjusted to have a level which is suitable for a selected terminal unit. One radio communication apparatus to be described below is for use in combination with a selected terminal unit which is selected from a plurality of terminal units of different kinds and is thus of a selected kind, the radio communication apparatus including receiving means for receiving a radio signal to produce a received signal and adjusting means for adjusting the received signal to produce an adjusted signal. A particular radio communication apparatus to be described below to illustrate one example employing the invention includes detecting means for detecting the selected kind to produce a signal representative of the selected kind and control means connected to the adjusting and the detecting means for controlling the adjusting means to make the adjusted signal have a selected level which is selected for the selected terminal unit in accordance with the representative signal. The following description and drawings disclose, by means of an example, the invention which is characterised in the appended claims, whose terms determine the scope of the protection conferred hereby. In the drawings:- Fig. 1 shows, together with a handset of a first kind, a radio communication apparatus according to a first embodiment of this invention; Fig. 2 is a schematic diagram of a handset of a second kind; Fig. 3 shows, together with a particular handset, the radio communication apparatus illustrated in Fig. 1; and Fig. 4 is a flow chart for use in describing operation of the radio communication apparatus illustrated in Fig. 3. Description of the Preferred Embodiment: Referring to Fig. 1, a radio communication apparatus according to an embodiment of this invention is carried as a mobile telephone set on an automobile or the like and is for use in combination with a first handset 10 which is selected as a selected terminal unit from a plurality of handsets of different kinds and which is of a first kind. The description will be made at first as regards the first handset 10. The first handset 10 comprises an ear piece receiver or a handset announcing unit 11, a handset microphone 12, a handset volume key 13, a handset control circuit 14, and a handset connector 15. The control circuit 14 is labelled CONT in the figure. The announcing unit 11 is for announcing a handset announce by generating an audible signal having an adjustable volume in response to an adjusted signal which will later become clear. The microphone 12 is for producing an audible frequency signal as a main talk signal and is referred to as a main producing arrangement. The main talk signal is representative of a talk of an operator or user of the radio communication apparatus. The volume key 13 is operated by the operator for producing a handset key signal which is representative of the fact that the volume key 13 is operated by the operator. Supplied with the key signal, the control circuit 14 produces a handset announce control signal which is for determining the volume of the audible signal. The handset connector 15 is for mechanically and electrically connecting the first handset 10 to the radio communication apparatus. Description will be directed to the radio communication apparatus. The radio communication apparatus comprises first and second units 21 and 22. The first unit 21 is a portable telephone set and comprises a radio part 23, an adjusting part 24, an apparatus announcing unit 25, and an apparatus microphone 26. The adjusting part 24 is labelled VOL in the figure. The radio part 23 is a receiving arrangement for receiving a radio signal and has a radio signal terminal E connected through an antenna selection switch 27 to an antenna 28 which will be called a subsidiary antenna hereunder. Supplied with the radio signal, the radio part 23 produces a received signal. The adjusting part 24 is connected to a received signal terminal Rx of the receiving part 23 for adjusting the received signal into an adjusted signal. The announcing unit 25 is connected to the adjusting part 24. Responsive to the adjusted signal, the announcing unit 25 announces an apparatus announce by generating an audible signal having an adjustable volume like the handset announcing unit 11. The apparatus microphone 26 is for producing an audible frequency signal as a subsidiary talk signal and is referred to as a subsidiary producing arrangement. The subsidiary talk signal is representative of the talk of the operator like the handset microphone 12. The talk signal is sent to a talk signal terminal Tx of the radio part 23 through a microphone selection switch 29. Responsive to the talk signal, the radio part 23 transmits a transmission signal to the subsidiary antenna 28 through the antenna selection switch 27. The first unit 21 further comprises a logic part 31, an apparatus volume key 32, and an apparatus power source 33. The volume key 32 consists of an upper and a lower part. The logic part 31 is labelled LOGIC in the figure. The apparatus power source 33 is labelled BATT in the figure. The logic part 31 is connected to each of the radio and the adjusting parts 23 and 24 and is for carrying out operation which will later be described in detail. The volume key 32 is connected to the logic part 31 and is operated by the operator for producing an apparatus key signal like the handset key switch 13. The key signal is sent to the logic part 31. The upper part of the apparatus volume key 32 is for raising the adjustable volume. The lower part is for lowering the adjustable volume. It may be mentioned here that the handset volume key 14 is of similar structure. The power source 33 is for supplying apparatus electric power through a power selection switch 34 to a first unit power line which is connected to various portions of the first unit 21 in the manner known in the art. The first and the second units 21 and 22 are provided with first and second connectors 36 and 37, respectively, and