Communication apparatus

Abstract

To provide a radio transmitter-receiver that suppresses undesired power consumption by allowing a user to intentionally control transmission power so as to extend a consecutive operating time and is suitable to ensure' symmetry of communication'.SOLUTION: The radio transceiver reduces the upper limit value of the transmission power by the operation of the operation means, and reduces the reception sensitivity according to the reduced upper limit value of the transmission power. As a result, the user can determine the upper limit value of the transmission power of the wireless transmitter-receiver, and by the user managing the transmission power, the power consumption can be suppressed and the continuous operation time can be extended. Further, the influence of the radio frequency electromagnetic field on the human body can be reduced. Further, it is possible to reduce the degree of collapse of the "symmetry of communication".SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a radio transceiver, and more particularly to a technique for controlling the transmission power of a radio transceiver. [Background technology]

[0002] In recent years, wireless terminals (hereinafter referred to as wireless terminals) in mobile communication systems, such as battery-powered mobile phones and mobile PCs with built-in communication devices, have become widely used, and technological development is underway to utilize various power-saving technologies to extend continuous operating time even as much as possible.

[0003] On the other hand, when looking at the breakdown of power consumption of wireless terminals, a large proportion is consumed by transmission. Conventional wireless terminals determine their transmission power based on the signal strength and quality of the received signal received from a wireless base station (hereinafter referred to as wireless base station) in a mobile communication system.

[0004] As an example of conventional technology, the technology described in Patent Document 1 is a technology that measures the strength of a received signal in wireless communication and determines transmission power.

[0005] [Patent Document 1] Japanese Patent Application Publication No. 07-226710 Summary of the Invention [Problem to be solved by the invention]

[0006] However, conventional wireless terminals do not allow users to intentionally control the transmission power, so when the power is on, users cannot reduce the transmission power to reduce power consumption. As a result, in environments where radio waves from wireless base stations are difficult to reach, wireless terminals transmit at maximum output, consuming more power than the user expected, which is one of the causes of shorter continuous operating time.

[0007] An object of the present invention is to provide a radio transmitter / receiver and its control means that allow a user to intentionally control transmission power, thereby suppressing unwanted power consumption and extending continuous operation time.

[0008] Radio waves emitted from a radio base station with a predetermined transmission power are subjected to propagation loss on the path to the receiver and are received by a radio terminal.

[0009] Similarly, radio waves emitted from a wireless terminal undergo the same amount of propagation loss on the path to the receiver and are received by the wireless base station. In this way, the propagation loss on the transmitting side and the receiving side are equal, so communication is symmetrical.

[0010] Normally, the maximum transmission power of a wireless base station and a wireless terminal is different. Even if the transmission output of a wireless base station and a wireless terminal is different, the system is designed to maintain "communication symmetry" by taking into account the characteristics of the antenna and the noise figure of the receiving section.

[0011] If only the transmission power of the wireless terminal is reduced, the signal received by the wireless base station will be weaker, and "symmetry of communication" will no longer be maintained. In this state, to maintain "symmetry of communication" only on the wireless terminal side, it is sufficient to reduce the receiving sensitivity to match the reduced transmission power of the wireless terminal.

[0012] An object of the present invention is to make it possible to vary the transmission power at the user's will while ensuring "symmetry of communication." [Means for solving the problem]

[0013] [Invention 1] In order to achieve the above object, the wireless transceiver of invention 1 has a transmission power control means and a reception sensitivity control means, and is characterized in that the transmission power control means and the reception sensitivity control means are controlled by a single operation.

[0014] Here, controlling the transmission power control means and the reception sensitivity control means by a single operation means that the operation is performed while the power of the wireless transceiver is on, and does not include, for example, a case where the upper limit value of the transmission power and the reception sensitivity become 0 simultaneously by turning the power from on to off.

[0015] [Invention 2] Furthermore, in order to achieve the above object, the wireless transceiver of Invention 2 is characterized by comprising: means for lowering the upper limit of transmission power by a predetermined operation; and means for lowering reception performance in accordance with the upper limit of transmission power lowered by the predetermined operation.

[0016] With this configuration, since the device is provided with a means for lowering the upper limit of transmission power through a predetermined operation, it is possible to obtain the effect of suppressing power consumption by allowing the user to manage the transmission power, thereby extending the continuous operation time. Also, since the device is provided with a means for lowering reception performance in accordance with the lowered upper limit of transmission power, it is possible to obtain the effect of reducing the degree to which "communication symmetry" is lost.

[0017] [Invention 3] Furthermore, the wireless transceiver of invention 3 is the wireless transceiver described above, characterized in that the reception performance is reception sensitivity.

[0018] [Invention 4] Furthermore, the wireless transceiver of invention 4 is the wireless transceiver described above, characterized in that the reception performance is a reference value for determining whether communication has been established.

[0019] [Invention 5] Furthermore, the wireless transceiver of invention 5 is the wireless transceiver described above, characterized in that the reception performance is a permissible value for an error rate of received data.

[0020] [Invention 6] Furthermore, in order to achieve the above object, the wireless transceiver of Invention 6 is characterized by comprising: means for lowering the upper limit of transmission power by a predetermined operation; and means for notifying the other party of the reception status when the reception performance is lowered or when the reception performance is assumed to be lowered in accordance with the upper limit of transmission power lowered by the predetermined operation.

[0021] With this configuration, since the device is provided with a means for lowering the upper limit of the transmission power by a predetermined operation, the user can manage the transmission power, thereby reducing power consumption and extending the continuous operation time. Also, since the device is provided with a means for notifying the other party of the reception status when the reception performance is lowered or when the reception performance is assumed to be lowered in accordance with the lowered upper limit of the transmission power, for example, if the other party of the communication controls the transmission power etc. based on the reception status of the wireless transmitter / receiver, the effect of reducing the degree to which the "symmetry of communication" is broken can be achieved.

[0022] [Invention 7] Furthermore, the wireless transceiver of invention 7 is the wireless transceiver described above, characterized in that the reception performance is reception sensitivity.

[0023] [Invention 8] Furthermore, the wireless transceiver of invention 8 is the wireless transceiver described above, characterized in that the reception performance is a reference value for determining whether communication has been established.

[0024] [Invention 9] Furthermore, the wireless transceiver of invention 9 is the wireless transceiver described above, characterized in that the reception performance is a permissible value for an error rate of received data.

[0025] [Invention 10] Furthermore, the wireless transceiver of Invention 10 is the wireless transceiver described above, characterized in that, due to the reduced reception sensitivity, communication is established with a partner in wireless transmission and reception at a radio wave intensity stronger than a pre-registered radio wave intensity.

[0026] [Invention 11] Furthermore, the wireless transceiver of Invention 11 is the above-mentioned wireless transceiver, characterized in that the upper limit of the transmission power and the receiving sensitivity can be simultaneously reduced or restored to normal by a control signal generated by the user's specified operation.

[0027] [Invention 12] Furthermore, the wireless transceiver of Invention 12 is the above-mentioned wireless transceiver, characterized in that it can simultaneously lower the upper limit of transmission power and the receiving sensitivity or return them to normal by a control signal generated by transmitting information from the outside and remotely operating it.

[0028] [Invention 13] Furthermore, the wireless transceiver of Invention 13 is the wireless transceiver described above, characterized in that when transmitting to a previously registered other party in information transmission in a state in which the upper limit value of transmission power and the receiving sensitivity are reduced, the reduced upper limit value of transmission power returns to normal.

[0029] [Invention 14] Furthermore, the wireless transceiver of Invention 14 is the wireless transceiver described above, characterized in that when a call arrives from a pre-registered other party in information transmission while the upper limit value of transmission power and receiving sensitivity are reduced, the reduced upper limit value of transmission power returns to normal.

[0030] [Invention 15] Furthermore, the wireless transceiver of Invention 15 is the above-mentioned wireless transceiver, characterized in that when a specific, preset event is detected in a state in which the upper limit value of the transmission power and the receiving sensitivity are reduced, the reduced upper limit value of the transmission power returns to normal.

[0031] Here, the specific event refers to a state in which the reduced upper limit value of transmission power can be automatically restored to normal without any operation by the user.

[0032] For example, when wired earphones are connected, and / or when a wired microphone is connected, and / or when wireless earphones are connected, and / or when a wireless microphone is connected, and / or when the user is in a pre-registered area, and / or when the user is in a pre-registered time period, the reduced upper limit value of the transmission power returns to normal.

[0033] [Invention 16] Furthermore, in order to achieve the above object, the radio transceiver of Invention 16 has a transmission power control means and a reception sensitivity control means, and the transmission power control means and the reception sensitivity control means have a common control signal, and by manipulating the control signal, the radio transceiver can simultaneously lower the upper limit of the transmission power and the reception sensitivity or return them to normal, and by using the lowered reception sensitivity, establish communication with a partner in radio transmission and reception with a radio field strength stronger than a pre-registered radio wave strength, and is characterized in that it has a location detection means and can lower the upper limit of the transmission power or return it to normal when it detects that it is in a pre-registered area.

[0034] [Invention 17] Furthermore, the wireless transceiver of invention 17 is the wireless transceiver described above, characterized in that the receiving sensitivity is controlled in conjunction with the transmitting output.