are removably connected to each other by fitting the first and the second connectors 36 and 37 together. For detecting connection between the first and the second units 21 and 22, the radio communication apparatus comprises a permanent magnetic member 38 and an apparatus reed switch 39 which are placed in the second and the first units 22 and 21, respectively. The permanent magnetic member 38 is labelled MAG in the figure and is for generating a magnetic field and is referred to as a generating arrangement. The reed switch 39 is for producing a logical signal when it is placed in the magnetic field with the first unit 21 connected to the second unit 22. Herein, the reed switch 39 is referred to as a local producing arrangement. The logical signal is sent to the logic part 31. Description will be directed to the second unit 22. The second unit 22 is provided with an additional connector 41 which is removably connected to the handset connector 15 of the first handset 10. The second unit 22 comprises an adjusted signal line 42, a talk signal line 43, and an announce control signal line 44. The adjusted signal line 42 connects the handset announcing unit 11 of the first handset 10 to the adjusting part 24 through the first, the second, the additional, and the handset connectors 36, 37, 41, and 15. The talk signal line 43 connects the handset microphone 12 of the first handset 10 to the microphone selection switch 29 through the first, the second, the additional, and the handset connectors 36, 37, 41, and 15. As a result, the talk signal terminal Tx of the radio part 23 is connected to a selected one of the 5 handset and the apparatus microphones 12 and 26 when the microphone selection switch 29 is controlled by the logic part 31 as will later become clear. The announce control signal line 44 connects the control unit 14 of the first handset 10 to the logic part 31 through the first, the second, the additional, and the handset connectors 36, 37, 41, and 15. The announce control signal is sent from the control circuit 14 to the logic part 31 through the announce control signal line 44. The second unit 22 further comprises an electric power line 45 and an antenna line 46. The electric power line 45 connects a main power source 47 of main electric power to each of the antenna selection and the power selection switches 27 and 34 through the first and the second connectors 36 and 37. The main power source 47 is labelled CAR BATT in the figure. The main power source 47 is fixedly mounted on the automobile and is removably connected to the electric power line 45. The antenna line 46 connects a main antenna 48 to the antenna selection switch 27 through the first and the second connectors 36 and 37. The main antenna 48 is fixedly mounted on the automobile and is removably connected to the antenna line 46. In a case where the first unit 21 is connected to the second unit 22 and the second unit 22, to the main power source 47, the main electric power is supplied from the main power source 47 to each of the antenna selection and the power selection switches 27 and 34. In this event, the antenna selection and the power selection switches 27 and 34 have conditions depicted in the figure. As a result, the main power source 47 is connected to the first unit power line of the first unit 21 through the power selection switch 34 to supply the main electric power to the first unit power line. Simultaneously, the main antenna 48 is connected to the radio part 23 through the antenna selection switch 27. Therefore, the radio communication apparatus is capable of carrying out communication by the use of the main power source 47 and the main antenna 48. When the first unit 21 is removed from the second unit 22, the main electric power is not supplied to each of the antenna selection and the power selection switches 27 and 34. In this event, the antenna selection and the power selection switches 27 and 34 have different conditions wherein the subsidiary antenna 28 and the apparatus power source 33 are connected to the first unit power line through the antenna selection and the power selection switches 27 and 34, respectively. Although description is made above in connection with a case where the first handset 10 is selected as the selected terminal unit, it is possible to select, in place of the first handset 10, a second handset 50 illustrated in Fig. 2. The second handset 50 comprises, in addition to an ear piece receiver or a handset announcing unit 51 and a handset microphone 52, an adjustable volume member 53 connected to the announcing unit 51. The adjustable volume member 53 is operable by the operator for adjusting volume of an audible signal generated by the announcing unit 51. The adjustable volume member 53 is, for example, a variable resistor. In a case where the second handset 50 is connected to the second unit 22, it is possible to adjust the volume of the audible signal independently of the radio communication apparatus. Although the figure does not show, it is a matter of course that each of the first and the second handsets 10 and 50 further comprises a hook switch which is well known in the art. In addition, the second unit 22 comprises a particular switch (not shown) which is inserted in the talk signal line 43 to close only when the hook switch is closed. Referring to Fig. 3, description will proceed to a case where third and particular handsets 60 and 70 are connected to the radio communication apparatus. The communication apparatus comprises similar parts designated by like reference numerals. Each of the third and the particular handsets 60 and 70 can be used for the operator as the selected terminal unit. The third handset 60 is removably connected to the second unit 22 through the handset and the additional connectors 15 and 41 like the first handset 10 illustrated in Fig. 1. Herein, the handset connector 15 is connected to the third handset 60 through a flexible handset code (not shown). The particular handset 60 is directly connected to the second unit 22. The second unit 22 comprises a handset selection switch 71 connected to the talk signal line 43. The handset selection switch 71 has first and second contact points a and b and connects the talk signal line 43 to a selected one of the third and the particular handsets 60 and 70. Operation of the handset selection switch 71 is controlled in accordance with a handset selection signal which is sent from the third handset 60. The third handset 60 is similar to the first handset 10 and comprises similar parts designated by like reference numerals. The third handset 60 further comprises a cradle 72 and a hook switch. The handset microphone 12 is connected to the first contact point a of the handset selection switch 71. In this example, the hook switch comprises a handset permanent magnet 73 for generating a cradle magnetic field and a handset reed switch 74 placed in the handset magnetic field. The handset permanent magnet 73 is held to the cradle 72. The handset permanent magnet 73 is labelled H.MAG in the figure. The third handset 60 is usually in contact with the cradle 72. The handset reed switch 74 is therefore placed in the cradle magnetic field. In this event, the handset selection switch 71 has a condition depicted in the figure. When the third handset 60 is removed from the cradle 72, the handset reed switch 74 is placed outside the cradle magnetic field. As a result, the handset reed switch 74 produces an off-hook signal. Supplied with the off-hook signal, the control circuit 14 produces the above-mentioned handset selection signal. In accordance with the handset selection signal, the handset selection switch 71 connects the talk signal line 43 to the handset microphone 12. As will be understood from the above description, the handset microphone 12 produces the main talk signal in response to talk of the operator. When the handset selection switch 71 connects the talk signal line 43 to the handset microphone 12, the main talk signal is sent to the talk signal line 43 through the first contact point a of the handset selection switch 71. The particular handset 70 is generally called a hands-free telephone set and comprises an ear piece receiver or a particular announcing unit 75 which is a loudspeaker well known in the art. Therefore, it is unnecessary on carrying out communication for the operator to hold the particular handset 70 by hands. The particular handset 70 further comprises a particular microphone 76, a transmitting amplifier 77, a controllable transmission attenuator 78, a particular control circuit 79, a particular volume part 81, a controllable reception attenuator 82, a particular adjusting circuit 83, and a receiving amplifier 84. In the figure, the controllable transmission attenuator 78, the particular control circuit 79, the particular volume part 81, the controllable reception attenuator 82, and the particular adjusting circuit 83 are labelled CTA, CONT, PAR VOL, CRA, and VOL, respectively. The second contact point b of the handset selection switch 71 is connected to the transmission attenuator 78. The adjusted signal line 42 is connected to each of the particular control circuit 79 and the controllable reception attenuator 82 irrespective of operation of the handset selection switch 71. Therefore, the adjusted signal is always supplied to each of the particular control circuit 79 and the controllable reception attenuator 82. When the particular handset 70 is used as the selected terminal unit, the handset selection switch 71 connects the talk signal line 43 to the particular handset 70 in accordance with the handset selection signal. The microphone 76 is for producing an audible frequency signal as an original signal which is representative of the talk of the operator. The transmitting amplifier 77 is for amplifying the original signal into an amplified signal. With reference to a particular control signal which will later be described, the controllable transmission attenuator 78 controllably attenuates the amplified signal to produce a particular talk signal which is similar to the main talk signal. When the handset selection switch 71 connects the talk signal line 43 to the particular handset 70, the particular talk signal is sent to the talk signal line 43 through the second contact point b of the handset selection switch 71. The particular volume part 81 is operated by the operator for producing a particular announce control signal in response to operation of the operator. The announce control signal is supplied to each of the particular control and the particular adjusting circuits 79 and 83. Responsive to the announce control, the particular talk, and the adjusted signals, the particular control circuit 79 produces the particular control signal to control operation of each of the controllable transmission and the controllable reception attenuators 78 and 82. The controllable reception attenuator 82 is responsive to the particular control signal for controllably attenuating the adjusted signal into an attenuated signal. The adjusting circuit 83 is responsive to the announce control signal for adjusting the attenuated signal into a particular adjusted signal. The reception amplifier 84 is for amplifying the adjusted signal into an amplified signal. Responsive to the amplified signal, the announcing unit 76 generates a particular audible signal. The description will be directed to operation of the particular control circuit 79. In order to prevent the particular handset 70 from howling by acoustical and sidetone couplings, the particular control circuit 79 carries out comparison between the particular talk and the adjusted signals. When the particular talk signal is strong, the particular control circuit 79 makes the controllable transmission attenuator 78 much attenuate the amplified signal. This mode of operation of the particular control circuit 79 and the controllable transmission attenuator 