[0035] [Invention 18] Furthermore, the wireless transceiver of invention 18 is the wireless transceiver described above, characterized in that the sensitivity is linked to the output. [Effects of the Invention]

[0036] According to the present invention, the user can determine the upper limit of the transmission power of the wireless transceiver, and by managing the transmission power, the power consumption can be reduced, which can extend the continuous operation time. Also, the effect of the radio frequency electromagnetic field on the human body can be weakened. [Brief explanation of the drawings]

[0037] [Figure 1]1 is a diagram showing a basic configuration of a wireless transceiver according to a first embodiment of the present invention. [Figure 2] FIG. 10 is a diagram illustrating a basic configuration of a wireless transceiver according to a second embodiment of the present invention. [Figure 3] FIG. 10 is a diagram illustrating a basic configuration of a wireless transceiver according to a third embodiment of the present invention. [Figure 4] FIG. 10 is a diagram showing a basic configuration of a wireless transceiver according to a fourth embodiment of the present invention. [Figure 5] FIG. 10 is a diagram illustrating a basic configuration of a wireless transceiver according to a fifth embodiment of the present invention. [Figure 6] 3 is a flowchart showing a basic operation of the wireless transceiver according to the embodiment of the present invention. [Figure 7] FIG. 10 is a diagram showing a display example of a wireless transceiver according to a second embodiment of the present invention. [Figure 8] FIG. 10 is a diagram showing a display example of a wireless transceiver according to a second embodiment of the present invention. [Figure 9] FIG. 10(a) is a diagram showing the transmission power characteristics of a conventional wireless terminal device, and FIG. 10(b) is a diagram showing the transmission power characteristics of a wireless transceiver according to a second embodiment. [Figure 10] FIG. [Figure 11] 1 is a circuit example of a sensitivity controller. [Figure 12] 1 is a circuit example of a transmission power controller. [Figure 13] 10 is a circuit example of a control signal generating unit. [Figure 14] 10 is a circuit example of a control signal generating unit. [Figure 15] 10 is a circuit example of a determination unit for establishing communication; [Figure 16] 10 is a circuit example of a transmission power determination unit using a level limiter. [Figure 17] 10 is a circuit example of a transmission power determination unit using a subtractor. [Figure 18] 1 is a circuit example of a sensitivity converter. [Figure 19] 10 is a circuit example of a determination unit for determining whether analog communication has been established, which includes a built-in reference value generator. [Figure 20] 10 is a circuit example of a digital communication establishment determination unit with a built-in reference value generator. [Figure 21] (a) to (c) are diagrams showing the transmission power characteristics, reception sensitivity characteristics, and reception strength characteristics of a conventional wireless terminal device, and (d) to (f) are diagrams showing the transmission power characteristics, reception sensitivity characteristics, and reception strength characteristics of a conventional wireless terminal device when only the upper limit value of the transmission power is reduced. [Figure 22] 1A to 1C are diagrams showing the transmission power characteristics, reception sensitivity characteristics, and reception strength characteristics of a conventional wireless terminal device, and 1D to 1F are diagrams showing the transmission power characteristics, reception sensitivity characteristics, and reception strength characteristics of a wireless transceiver according to a first embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0038] The embodiment of the present invention The relationship between a mobile communication system and an embodiment of the present invention will be described below.

[0039] A mobile communication system that connects mobile phones and mobile PCs with built-in communication devices consists of at least a wireless terminal device, a "wireless base station that is the other party in wireless transmission and reception" (hereinafter referred to as a wireless base station), a public communication network, and a "terminal device that is the other party in information transmission."

[0040] In this mobile communication system, when you try to establish communication from your wireless terminal to the "terminal that is the other party in the information transmission," your wireless terminal will connect to the "terminal that is the other party in the information transmission" via the "wireless base station that is the other party in the wireless transmission and reception," through the public communication network.

[0041] The present invention is a technology that can be widely applied not only to wireless terminals in mobile communication systems and wireless base stations in mobile communication systems but also to point-to-point wireless communication, etc. However, the wireless transceivers according to the first to fifth embodiments of the present invention described below will be explained as examples of applying the present invention to wireless terminals in mobile communication systems.

[0042] In the embodiment of the present invention, the conditions indicated by the expressions "normal" and "lower than normal" with respect to transmission power and reception sensitivity are defined below.

[0043] In conventional mobile communication systems, the transmission power of a wireless terminal cannot be intentionally changed to a desired value by the user; instead, the strength of the radio waves received from a wireless base station is measured, and the wireless base station and wireless terminal determine the transmission power of the wireless terminal based on the results.

[0044] In an embodiment of the present invention, the transmission power that has not been changed by the user is referred to as "normal transmission power," whereas the transmission power that has been intentionally changed lower by the user is referred to as "transmission power lower than normal."

[0045] [First embodiment] A radio transceiver according to a first embodiment of the present invention will be described below. Fig. 1 is a diagram showing the basic configuration of the radio transceiver according to the first embodiment.

[0046] The configuration of this wireless transceiver and the operation of each part are explained below. This wireless transceiver is composed of an "antenna" 111, a "receiving part" 410, a "transmitting part" 470, a "control signal generating part" 450, and an "operating means" 114.

[0047] The "receiving section" 410 comprises at least a "band limiter" 121, a "sensitivity controller" 122, an "automatic gain control amplifier" 123, a "channel selector" 126, and a "demodulator" 128.

[0048] A "received signal" 331 received by an "antenna" 111 is input to a "receiving unit" 410. A "demodulated signal" 332 is output from the "receiving unit" 410. The "demodulated signal" 332 includes "information transmitted by the base station."

[0049] The “sensitivity controller” 122 can vary the receiving sensitivity according to the “correction control signal” 352 from the “control signal generator” 450 .

[0050] An example circuit of the "sensitivity controller" 122 is shown in Fig. 11. The "sensitivity controller" 122 can be configured, for example, as shown in Fig. 11(a). In the example of Fig. 11(a), the "sensitivity controller" 122 is configured to include a "first capacitor" having one end connected to the "band limiter" 121, a "PIN diode" 564 having an anode terminal connected to the other end of the "first capacitor" and a cathode terminal grounded, a "resistance element" having one end to which the "correction control signal" 352 is input, a "coil" having one end connected to the other end of the "resistance element" and the other end connected to the anode terminal of the "PIN diode" 564, and a "second capacitor" having one end connected to the anode terminal of the "PIN diode" 564 and the other end connected to the "automatic gain control amplifier" 123.

[0051] The "sensitivity controller" 122 can also be configured as shown in Fig. 11(b), for example. In the example of Fig. 11(b), the "sensitivity controller" 122 includes a "first capacitor" having one end connected to the "band limiter" 121, a "second capacitor" having one end grounded, a "first resistor" having one end grounded, a "second resistor" having one end inputting a "correction control signal" 352, a "dual gate field effect transistor" having a first gate terminal G1 connected to the other end of the "first capacitor" and a second gate terminal G2 connected to the other ends of the "second capacitor", the "first resistor" and the "second resistor", and a "dual gate field effect transistor" having one end connected to a source terminal S of the "dual gate field effect transistor". the other end connected to the "power supply" VDD; a "fourth capacitor" having one end connected to the "power supply" VDD and the other end grounded; a "fifth capacitor" having one end connected to the drain terminal D of the "dual gate field effect transistor" and the other end connected to the "automatic gain control amplifier" 123;

[0052] The “transmitter” 470 comprises at least a “carrier generator” 171 , a “modulator” 172 , and a “transmission power controller” 173 .

[0053] A "modulated signal" 374 containing "information to be transmitted to the other party" is input to a "transmitting unit" 470. The "transmitting unit" 470 generates a "transmitting signal" 375 and outputs it to an "antenna" 111.

[0054] The 'transmission power controller' 173 can vary the transmission power according to the 'corrected control signal' 352 from the 'control signal generator' 450 .

[0055] An example circuit of the "transmission power controller" 173 is shown in Fig. 12. The "transmission power controller" 173 can be configured as shown in Fig. 12(a). In the example of Fig. 12(a), the "transmission power controller" 122 is configured to include: a "first capacitor" having one end connected to the "modulator" 172; a "PIN diode" 564 having an anode terminal connected to the other end of the "first capacitor" and a cathode terminal grounded; a "resistance element" having one end to which the "correction control signal" 352 is input; a "coil" having one end connected to the other end of the "resistance element" and the other end connected to the anode terminal of the "PIN diode" 564; a "second capacitor" having one end connected to the anode terminal of the "PIN diode" 564; and a "power amplifier" 566 having an input terminal connected to the other end of the "second capacitor" and outputting a "transmission signal" 375 from an output terminal.

[0056] The "transmission power controller" 173 can be configured as shown in Fig. 12(b). In the example of Fig. 12(b), the "transmission power controller" 122 is configured to include a "variable gain power amplifier" 567 that receives the output signal from the "modulator" 172 and the "correction control signal" 352 from its input terminal and outputs a "transmission signal" 375 from its output terminal.

[0057] The “operation means” 114 generates an “operation signal” 315 based on an operation performed by a user or the like, and outputs it to the “control signal generation section” 450 .

[0058] An "operation signal" 315 from the "operation means" 114 is input to a "control signal generating unit" 450. The "control signal generating unit" 450 outputs a "correction control signal" 352 determined based on the state of the "operation signal" 315. The "control signal generating unit" 450 outputs the generated "correction control signal" 352 to both the "transmitting unit" 470 and the "receiving unit" 410.

[0059] In other words, the "transmitter" 470 and the "receiver" 410 are controlled by a single operation from the "operation means" 114.

[0060] An example of the circuit of the "control signal generating section" 450 is shown in Fig. 13. The "control signal generating section" 450 can be configured as shown in Fig. 13(a). In the example of Figure 13(a), the "control signal generating unit" 450 is configured to include a "first resistor element" one end connected to the "power supply" VDD, a "second resistor element" one end connected to the "power supply" VDD, a "flip-flop" 577 having a set terminal S connected to the other end of the "first resistor element" and a reset terminal R connected to the other end of the "second resistor element", an "analog switch" 578 ​​having a control terminal connected to the output terminal Q of the "flip-flop" 577, a "third resistor element" one end connected to the "power supply" VDD and the other end connected to one end of the "analog switch" 578, a "fourth resistor element" one end connected to one end of the "analog switch" 578 ​​and the other end grounded, a "fifth resistor element" one end connected to the other end of the "analog switch" 578 ​​and the other end grounded, and a "voltage follower amplifier" 551 having an input terminal connected to one end of the "analog switch" 578 ​​and outputting a "correction control signal" 352 from an output terminal.

[0061] The "control signal generating unit" 450 can be configured as shown in Fig. 13(b). In the example of Fig. 13(b), the "control signal generating unit" 450 includes a "first resistor element" having one end connected to the "power supply" VDD, a "second resistor element" having one end connected to the "power supply" VDD, a "flip-flop" 577 having a set terminal S connected to the other end of the "first resistor element" and a reset terminal R connected to the other end of the "second resistor element", a first "three-state buffer" 576 having an output enable terminal OE connected to an output terminal Q of the "flip-flop" 577 and outputting a "correction control signal" 352 from the output terminal, n+1 "first switch elements" having one end connected to each of the n+1 input terminals of the first "three-state buffer" 576 and the other end grounded, and a "second resistor element" having one end connected to the "power supply" VDD. a second "three-state buffer" 576 having an output enable terminal OE connected to an inverting output terminal Q of the "flip-flop" 577 and outputting a "correction control signal" 352 from its output terminal; n+1 "second switch elements" having one end connected to each of the n+1 input terminals of the second "three-state buffer" 576 and the other end grounded; and n+1 "fourth resistor elements" having one end connected to the "power supply" VDD and the other end connected to each of the n+1 input terminals of the second "three-state buffer" 576.

[0062] In the examples of Figures 13(a) and (b), the "operation means" 114 is configured to have a "first switch element" having one end connected to the set terminal S of the "flip-flop" 577 and the other end grounded, and a "second switch element" having one end connected to the reset terminal R of the "flip-flop" 577 and the other end grounded.

[0063] The operation of this wireless transceiver when its transmission power is "normal transmission power" will be described below.

[0064] When the transmission power of this wireless transceiver is "normal transmission power," the operation is the same as that of a conventional wireless terminal.

[0065] When the transmission power of this wireless transceiver is the "normal transmission power," the "control signal generating unit" 450 generates a "corrected control signal" 352 with a value that maintains the "normal transmission power" and "normal receiving sensitivity," and outputs this to the "transmitting unit" 470 and the "receiving unit" 410.

[0066] Since the "transmission power controller" 173, which is a component of the "transmission unit" 470, receives the "correction control signal" 352 with a value that maintains the "normal transmission power," the "transmission unit" 470 outputs the "transmission signal" 375 at the "normal transmission power."

[0067] Furthermore, since the "sensitivity controller" 122, which is a component of the "receiving unit" 410, receives a "correction control signal" 352 with a value that maintains the "normal receiving sensitivity," the "receiving unit" 410 generates a "demodulated signal" 332 with the "normal receiving sensitivity."

[0068] The following explains the problems that occur when the transmission power is lowered. The wireless transceiver determines the transmission power depending on the strength of the radio waves received from the wireless base station.

[0069] If the radio wave received from the radio base station is strong, the radio transceiver reduces the transmission power. Conversely, if the radio wave received from the radio base station is weak, the radio transceiver increases the transmission power.

[0070] Normally, a wireless transceiver transmits with the minimum necessary transmission power. For example, when a wireless transceiver can receive radio waves from a wireless base station, simply reducing the transmission power of the wireless transceiver will prevent the signal from reaching the wireless base station and communication will become impossible. Also, the "symmetry of communication" between the transmission output and reception sensitivity of the wireless transceiver as seen from the wireless base station will be lost. For this reason, the wireless base station and the base station network will Normal operation will not be possible.

[0071] These problems and the method for solving them will be described in more detail below in comparison with the conventional method.

[0072] Figures 21(a) to (c) are diagrams showing the transmission power characteristics, reception sensitivity characteristics, and reception strength characteristics of a conventional wireless terminal device, and Figures 21(d) to (f) are diagrams showing the transmission power characteristics, reception sensitivity characteristics, and reception strength characteristics of a conventional wireless terminal device when only the upper limit value of the transmission power is reduced.

[0073] Figures 22(a) to (c) are diagrams showing the transmission power characteristics, reception sensitivity characteristics, and reception strength characteristics of a conventional wireless terminal device, and Figures 22(d) to (f) are diagrams showing the transmission power characteristics, reception sensitivity characteristics, and reception strength characteristics of a wireless transceiver according to this embodiment.

[0074] The vertical axis 800 in Figures 21(a), (d) and 22(a), (d) represents transmission power, the vertical axis 801 in Figures 21(b), (e) and 22(b), (e) represents reception sensitivity, and the vertical axis 802 in Figures 21(c), (f) and 21(c), (f) represents reception intensity. Also, the horizontal axis 803 in each graph in Figures 21 and 22 represents propagation loss (≈ distance) between a conventional wireless terminal device (or a wireless transceiver according to this embodiment) and a wireless base station.

[0075] In a conventional wireless terminal, as shown in Fig. 21(a), transmission power is controlled so that it increases as the propagation loss between the wireless terminal and the wireless base station increases (i.e., as the radio waves received from the wireless base station become weaker). When the transmission power reaches the maximum transmission power 804 that the wireless terminal can exert, it remains constant at maximum transmission power 804, and it becomes unable to transmit signals to the wireless base station when the propagation loss becomes slightly higher than the point at which it reached maximum transmission power 804. On the other hand, as shown in Fig. 21(b), the reception sensitivity is set to the maximum reception sensitivity 805 that the wireless terminal can exert regardless of the propagation loss, so that as the reception strength increases, it decreases from maximum reception strength 815 as the propagation loss increases, as shown in Fig. 21(c), and when it drops to allowable value 806, it becomes unable to receive signals from the wireless base station.

[0076] In this state, the range 807 in which the wireless terminal can transmit signals to the wireless base station matches the range 808 in which the wireless terminal can receive signals from the wireless base station, so "symmetry of communication" is maintained. This is because the system is designed to maintain "symmetry of communication" by taking into account the antenna characteristics and the noise figure of the receiving section. Therefore, when the propagation loss exceeds ranges 807 and 808 and increases to ranges 809 and 810, the wireless terminal will no longer be able to establish communication with the wireless base station and will display "out of range."

[0077] In contrast, if only the upper limit of transmission power is reduced to a certain value 811, the transmission power remains constant at this certain value 811 once it reaches the certain value 811, as shown in FIG. 21(d), and the wireless terminal device is no longer able to transmit signals to the wireless base station when the propagation loss becomes slightly higher than the point at which the transmission power reaches the certain value 811. Therefore, the range 812 in which the wireless terminal device can transmit signals to the wireless base station is smaller than when the upper limit of transmission power is not reduced. On the other hand, since the reception sensitivity is set to the maximum reception sensitivity 805 regardless of the propagation loss as shown in FIG. 21(e), the reception strength decreases from the maximum reception strength 815 as the propagation loss increases, as shown in FIG. 21(f), and when it drops to the allowable value 806, the wireless terminal device is no longer able to receive signals from the wireless base station. Therefore, the range 808 in which the wireless terminal device can receive signals from the wireless base station is the same as when the upper limit of transmission power is not reduced.

[0078] In this state, the range 812 in which the wireless terminal can transmit signals to the wireless base station does not match the range 808 in which the wireless terminal can receive signals from the wireless base station, and so "symmetry of communication" is lost. In other words, when the propagation loss is in a range that exceeds range 812 but does not exceed range 808, a one-way communication state occurs in which signals cannot be transmitted to the wireless base station but can be received from the wireless base station, and the wireless terminal cannot make calls to the wireless base station even though it does not display "out of service area." This not only confuses users, but also, as mentioned above, the wireless base station and base station network cannot operate normally with the wireless terminal.

[0079] Therefore, in the wireless transceiver according to this embodiment, when the upper limit of transmission power is lowered to a fixed value 811 by operating the "operation means" 114 as shown in Fig. 22(d), the receiving sensitivity is lowered to a fixed value 813 in accordance with the lowered upper limit of transmission power 811 as shown in Fig. 22(e). For example, when the upper limit of transmission power is lowered from maximum transmission power 804 (e.g., 1 [W]) to a fixed value 811 (e.g., 0.1 [W]), the receiving sensitivity is lowered from maximum receiving sensitivity 805 (e.g., 0 [dB]) to a fixed value 813 (e.g., -10 [dB]). If the receiving sensitivity is lowered, the receiving strength also decreases from a fixed value 816, which is lower than maximum receiving strength 815 by a predetermined value (corresponding to the difference between maximum receiving sensitivity 805 and fixed value 813) as the propagation loss increases, as shown in Fig. 22(f). When the receiving strength drops to the allowable value 806, it becomes impossible to receive signals from the wireless base station. Therefore, the range of reception strength is narrowed, and the range 814 in which the wireless transceiver can receive signals from the wireless base station is narrower than when the reception sensitivity is not reduced.

[0080] As a result, the range 812 in which the wireless transceiver can transmit signals to the wireless base station and the range 814 in which the wireless transceiver can receive signals from the wireless base station are the same, thereby maintaining "symmetry of communication."

[0081] The receiving sensitivity can be reduced according to the upper limit of the transmission power, but in this case, it is preferable to reduce the sensitivity so that the range (reception range) in which the wireless transceiver can receive signals from the wireless base station matches the range (transmission range) in which the wireless transceiver can transmit signals to the wireless base station. However, the reception range and the transmission range do not necessarily have to match, and as long as the mismatch between the reception range and the transmission range can be reduced compared to when the receiving sensitivity is not reduced at all, the degree to which the "symmetry of communication" is broken can be reduced. Therefore, when the upper limit of the transmission power is reduced, it can be said that the receiving sensitivity should be reduced so that the reception range matches the transmission range or the mismatch is reduced.