78 will be called a reception mode. When the particular talk signal is weak, the particular control circuit 79 makes the controllable reception attenuator 82 much attenuate the adjusted signal. This mode of operation of the particular control circuit 79 and the controllable reception attenuator 82 will be called a transmission mode. It will be assumed that the particular volume part 81 is operated to increase the volume of the particular audible signal. When the particular audible signal is too strong, the particular microphone 76 may pick up a part of the particular audible signal. As a result, the part of the particular audible signal is superposed on the original signal. In this event, the particular control circuit 79 makes the controllable transmission attenuator 78 much attenuate the amplified signal. Referring to Fig. 4 together with Fig. 3, the description will proceed to operation of the radio communication apparatus. At a first stage S1, the logic part 31 carries out judgement whether or not the logical signal is produced in the apparatus reed switch 39. When the logical signal is not produced in the reed switch 39, the first stage S1 is followed by a second stage S2 at which the logic part 31 makes the microphone selection switch 29 connect the radio part 23 to the apparatus microphone 26. In this condition, the adjusting part 24 can be controlled by the logic part 31 in accordance with the apparatus key signal to adjust the received signal into the adjusted signal. Responsive to the adjusted signal, the apparatus announcing unit 25 generates the audible signal. Therefore, it is possible to carry out communication by the use of the apparatus announcing unit 25 and the apparatus microphone 26. When the logical signal is produced in the apparatus reed switch 39, the first stage S1 proceeds to a third stage S3 at which the logic part 31 processes the logical signal into a connection detection signal. In this manner, the logic part 31 serves as a processing arrangement. Responsive to the connection detection signal, the logic part 31 makes the microphone selection switch 29 connect the radio part 23 to the talk signal line 43. Herein, the logic part 31 may be referred to as a selecting arrangement. The third stage S3 is followed by a fourth stage S4 at which the handset control circuit 14 carries out judgement whether or not the off-hook signal is produced in the third handset 60. When the off-hook signal is not produced, the fourth stage S4 proceeds to a fifth stage S5 at which the handset control circuit 14 makes the handset selection switch 71 connects the talk signal line 43 to the particular handset 70. The fifth stage S5 is followed by a sixth stage S6 at which the logic part 31 controls the adjusting part 24 to make the adjusted signal have a selected level which is constant. In this event, the volume of the particular audible signal can be adjusted by the particular volume part 81. When the off-hook signal is produced in the third handset 60, the fourth stage S4 is followed by a seventh stage S7 at which the handset control circuit 14 makes the handset selection switch 71 connect the talk signal line 43 to the third handset 60. The logic part 31 produces a request signal in response to the connection detection signal. The request signal is supplied to the handset control circuit 14. Responsive to the request signal, the handset control circuit 14 produces an acknowledge signal which is sent to the logic part 31. It is to be noted in this connection that the acknowledge signal is not sent to the logic part 31 when the second handset 50 is connected to the radio communication apparatus. This is because the second handset 50 does not comprise the handset control circuit 14. The seventh stage S7 proceeds to an eighth stage S8. The logic part 31 carries out judgement whether or not the third handset 60 is connected to the radio communication apparatus with reference to the acknowledge signal. When the third handset 60 is connected, the logic part 31 detects the acknowledge signal. Otherwise, the logic part 31 does not detect the acknowledge signal. Responsive to the acknowledge signal, the logic part 31 produces a kind signal which is representative of the selected kind. In this event, the logic part 31 is referred to as a detecting arrangement. When the third handset 60 is connected to the radio communication apparatus, the eighth stage S8 proceeds to a ninth stage S9 at which the logic part 31 controls the adjusting part 24 to make the adjusted signal have a selected level which is selected for the third handset 60 in accordance with the kind signal. In this event, it is possible to adjust the selected level by the volume key 13. Namely, the logic part 31 controls the adjusting part 24 to make the selected level be further adjusted in response to the handset announce control signal. The logic part 31 is referred to herein as a control arrangement. When the third handset 60 is not connected to the radio communication apparatus, the eighth stage S8 is followed by a tenth stage S10 at which the logic part 31 controls the adjusting part 24 to make the selected level of the adjusted signal be constant. In a case where the selected level of the adjusted signal is constant, it is preferable to use the second handset 50 as the selected terminal unit. In this event, the volume of the audible signal can be adjusted by the adjustable volume member 53. Herein, the logic part 31 is referred to as an internal control arrangement. While this invention has thus far been described in connection with only the preferred embodiment thereof, it will readily be possible for those skilled in the art to put this invention into practice in various other manners. For example, the radio communication apparatus may stationarily be installed although the description is made as regards the automobile or the like. It is a matter of course that another terminal unit may be used as the selected terminal unit.