[0082] Next, the operation of the wireless transceiver according to this embodiment when the transmission power is changed to "transmission power lower than normal" and the operation to prevent the above-mentioned malfunction will be described below using an example in which a variable attenuator is used as the "sensitivity controller" 122.

[0083] Here, suppose that the user manually attempts to reduce the transmission power, which has been increasing or decreasing within a predetermined range as a normal operation, to 1 / 10.

[0084] When the user operates the “operation means” 114 , the “correction control signal” 352 is input from the “control signal generator” 450 to the “sensitivity controller” 122 (variable attenuator) and the “transmission power controller” 173 .

[0085] Here, the "correction control signal" 352 is a value that reduces the transmission power to 1 / 10. The "transmission power controller" 173 sets the transmission power to 1 / 10 of the original maximum transmission power.

[0086] The "sensitivity controller" 122 (variable attenuator) sets the attenuation rate to 1 / 10. Therefore, the wireless transceiver according to this embodiment can switch the transmission power to "lower than normal transmission power" or return it to "normal transmission power" by operation performed by the user, and in conjunction with the switching of the transmission power, the reception sensitivity also switches to "lower than normal reception sensitivity" or returns to "normal reception sensitivity."

[0087] The following describes a method for lowering the receiving sensitivity of the "receiving section" 410. The "sensitivity controller" 122, which is a component of the "receiving section" 410, can be implemented by a variable attenuator and a variable amplifier.

[0088] In addition to using these, the reception sensitivity of the 'receiving section' 410 can be lowered by narrowing the gain variable range of the 'automatic gain control amplifier' 123 .

[0089] In this way, in this embodiment, the wireless transceiver lowers the upper limit of the transmission power by operating the "operation means" 114, and lowers the reception sensitivity in accordance with the lowered upper limit of the transmission power.

[0090] This allows the user to determine the upper limit of the transmission power of the wireless transceiver, and by managing the transmission power, the power consumption can be reduced and continuous operation time can be extended. It also weakens the effect of radio frequency electromagnetic fields on the human body. Furthermore, it reduces the degree to which "communication symmetry" is broken.

[0091] Second Embodiment A radio transceiver according to a second embodiment of the present invention will be described below. Fig. 2 is a diagram showing the basic configuration of the radio transceiver according to the second embodiment.

[0092] The configuration of this wireless transceiver and the operation of each section are explained below. This wireless transceiver is composed of an "antenna" 111, a "receiving section" 420, a "communication establishment determining section" 430, a "transmitting power determining section" 460, a "transmitting section" 470, a "control signal generating section" 450, and an "operating means" 114.

[0093] The "receiving section" 420 comprises at least a "band limiter" 121, an "automatic gain control amplifier A" 124, an "automatic gain control amplifier B" 125, a "channel selector" 126, a "demodulator" 128, and a "receiving level generator" 129.

[0094] A "received signal" 331 received by an "antenna" 111 is input to a "receiving unit" 420. A "demodulated signal" 332 is output from the "receiving unit" 420. The "demodulated signal" 332 includes "information transmitted by the base station."

[0095] The "reception level generator" 129 converts the strength and quality of the "reception signal" 331 input to the "reception unit" 420 into a "reception level signal" 335 and outputs it. The "reception level generator" 129 outputs the "reception level signal" 335 to the "communication establishment determination unit" 430 and the "transmission power determination unit" 460 simultaneously.

[0096] It should be noted that both the "automatic gain control amplifier A" 124 and the "automatic gain control amplifier B" 125 are not essential, and implementation is possible with at least one "automatic gain control amplifier."

[0097] The "communication establishment determination unit" 430 is composed of at least a "level comparator" 141. The "reception level signal" 335 from the "receiving unit" 420 and the "corrected control signal" 352 from the "control signal generating unit" 450 are input to the "communication establishment determination unit" 430.

[0098] The 'communication establishment determination unit' 430 compares the value of the 'receiving level signal' 335 with the value of the 'corrected control signal' 352 and determines the state of the 'communication establishment determination signal' 343 .

[0099] The "communication establishment determination signal" 343 is output in either the "communication establishment possible" or "communication establishment not possible" state.

[0100] An example circuit of the "unit for determining whether communication is established" 430 is shown in Fig. 15. The "unit for determining whether communication is established" 430 can be configured as shown in Fig. 15(a). In the example of Fig. 15(a), the "unit for determining whether communication is established" 430 is configured with a "level comparator" 141. The "level comparator" 141 is configured with a "comparator" 553 which is an analog circuit. The "comparator" 553 receives the "received level signal" 335 from a non-inverting input terminal, receives the "correction control signal" 352 from an inverting input terminal, and outputs the "communication establishment determination signal" 343 from an output terminal.

[0101] The "unit for determining whether communication has been established" 430 can be configured as shown in Fig. 15(b). In the example of Fig. 15(b), the "unit for determining whether communication has been established" 430 is configured to include a "level comparator" 141. The "level comparator" 141 is configured to include an "A / D converter" 568 that receives and A / D-converts the "received level signal" 335, and a weighted "comparator" 558 that uses a logic circuit. The "comparator" 558 receives the A / D-converted "received level signal" 335 from a first input terminal, receives the "corrected control signal" 352 (digital signal) from a second input terminal, and outputs a "communication establishment determination signal" 343 from an output terminal.

[0102] The 'transmission power determination unit' 460 comprises at least a 'level calculator' 163 and a 'level limiter' 161 .

[0103] The "reception level signal" 335 from the "reception unit" 420 and the "control A “corrected control signal” 352 from a “signal generating section” 450 is input to a “transmission power determining section” 460 .

[0104] The “level calculator” 163 of the “transmission power determination unit” 460 determines the transmission power from the value of the “reception level signal” 335 .

[0105] The "level limiter" 161 checks whether the transmission power determined by the "level calculator" 163 exceeds the upper limit value based on the value of the "correction control signal" 352, and if it does, changes the transmission power to the upper limit value. This is output to the "transmitter" 470 as the "transmission power control signal" 362.

[0106] That is, since an upper limit is imposed according to the value of the "correction control signal" 352, an upper limit-limited "transmission power control signal" 362 is output, and the transmission power is suppressed to a desired value or less.

[0107] 16 and 17 show circuit examples of the "transmission power determination unit" 460. The "transmission power determination unit" 460 can be configured as shown in FIG. 16(a). In the example of FIG. 16(a), the "transmission power determination unit" 460 is configured to include a "level limiter" 161 and a "level calculator" 163. The "level calculator" 163 is configured to include an "inverting amplifier" 533 which is an analog circuit. The "inverting amplifier" 533 receives the "reception level signal" 335, amplifies it, and outputs it. The "level limiter" 161 is configured to include a "level limiter" 559 which is an analog circuit. The "level limiter" 559 receives the amplified "reception level signal" 335 from its input terminal, receives the "corrected control signal" 352 as a "level limit reference voltage" 717, and outputs a "transmission power limit signal" 362 from its output terminal.

[0108] The "transmission power determination unit" 460 can be configured as shown in FIG. 16(b). In the example of FIG. 16(b), the "transmission power determination unit" 460 is configured with a "level limiter" 161 and a "level calculator" 163. The "level calculator" 163 is configured with an "inverting amplifier" 533 using an analog circuit. The "inverting amplifier" 533 receives the "reception level signal" 335, amplifies it, and outputs it. The "level limiter" 161 is configured with a "D / A converter" 569 that receives the "correction control signal" 352 (digital signal) and performs D / A conversion, and a "level limiter" 559 using an analog circuit. The "level limiter" 559 receives the amplified "reception level signal" 335 from its input terminal, receives the D / A converted "correction control signal" 352 as a "level limit reference voltage" 717, and outputs the "transmission power limit signal" 362 from its output terminal.

[0109] The "transmission power determination unit" 460 can be configured as shown in Fig. 17(a). In the example of Fig. 17(a), the "transmission power determination unit" 460 is configured to have a "subtractor" 555 which is an analog circuit. The "subtractor" 555 receives the "reception level signal" 335 and the "correction control signal" 352, subtracts the "correction control signal" 352 from the "reception level signal" 335, and outputs the result of the subtraction, the "transmission power control signal" 362, from an output terminal.

[0110] The "transmission power determination unit" 460 can be configured as shown in Fig. 17(b). In the example of Fig. 17(b), the "transmission power determination unit" 460 is configured to include a "D / A converter" 569 that receives the "correction control signal" 352 (digital signal) and performs D / A conversion, and a "subtractor" 555 that is an analog circuit. The "subtractor" 555 receives the "reception level signal" 335 and the D / A converted "correction control signal" 352, subtracts the "correction control signal" 352 from the "reception level signal" 335, and outputs the result of the subtraction, the "transmission power control signal" 362, from an output terminal.

[0111] The "transmission power determination unit" 460 can be configured as shown in Fig. 17(c). In the example of Fig. 17(c), the "transmission power determination unit" 460 is configured to include an "A / D converter" 568 that receives the "reception level signal" 335 and performs A / D conversion, a "subtractor" 557 using a logic circuit, and a "D / A converter" 569 that D / A converts the output signal from the "subtractor" 557 and outputs the "transmission power control signal" 362. The "subtractor" 557 receives the A / D converted "reception level signal" 335 and "correction control signal" 352 (digital signal), subtracts the "correction control signal" 352 from the "reception level signal" 335, and outputs the result of the subtraction from an output terminal.

[0112] The “transmitter” 470 comprises at least a “carrier generator” 171 , a “modulator” 172 , and a “transmission power controller” 173 .

[0113] A "modulated signal" 374 containing "information to be delivered to the other party" is input to a "transmitting unit" 470. The "transmitting unit" 470 generates a "transmitting signal" 375 and outputs it to an "antenna" 111.

[0114] The "transmission power controller" 173 can vary the transmission power according to the "transmission power control signal" 362 from the "transmission power determination unit" 460. An example of the circuit of the "transmission power controller" 173 is shown in FIG.

[0115] The “operation means” 114 generates an “operation signal” 315 based on the operation performed, and outputs it to the “control signal generation section” 450 .

[0116] An "operation signal" 315 from the "operation means" 114 is input to a "control signal generating unit" 450. The "control signal generating unit" 450 determines the value of a "corrected control signal" 352 to be generated based on the state of the "operation signal" 315. The "control signal generating unit" 450 outputs the generated "corrected control signal" 352 to a "transmission power determining unit" 460 and a "unit for determining whether communication has been established" 430. An example circuit of the "control signal generating unit" 450 is as shown in FIG. 13.

[0117] The following explains the role of the "reception level generator" 129. The "reception level generator" 129 obtains information such as signal strength and signal error rate from the "automatic gain control amplifier A" 124, "automatic gain control amplifier B" 125, and "demodulator" 128 that constitute the "reception unit" 420, and generates the "reception level signal" 335 based on the results of evaluating this information.

[0118] A single piece of information such as signal strength or signal error rate may be used, or multiple pieces of information may be used. In this case, the multiple pieces of information may be input in parallel or may be added together.

[0119] The role of the "communication establishment determination unit" 430 will be explained below. The radio wave transmitted from the radio base station is received by the radio transceiver, and a "reception level signal" 335 corresponding to the strength of the received signal is output. The "communication establishment determination unit" 430 determines whether the radio wave with transmission output limited by the "correction control signal" 352 can reach the radio base station and establish communication, judging from the value of the "reception level signal" 335.

[0120] Therefore, if the state of the "communication establishment determination signal" 343 is "communication establishment not established", there is a risk that the radio waves transmitted by the wireless transceiver will not be received by the wireless base station, so even if there is a request to start communication from the wireless base station, the wireless transceiver can be prevented from starting communication.

[0121] In addition, determining whether communication is established based on the "reception level signal" 335 and restricting communication to wireless base stations with reception signals weaker than the pre-registered radio wave strength is the same as reducing reception sensitivity and not communicating with wireless base stations with weak reception signal levels.

[0122] The operation of this wireless transceiver when its transmission power is "normal transmission power" will be described below.

[0123] When the transmission power of this wireless transceiver is "normal transmission power," the operation is the same as that of a conventional wireless terminal.

[0124] When the transmission power of this wireless transceiver is the "normal transmission power," the "control signal generating unit" 450 generates a "corrected control signal" 352 with a value that maintains the "normal transmission power" and the "normal receiving sensitivity," and outputs this to the "transmission power determining unit" 460 and the "communication establishment determining unit" 430.

[0125] The 'transmission power determination unit' 460 determines the value of the 'transmission power control signal' 362 to be output to the 'transmitter' 470 based on the value of the 'reception level signal' 335 .

[0126] That is, when the value of "reception level signal" 335 becomes high, it is determined that the wireless base station is located close by, and in order to suppress transmission power, the value of "transmission power control signal" 362 is lowered. Conversely, when the value of "reception level signal" 335 becomes low, it is determined that the wireless base station is located far away, and the value of "transmission power control signal" 362 is raised.

[0127] At this time, the "corrected control signal" 352 input to the "transmission power determination unit" 460 is a value that maintains the "normal transmission power." Because this value is the value of the "maximum transmission power," the value of the "transmission power control signal" 362 that the "transmission power determination unit" 460 outputs to the "transmitter" 470 can be controlled up to the value of the "maximum transmission power."

[0128] At this time, the "corrected control signal" 352 input to the "communication establishment determination unit" 430 is a value that maintains the "normal receiving sensitivity," so the "communication establishment determination unit" 430 determines whether the "demodulated signal" 332 at that time is from a wireless base station that can be reached when this wireless transceiver emits radio waves at the "maximum transmission power," and outputs the state of the "communication establishment determination signal" 343 as either "communication establishment possible" or "communication establishment not possible." This is the same operation as that of a conventional wireless terminal device.

[0129] In this state, conventional wireless terminal devices do not allow users to change the transmission power to "transmission power lower than normal," and it is not possible for users to reduce power consumption by reducing the transmission power depending on the situation.

[0130] Furthermore, if the transmission power is simply lowered in some way, it is expected that "even though the radio waves arriving from the radio base station will arrive with the same strength as before, the radio waves emitted from the radio transceiver will become weaker and will not be able to reach the radio base station."

[0131] Here, the operation of the wireless transceiver according to this embodiment when the transmission power is changed to "transmission power lower than normal" and the operation to prevent the above-mentioned problem will be described below.

[0132] For example, when a user operates the wireless transceiver to lower the transmission power than normal, the “control signal generating unit” 450 outputs a “corrected control signal” 352 having values ​​that set “lower-than-normal transmission power” and “lower-than-normal receiving sensitivity” to both the “transmission power determining unit” 460 and the “communication establishment determining unit” 430.

[0133] That is, the "transmission power determination unit" 460 and the "communication establishment determination unit" 430 are controlled by a single operation.

[0134] The 'transmission power determination unit' 460 outputs to the 'transmitter' 470 a 'transmission power control signal' 362 whose value is within the range of the upper limit value according to the value of the 'correction control signal' 352 .

[0135] Therefore, the "transmitter" 470 outputs the "transmitted signal" 375 at a power within the upper limit range.

[0136] At the same time, the 'control signal generating section' 450 outputs the 'corrected control signal' 352 to the 'communication establishment determining section' 430 .

[0137] If the received signal level from the wireless base station is stronger than the value indicated by the "corrected control signal" 352, the "communication establishment determination unit" 430 sets the state of the "communication establishment determination signal" 343, which determines whether communication can be established, to "communication establishment possible."

[0138] When a radio transmitter / receiver emits a signal at a "transmission power lower than normal," if it receives a relatively weak radio wave from a radio base station located in a position where the radio wave cannot reach, the value of the "reception level signal" 335 output by the "receiving unit" 420 will be weaker than the value indicated by the "corrected control signal" 352, and therefore the "communication establishment determination unit" 430 will set the state of the "communication establishment determination signal" 343 to "communication establishment not established."

[0139] Here, the "communication establishment determination signal" 343 may be output when communication starts, or may be output when the "transmission signal" 375 reaches the upper limit of the "transmission power lower than normal."

[0140] It should be noted that the "value indicated by the 'correction control signal' 352" is not a positive or negative logic in the circuit, but a value obtained by relatively comparing "normal transmission power" and "transmission power lower than normal."

[0141] As described above, by referring to the "communication establishment judgment signal" 343, the radio transmitter / receiver can detect radio waves from a radio base station within the range of the radio waves emitted by the radio transmitter / receiver with "lower than normal transmission power." Since communication is only performed via this, the aforementioned problem of "the radio waves arriving from the radio base station will arrive with the same strength as before, but the radio waves emitted from this radio transceiver will become weaker and will not be able to reach the radio base station" will no longer occur.

[0142] The above operation is summarized as a flowchart in Figure 6. Also, the transmission power characteristics are shown in Figure 9.

[0143] FIG. 9(a) is a diagram showing the transmission power characteristics of a conventional wireless terminal device, and FIG. 9(b) is a diagram showing the transmission power characteristics of the wireless transceiver according to this embodiment.

[0144] 9, 994 represents the transmission power characteristic without correction control, 995 represents the transmission power characteristic when corrected by -10 [dB], and 996 represents the transmission power characteristic when corrected by -20 [dB].

[0145] As described above, the wireless transceiver according to this embodiment is a wireless transceiver that allows the user to change the upper limit of the transmission power of the wireless transceiver, and by changing the reception sensitivity in conjunction with this, it is possible to suppress problems that may occur as a result of lowering the maximum transmission power.

[0146] Although the actual "reception level signal" 335 does not decrease, a "communication establishment determination signal" 343 indicating that the "reception level signal" 335 has decreased is output to the subsequent stage.

[0147] This allows the user to reduce power consumption by lowering the transmission power depending on the situation.

[0148] Up to this point, the explanation has been given in terms of changing the transmission power value of a wireless transceiver by having the user use a selector switch to select either "normal transmission power" or "transmission power lower than normal."

[0149] However, by using a multi-stage selector switch or the like, it is possible to select values ​​in stepped increments such as 1 [W] (watt), 0.5 [W], 0.2 [W], 0.1 [W], 0.05 [W], 0.01 [W], and 0.001 [W], so that the user can select the "lower-than-normal transmission power" value they desire.

[0150] Alternatively, a variable resistor or the like may be used to make the value continuously variable, allowing the user to select a desired value of "transmission power lower than normal."

[0151] This section describes the upper limit of the transmission power set by this wireless transceiver, the current transmission power, the status display regarding the raw reception strength and the reduced reception sensitivity, and warning messages.

[0152] When the upper limit of the transmission power is changed and the reception sensitivity is changed in conjunction with the change, both or either of the set upper limit of the transmission power and the current transmission power may be displayed.

[0153] The signal strength at "normal reception sensitivity" and / or "lower than normal reception sensitivity" may be displayed.

[0154] If the upper limit of the transmission power is lowered and the reception sensitivity is lowered accordingly, the state may be displayed as "pseudo out of range" and the user may be notified by other expressions, lights, sounds, or voices. This allows the user to know whether communication is possible.

[0155] If the strength of the radio wave received from the "other party in the wireless transmission / reception" becomes weak during a call, the user may be notified by a display, lamp, sound, or voice.

[0156] In addition, when the transmission power is "lower than normal," this wireless transceiver may transmit information to the "other party in the wireless transmission / reception" to notify that the transmission power is "lower than normal."

[0157] The specific operation of the wireless transmitter / receiver of this embodiment will be explained using a commercially available general mobile phone as an example.