Claims: A radio communication apparatus for use in combination with a selected terminal unit which is selected from a plurality of terminal units (10) (50) of different kinds, the radio communication apparatus including receiving means (23) for receiving a radio signal to produce a received signal and adjusting means (24) for adjusting the received signal to produce an adjusted signal, detecting means (31) for detecting the kind of terminal unit selected to produce a signal representative of the selected unit and control means (31) connected to the adjusting (24) and the detecting (31) means for controlling the adjusting means (24) so that the adjusted signal has a level which is selected in accordance with the selected terminal unit and the signal which is representative thereof. A radio communication apparatus as claimed in claim 1, including a first (21) and a second (22) unit, the first unit (21) including the receiving means (23), the adjusting means (24), the detecting means (31), the control means (31), and announcing means (25) connected to the adjusting means (24) for making an announcement representative of the adjusted signal, the second unit (22) being removably connected to the adjusting (24), the detecting (31), and the control (31) means for connecting the selected terminal unit to the adjusting (24), the detecting (31), and the control (31) means. A radio communication apparatus as claimed in claim 2, including a main (48) and a subsidiary (28) antenna, wherein the receiving means (23) is connected to the subsidiary antenna (28), the second unit (22) being removably connected to the main antenna (48). A radio communication apparatus as claimed in claim 3, wherein the second unit (22) is removably connected to the receiving means (23), and the first unit (21) includes an antenna selecting switch (27) connected to the receiving means (23) for selecting one of the main (48) and the subsidiary (28) antennae as a selected antenna, and for connecting the selected antenna to the receiving means (23). A radio communication apparatus as claimed in claim 2, including additional detecting means (31,38,39) for detecting a connection between the first (21) and the second (22) units to produce a connection detection signal, wherein the second unit (22) includes connecting means (43) for connecting a selected terminal unit to the receiving means (23), and main producing means (43) connected to the connecting means (43) for producing a main talk signal, wherein the first unit (21) further includes subsidiary producing means connected to the receiving means (23) for producing a subsidiary talk signal, and wherein selecting means (29) is connected to the additional detecting means (31,38,39) for selecting one of the main and the subsidiary producing means in accordance with the connection detection signal. A radio communication apparatus as claimed in claim 5, wherein the additional detecting means (31,38,39) includes generating means (38) in the second unit (22) for generating a magnetic field, local producing means (39) in the first unit (21) for producing a local signal when the local producing means (39) is placed in the magnetic field, and processing means connected to the local producing means (39) and selecting means (29) for processing the local signal into the connection detection signal. A radio communication apparatus as claimed in claim 1, in which the selected terminal unit includes manually operable adjusting means (13) for manually adjusting the adjusted signal to produce a manually adjusted signal and announcing means (11) connected to the manually adjusting means (13) for providing an audible announcement in accordance with the manually adjusted signal, wherein the control means (31) comprises internal control means (31) connected to the detecting (31) and the first-mentioned adjusting means (24) for controlling the adjusting means (24) so that the predetermined level of the adjusted signal is constant. A radio communication apparatus as claimed in claim 1, in which the selected terminal unit includes manually operable means (53) for producing a control signal for an audible announcement, wherein the control means (31) is connected to the manually operable means (53) for controlling the adjusting means so that the predetermined level of the adjusted signal is adjusted in accordance with both the kind of signal and the audible announcement control signal.

Inventors: MARU TSUGUO, MARU, TSUGUO, MARU, TSUGUO, C/O NEC CORPORATION
Applicants: NIPPON ELECTRIC CO, NEC CORPORATION
Application year: 1990
Main classification: H04Q7
IPC codes: H04B7, H04M1, H04W88