[0158] The last time you turned on your mobile phone, it was already set to "lower than normal transmission power" and at the same time, the receiver sensitivity was also set to "lower than normal reception sensitivity." At this time, the maximum transmission power was set to 0.1 [W] and the receiver sensitivity was set to -10 [dB]. The normal maximum transmission power is 1 [W] and the receiver sensitivity is 0 [dB].

[0159] My cell phone is currently at a campsite in a valley far from any base station. Even with the strongest base station, I can't communicate with it because the transmission power is 0.1 W and the reception sensitivity is -10 dB. Under normal conditions, with a transmission power of 1 W and a reception sensitivity of ±0 dB, I can still make a call.

[0160] Now, let's say that the mobile phone is turned off and the user turns it on. Normally, the mobile phone sends a control signal to a base station that can receive it, registers with that base station, and becomes ready for communication. However, the mobile phone's current settings are a maximum transmission output of 0.1 [W] and a receiving sensitivity of -10 [dB], so communication is not possible.

[0161] At this time, the display on the mobile phone will show the display in Figure 7. 978, which represents transmission power, indicates that the maximum transmission power is being limited. 974, which represents signal strength at normal reception sensitivity, indicates that the received signal is weak. 975, which represents signal strength at reduced reception sensitivity, indicates that reception is not possible. Since the user has set the transmission power to "lower than normal" and communication is not possible, 976, which represents a pseudo-out-of-range state, is highlighted.

[0162] Figure 8 shows a modified design of the icon in Figure 7. 988, which represents transmission power, indicates that the maximum transmission power is limited. 984, which represents signal strength at normal reception sensitivity, indicates that the received signal is weak. 985, which represents signal strength at reduced reception sensitivity, indicates that reception is not possible. Since the user has set "lower-than-normal transmission power" and is therefore unable to communicate, 986, which represents a pseudo-out-of-range state, is highlighted.

[0163] The user really wants to make a call, so he presses key switch 911 in Figure 10, which sets the transmission power and reception sensitivity to normal. The mobile phone's transmission output is 1 [W], and the reception sensitivity is at maximum normal. This allows the call to be made.

[0164] After the call is ended, if the key switch 912 in FIG. 10 is pressed to set the transmission power and reception sensitivity to a lower level than normal, the maximum transmission power will be 0.1 [W] and the reception sensitivity will be -10 [dB].

[0165] In this way, in this embodiment, the wireless transceiver lowers the upper limit of the transmission power by operating the "operation means" 114, and lowers the reference value for determining that communication has been established in accordance with the lowered upper limit of the transmission power.

[0166] This allows the user to determine the upper limit of the transmission power of the wireless transceiver, and by managing the transmission power, the power consumption can be reduced and continuous operation time can be extended. It also weakens the effect of radio frequency electromagnetic fields on the human body. Furthermore, it reduces the degree to which "communication symmetry" is broken.

[0167] In this embodiment, the "correction control signal" 352 input to the "communication establishment determination unit" 430 corresponds to the "reference value when determining that communication has been established" of invention 4.

[0168] [Third embodiment] A radio transceiver according to a third embodiment of the present invention will be described below. Fig. 3 is a diagram showing the basic configuration of the radio transceiver according to the third embodiment.

[0169] This wireless transceiver has the same effect as the wireless transceiver according to the second embodiment, but has a different configuration.

[0170] In the wireless transceiver according to the second embodiment, the “corrected control signal” 352 is simultaneously input to the “transmission power determination unit” 460 and the “communication establishment determination unit” 430, thereby controlling the transmission power and the reception sensitivity in conjunction with each other.

[0171] Furthermore, in order to determine whether good communication with the wireless base station can be expected, the value of the "received level signal" 335 and the value of the "corrected control signal" 352 are compared in the "communication establishment determination unit" 430.

[0172] Compared to the wireless transceiver according to the second embodiment, the wireless transceiver according to this embodiment is provided with a "sensitivity converter" 112 on the input side of "communication establishment determination unit" 440, and further includes a "reference value generator" 142 in addition to a "level comparator" 141 in "communication establishment determination unit" 440.

[0173] An example circuit of the "sensitivity converter" 112 is shown in Fig. 18. The "sensitivity converter" 112 can be configured as shown in Fig. 18(a). In the example of Fig. 18(a), the "sensitivity converter" 112 is configured with an "adder" 554 which is an analog circuit. The "adder" 554 receives the "receiving level signal" 335 and the "correction control signal" 352, adds the "receiving level signal" 335 and the "correction control signal" 352 together, and outputs the result of this addition, the "converted receiving level signal" 313, from an output terminal.

[0174] The "sensitivity converter" 112 can be configured as shown in Fig. 18(b). In the example of Fig. 18(b), the "sensitivity converter" 112 is configured to include a "D / A converter" 569 that receives the "correction control signal" 352 (digital signal) and performs D / A conversion, and an "adder" 554 that is an analog circuit. The "adder" 554 receives the "reception level signal" 335 and the D / A converted "correction control signal" 352, adds the "reception level signal" 335 and the "correction control signal" 352, and outputs the result of this addition, the "converted reception level signal" 313, from an output terminal.

[0175] The "sensitivity converter" 112 can be configured as shown in Fig. 18(c). In the example of Fig. 18(c), the "sensitivity converter" 112 is configured to include an "A / D converter" 568 that receives and A / D-converts the "reception level signal" 335, and an "adder" 556 that is a logic circuit. The "adder" 556 receives the A / D-converted "reception level signal" 335 and the "correction control signal" 352 (digital signal), adds the "reception level signal" 335 and the "correction control signal" 352, and outputs the result of this addition, the "converted reception level signal" 313 (digital signal), from an output terminal.

[0176] 19 and 20 show circuit examples of the "communication establishment determination unit" 440. The "communication establishment determination unit" 440 can be configured as shown in FIG. 19(a). In the example of FIG. 19(a), the "communication establishment determination unit" 440 is configured with a "level comparator" 141 and a "reference value generator" 142. The "level comparator" 141 is configured with a "comparator" 553, which is an analog circuit. The "comparator" 553 receives the "converted reception level signal" 313 from its non-inverting input terminal, receives the "reference voltage" 719 from its inverting input terminal, and outputs a "communication establishment determination signal" 343 from its output terminal. The "reference value generator" 142 is configured with a "first resistor element" having one end connected to the "power supply" VDD and the other end connected to the inverting input terminal of the "comparator" 553, and a "second resistor element" having one end connected to the inverting input terminal of the "comparator" 553 and the other end grounded.

[0177] The "communication establishment determination unit" 440 can be configured as shown in Fig. 19(b). In the example of Fig. 19(b), the "communication establishment determination unit" 440 is configured to include a "level comparator" 141 and a "reference value generator" 142. The "level comparator" 141 is the same as in Fig. 19(a). The "reference value generator" 142 is configured to include a "CPU" 545 that outputs a data signal (digital signal) equivalent to the "reference voltage" 719, and a "D / A converter" 569 that D / A converts the data signal from the "CPU" 545 and outputs it as the "reference voltage" 719.

[0178] The "communication establishment determination unit" 440 can be configured as shown in Fig. 19(c). In the example of Fig. 19(c), the "communication establishment determination unit" 440 is configured to have a "level comparator" 141 and a "reference value generator" 142. The "level comparator" 141 is the same as in Fig. 19(a). The "reference value generator" 142 is configured to have a "resistance element" having one end connected to a "power supply" VDD and the other end connected to the inverting input terminal of a "comparator" 553, and a "Zener diode" 565 having a cathode terminal connected to the inverting input terminal of the "comparator" 553 and an anode terminal grounded.

[0179] The "communication establishment determination unit" 440 can be configured as shown in FIG. 20(a). In the example of FIG. 20(a), the "communication establishment determination unit" 440 is configured to include a "level comparator" 141 and a "reference value generator" 142. The "level comparator" 141 is configured to include a weighted "comparator" 558 using a logic circuit. The "comparator" 558 receives "converted reception level signal" 313 (digital signal) from a first input terminal, receives "reference value" 718 from a second input terminal, and outputs "communication establishment determination signal" 343 from an output terminal. "Reference value generator" 142 has n+1 "resistance elements" having one end connected to "power supply" VDD, and n+1 "switch elements" having one end connected to the other end of each "resistance element" and the other end grounded, and the output signal from the other end of each "resistance element" corresponds to each bit of "reference value" 718 consisting of n+1 bits.

[0180] The "communication establishment determination unit" 440 can be configured as shown in FIG. 20(b). In the example of FIG. 20(b), the "communication establishment determination unit" 440 is configured to include a "level comparator" 141 and a "reference value generator" 142. The "level comparator" 141 is the same as in FIG. 20(a). The "reference value generator" 142 is configured to include a "first resistor element" having one end connected to a "power supply" VDD, a "second resistor element" having one end grounded, and an "A / D converter" 568 that A / D converts output signals from the other ends of the "first resistor element" and the "second resistor element" and outputs a "reference value" 718.

[0181] The "communication establishment determination unit" 440 can be configured as shown in FIG. 20(c). In the example of FIG. 20(c), the "communication establishment determination unit" 440 is configured to include a "level comparator" 141 and a "reference value generator" 142. The "level comparator" 141 is the same as in FIG. 20(a). The "reference value generator" 142 is configured to include a "resistance element" having one end connected to a "power supply" VDD, a "Zener diode" 565 having an anode terminal grounded, and an "A / D converter" 568 that A / D converts the output signal from the other end of the "resistance element" and the cathode terminal of the "Zener diode" 565, and outputs a "reference value" 718.

[0182] Furthermore, the "corrected control signal" 352 output from the "control signal generating unit" 450 is input to the "transmission power determining unit" 460 and at the same time to the "sensitivity converter" 112. This allows the transmission power and reception sensitivity to be controlled in conjunction with each other.

[0183] The "reception level signal" 335 output by the "receiving unit" 420 is input to the "sensitivity converter" 112. The value of the "reception level signal" 335 is converted at a conversion rate that changes depending on the value of the "correction control signal" 352, and is output as the "converted reception level signal" 313.

[0184] The "converted reception level signal" 313 is input to the "communication establishment determination unit" 440, where it is compared by the "level comparator" 141 with the value generated by the "reference value generator" 142, and the "communication establishment determination unit" 440 determines the state of the "communication establishment determination signal" 343.

[0185] The "communication establishment determination signal" 343 is output in either the "communication establishment possible" or "communication establishment not possible" state.

[0186] The value generated by the "reference value generator" 142 is determined and registered by a communications carrier, device manufacturer, or user. Alternatively, the wireless transceiver may calculate and register an optimal value. A combination of these may also be used.

[0187] As described above, the wireless transceiver according to this embodiment is a wireless transceiver that allows the user to change the upper limit of the transmission power of the wireless transceiver, and by changing the reception sensitivity in conjunction with this and referring to the “communication establishment determination signal” 343, it is possible to suppress problems that may occur as a result of lowering the maximum transmission power.

[0188] This allows the user to reduce power consumption by lowering the transmission power depending on the situation.

[0189] In this embodiment, the "correction control signal" 352 input to the "sensitivity converter" 112 corresponds to the "reference value when determining that communication is established" of the fourth aspect.

[0190] [Fourth embodiment] A wireless transceiver according to a fourth embodiment of the present invention will be described. The fourth embodiment corresponds to an example of the wireless transceiver according to inventions 11 to 15. Figure 4 is a diagram showing the basic configuration of the wireless transceiver according to the fourth embodiment.

[0191] This wireless transceiver is a wireless transceiver in which a "means for detecting and processing various events" 116 is added to the wireless transceiver according to the second embodiment.

[0192] The "means for detecting and processing various events" 116 changes the transmission power and reception sensitivity in conjunction with the situation intended by the user or the situation registered in advance.

[0193] The following is an example of a wireless transceiver according to invention 11. Only the additional parts will be described. This wireless transceiver is equipped with the following means, and is a wireless transceiver that allows the user to change the upper limit of the transmission power through operation, and by changing the reception sensitivity in conjunction with this, it is a wireless transceiver that can suppress problems that may occur when only the maximum transmission power is reduced.

[0194] An example of the wireless transceiver of invention 11 is a wireless transceiver according to the second embodiment, which is further equipped with an “operation means” 114, an “operation command processing section” 481, and a “control signal generating section” 480 capable of processing “request information” 391.

[0195] An example circuit of the "control signal generating unit" 480 is shown in Fig. 14. As shown in Fig. 14, the "control signal generating unit" 480 is configured to have a "CPU" 545 that performs calculations and control based on a control program, a "ROM" 547 that stores the control program and the like for the "CPU" 545 in advance in a predetermined area, a "RAM" 546 for storing data read from the "ROM" 547 and the like and calculation results required in the calculation process of the "CPU" 545, and a "D / A converter" 569 that D / A converts the data signal from the "CPU" 545 and outputs the "correction control signal" 352, and these are connected to each other so that they can send and receive data by a "CPU bus", which is a signal line for transferring data.

[0196] An "operation command processing unit" 481 is connected to the "CPU bus" via an I / F (not shown), and "request information" 391 from the "operation command processing unit" 481 is input to the "control signal generating unit" 480. The "operation command processing unit" 481 is connected to the "operation means" 114, and an "operation signal" 315 from the "operation means" 114 is input.

[0197] A "remote control command detection processing unit" 482 is connected to the "CPU bus" via an I / F (not shown), and "request information" 392 from the "remote control command detection processing unit" 482 is input to the "control signal generating unit" 480.

[0198] A "communication partner detection and comparison unit" 483 is connected to the "CPU bus" via an I / F (not shown), and "request information" 393 from the "communication partner detection and comparison unit" 483 is input to the "control signal generation unit" 480.

[0199] A "wired earphone, microphone detection unit" 484 is connected to the "CPU bus" via an I / F (not shown), and "request information" 394 from the "wired earphone, microphone detection unit" 484 is input to the "control signal generation unit" 480.

[0200] A "wireless earphone, microphone detection unit" 485 is connected to the "CPU bus" via an I / F (not shown), and "request information" 395 from the "wireless earphone, microphone detection unit" 485 is input to the "control signal generation unit" 480.

[0201] A "current position detection area comparison unit" 486 is connected to the "CPU bus" via an I / F (not shown), and "request information" 396 from the "current position detection area comparison unit" 486 is input to the "control signal generation unit" 480.

[0202] The "CPU bus" is connected to a "time information acquisition time zone comparison unit" 487 via an I / F (not shown), and "request information" 397 from the "time information acquisition time zone comparison unit" 487 is input to a "control signal generation unit" 480.

[0203] The "CPU bus" is connected to an "emergency alert transmission detection unit" 488 via an I / F (not shown), and "request information" 398 from the "emergency alert transmission detection unit" 488 is input to the "control signal generation unit" 480.

[0204] An "emergency alert reception detection unit" 489 is connected to the "CPU bus" via an I / F (not shown), and "request information" 399 from the "emergency alert reception detection unit" 489 is input to the "control signal generation unit" 480.

[0205] An "operation command processing section" 481 is provided on the input side of the "control signal generating section" 480. An "operation means" 114 is provided on the input side of the "operation command processing section" 481.

[0206] An "operation signal" 315 is input from the "operation means" 114 to the "operation command processing unit" 481. Request information 391 is input from the "operation command processing unit" 481 to the "control signal generating unit" 480.

[0207] The “operation means” 114 can be implemented as a changeover switch, a push button switch, a variable resistor, etc. When the user operates the “operation means” 114, it generates an “operation signal” 315 and outputs it to the “operation command processing unit” 481.

[0208] The 'operation command processing unit' 481 performs processing based on the 'operation signal' 315 output by the 'operation means' 114 , and outputs the result to the 'control signal generating unit' 480 as 'request information' 391 .

[0209] The 'control signal generator' 480 generates and outputs the 'correction control signal' 352 based on the 'request information' 391 .

[0210] This allows the user to change the upper limit of the transmission power and change the reception sensitivity accordingly, and also return the upper limit of the transmission power to its maximum.

[0211] Therefore, depending on the operation performed by the user, the transmission power can be switched to "transmission power lower than normal" or returned to "normal transmission power", and in conjunction with the switching of the transmission power, the reception sensitivity can also be switched to "reception sensitivity lower than normal" or returned to "normal reception sensitivity".

[0212] As an example, the operation of the "operation command processing unit" 481 and the "control signal generating unit" 480 when the user operates the "operation means" 114 on the main body to set the upper limit of the transmission power lower than normal is shown below.

[0213] When the user operates the “operation means” 114 of the main body, the “operation means” 114 outputs an “operation signal” 315 to the “operation command processing unit” 481 .

[0214] The 'operation command processing unit' 481 processes the input 'operation signal' 315 and outputs 'request information' 391 for changing the upper limit of the transmission power to the 'control signal generating unit' 480 .

[0215] The 'control signal generator' 480 outputs the 'correction control signal' 352 that changes the upper limit of the transmission power and the reception sensitivity according to the input 'request information' 391 .

[0216] The following is an example of a wireless transceiver according to invention 12. Only the additional parts will be explained. This wireless transceiver is equipped with the following means, and can be remotely controlled from an external device using a communication means to change the upper limit of the transmission power and, in conjunction with this, change the reception sensitivity.

[0217] An example of a wireless transceiver according to the twelfth aspect of the present invention is the wireless transceiver according to the second embodiment, which is equipped with a remote-operation command detection processing unit 482 and a control signal generating unit 480 capable of processing the request information 392. An example of the circuit of the control signal generating unit 480 is shown in FIG.

[0218] A "remote control command detection processing unit" 482 is provided on the input side of the "control signal generating unit" 480. A "demodulated signal" 332 is input from the "receiving unit" 420 to the "remote control command detection processing unit" 482.

[0219] The “request information” 392 is input from the “remote operation command detection processing unit” 482 to the “control signal generation unit” 480 .

[0220] The “remote control command detection processing unit” 482 detects remote control command information from information transmitted from the outside using communication means, and creates “request information” 392 from the result and outputs it to the “control signal generation unit” 480.

[0221] In addition, the "remote control command detection processing unit" 482 determines whether remote control is possible by comparing the identification information of the remote control source, such as the line number, IP address, URL, email address, MAC address, etc., with the "pre-registered remote control source identification information."

[0222] The "control signal generating unit" 480 determines the upper limit of the transmission power and the reception sensitivity based on the "request information" 392 output by the "remote operation command detection processing unit" 482. The output is a "correction control signal" 352 that changes the

[0223] The "pre-registered remote control source identification information" may be any desired information registered by a communications carrier, device manufacturer, or user. Alternatively, the wireless transceiver may generate and register the information. Alternatively, a combination of these may be used.

[0224] The "pre-registered remote control source identification information" may include a line number, IP address, URL, email address, MAC address, etc. that identifies a specific person in charge of management.

[0225] In this remote control, communication including operation command information in some form can be used, such as email including an operation command code, a voice call signal including an operation command tone, a voice call signal including an operation command pulse, or a call counting the number of operation commands.

[0226] Furthermore, by utilizing this remote control, it becomes possible to use one management wireless transceiver to operate and manage the transmission power status of multiple other wireless transceivers.

[0227] The following is an example of a wireless transceiver according to invention 13. Only the additional parts will be explained. This wireless transceiver is equipped with the following means, so that when transmitting to a pre-registered "partner in information transmission," the reduced upper limit of transmission power returns to normal.

[0228] An example of a wireless transceiver according to the thirteenth aspect of the present invention is a wireless transceiver according to the second embodiment, which is equipped with a communication partner detection / comparison unit 483 and a control signal generation unit 480 capable of processing request information 393. An example of the circuit of control signal generation unit 480 is shown in FIG.

[0229] A "communication partner detection / comparison unit" 483 is provided on the input side of the "control signal generation unit" 480. "Request information" 393 is input from the "communication partner detection / comparison unit" 483 to the "control signal generation unit" 480.

[0230] The “communication partner detection and comparison unit” 483 detects identification information such as the line number, IP address, URL, email address, MAC address, etc. of the “partner in information transmission” with which communication is about to begin, compares this identification information with “pre-registered important communication partner identification information,” and outputs “request information” 393 to the “control signal generation unit” 480 based on the results.

[0231] Based on the "request information" 393 output by the "communication partner detection / comparison unit" 483, the "control signal generation unit" 480 maximizes or increases the upper limit of the transmission power, and generates and outputs the "correction control signal" 352 that changes the receiving sensitivity in conjunction with this.

[0232] For example, if the transmission power is "lower than normal transmission power," when communication is initiated with the "partner in information transmission" registered in the "pre-registered important communication party identification information," the transmission power that was "lower than normal transmission power" can be returned to "normal transmission power." Also, with regard to reception sensitivity, the reception sensitivity that was "lower than normal reception sensitivity" will return to "normal reception sensitivity" in conjunction with the transmission power.

[0233] The "pre-registered important communication party identification information" may be registered by a communications carrier, a device manufacturer, or a user. Alternatively, the wireless transceiver may register a party that has called repeatedly. Alternatively, a combination of these may be used.

[0234] In addition, the content of the "pre-registered important communication partner identification information" may include line numbers, IP addresses, URLs, email addresses, MAC addresses, etc. that identify public agencies such as the police and fire departments, which generally have a high level of urgency, as well as family members, specific friends, workplaces, specific business partners, etc., which are considered to be of high importance to the user.

[0235] The following is an example of a wireless transceiver according to invention 14. Only the additional parts will be explained. When the wireless transceiver according to invention 14 receives a call from a "partner in information transmission" registered in the "pre-registered important communication party identification information," it returns the transmission power, which was "lower than normal transmission power," to "normal transmission power." Furthermore, the reception sensitivity, which was "lower than normal reception sensitivity," also returns to "normal reception sensitivity" in conjunction with the state of the transmission power.

[0236] The embodiment of the wireless transceiver of the fourteenth invention is implemented by the configuration provided in the embodiment of the wireless transceiver of the thirteenth invention.

[0237] The “communication partner detection / comparison unit” 483 detects identification information such as the line number, IP address, URL, email address, MAC address, etc. of the incoming “partner in information transmission,” compares this identification information with “pre-registered important communication partner identification information,” and outputs “request information” 393 to the “control signal generation unit” 480 based on the result.

[0238] Based on the "request information" 393 output by the "communication partner detection / comparison unit" 483, the "control signal generation unit" 480 maximizes or increases the upper limit of the transmission power, and generates and outputs the "correction control signal" 352 that changes the receiving sensitivity in conjunction with this.

[0239] For example, if the transmission power is "lower than normal transmission power," when a call is received from a "partner in information transmission" registered in the "pre-registered important communication party identification information," the transmission power that was "lower than normal transmission power" can be returned to "normal transmission power." Also, with regard to reception sensitivity, the reception sensitivity that was "lower than normal reception sensitivity" will return to "normal reception sensitivity" in conjunction with the transmission power.

[0240] In addition, when the transmission power is returned to "normal transmission power" during communication with the "partner in information transmission" registered in the "pre-registered important communication party identification information," when the communication ends, the timing of switching the transmission power back to "lower than normal transmission power" may be such that the transmission power is immediately switched to "lower than normal transmission power," or may be such that the transmission power is switched to "lower than normal transmission power" after a certain period of time has elapsed. In addition, the state of the receiving sensitivity at this time will also be switched in conjunction with the state of the transmission power.

[0241] The following is an example of a wireless transceiver according to invention 15. The example of the wireless transceiver according to invention 15 is implemented by providing the wireless transceiver according to the second embodiment with the following means, which detect and process specific events, thereby making it possible for the wireless transceiver to change the upper limit of transmission power and change reception sensitivity in conjunction with this.

[0242] The following is an explanation of the "wired earphone, microphone detection unit" 484. Only the added parts will be explained.

[0243] This wireless transceiver is provided with the following means, so that when a wired earphone or a wired microphone is connected, the reduced upper limit of the transmission power returns to normal.

[0244] This example of a wireless transceiver is the wireless transceiver according to the second embodiment, equipped with a "wired earphone / microphone detection unit" 484 and a "control signal generation unit" 480 capable of processing "request information" 394. An example of the circuit of "control signal generation unit" 480 is shown in FIG.

[0245] A 'wired earphone / microphone detection unit' 484 is provided on the input side of the 'control signal generation unit' 480.

[0246] The “request information” 394 is input from the “wired earphone, microphone detection unit” 484 to the “control signal generation unit” 480 .

[0247] The 'wired earphone / microphone detection unit' 484 detects that a wired earphone or a wired microphone has been connected to the main body, and outputs 'request information' 394 to the 'control signal generation unit' 480 .

[0248] The "control signal generator" 480 maximizes or increases the upper limit of the transmission power, and changes the reception sensitivity in conjunction with this.

[0249] In other words, the transmission power that was "lower than normal transmission power" is returned to "normal transmission power." Also, the reception sensitivity that was "lower than normal reception sensitivity" is returned to "normal reception sensitivity" in conjunction with the state of the transmission power.

[0250] The following is an explanation of the "wireless earphone, microphone detection unit" 485. Only the added parts will be explained.

[0251] This wireless transceiver is provided with the following means, so that when a wireless earphone or a wireless microphone is connected, the reduced upper limit of transmission power returns to normal.

[0252] This example of a wireless transceiver is the wireless transceiver according to the second embodiment, equipped with a "wireless earphone / microphone detection unit" 485 and a "control signal generation unit" 480 capable of processing "request information" 395. An example of the circuit of "control signal generation unit" 480 is as shown in FIG.

[0253] A 'wireless earphone / microphone detection unit' 485 is provided on the input side of the 'control signal generation unit' 480.

[0254] “Request information” 395 is input from “wireless earphone, microphone detection unit” 485 to “control signal generation unit” 480 .

[0255] The 'wireless earphone / microphone detection unit' 485 detects that a wireless earphone or a wireless microphone has been connected to the main body, and outputs 'request information' 395 to the 'control signal generation unit' 480.

[0256] The "control signal generator" 480 maximizes or increases the upper limit of the transmission power, and changes the reception sensitivity in conjunction with this.

[0257] In other words, the transmission power that was "lower than normal transmission power" is returned to "normal transmission power." Also, the reception sensitivity that was "lower than normal reception sensitivity" is returned to "normal reception sensitivity" in conjunction with the state of the transmission power.

[0258] The following is an explanation of the "current position detection area comparison unit" 486. Only the added parts will be explained.

[0259] This wireless transceiver is provided with the following means, so that when the wireless transceiver is in a pre-registered area, the reduced upper limit of transmission power is returned to normal.

[0260] This example of a wireless transceiver is the wireless transceiver according to the second embodiment, further comprising a "current location detection area comparison unit" 486 and a "control signal generation unit" 480 capable of processing "request information" 396. An example of the circuit of "control signal generation unit" 480 is shown in FIG.

[0261] A "current position detection area comparison unit" 486 is provided on the input side of the "control signal generation unit" 480. "Request information" 396 is input from the "current position detection area comparison unit" 486 to the "control signal generation unit" 480.

[0262] The 'current position detection area comparison unit' 486 detects the current position information, compares it with the 'pre-registered area information', and outputs the 'request information' 396 to the 'control signal generation unit' 480 .

[0263] The "control signal generator" 480 maximizes or increases the upper limit of the transmission power, and changes the reception sensitivity in conjunction with this.

[0264] In other words, the transmission power that was "lower than normal transmission power" is returned to "normal transmission power." Also, the reception sensitivity that was "lower than normal reception sensitivity" is returned to "normal reception sensitivity" in conjunction with the state of the transmission power.

[0265] The "pre-registered area information" is area information desired by a communications carrier, a device manufacturer, or a user. Alternatively, the wireless transceiver may generate and register the area information. A combination of these methods may also be used.

[0266] The content of the "pre-registered area information" may include the site of a medical facility.

[0267] The following is an explanation of the "time information acquisition time zone comparison unit" 487. Only the added parts will be explained.

[0268] This wireless transceiver is provided with the following means, so that the reduced upper limit of transmission power is returned to normal during a pre-registered time period.

[0269] This example of a wireless transceiver is the wireless transceiver according to the second embodiment, equipped with a "time information acquisition time zone comparison unit" 487 and a "control signal generation unit" 480 capable of processing "request information" 397. An example of the circuit of "control signal generation unit" 480 is as shown in FIG.

[0270] A "time information acquisition time period comparison unit" 487 is provided on the input side of the "control signal generation unit" 480. "Request information" 397 is input from the "time information acquisition time period comparison unit" 487 to the "control signal generation unit" 480.

[0271] The 'time information acquisition time zone comparison unit' 487 acquires the current time information, compares it with the 'pre-registered time zone information', and outputs 'request information' 397 to the 'control signal generation unit' 480 .

[0272] The "control signal generator" 480 controls the transmission power. The receiver sensitivity is changed accordingly.

[0273] In other words, the transmission power that was "lower than normal transmission power" is returned to "normal transmission power." Also, the reception sensitivity that was "lower than normal reception sensitivity" is returned to "normal reception sensitivity" in conjunction with the state of the transmission power.

[0274] The "pre-registered time zone information" is registered by a communication carrier, a device manufacturer, or a user as desired. Alternatively, the wireless transceiver may generate and register the time zone information. Alternatively, a combination of these methods may be used.

[0275] The "pre-registered time zone information" may include commuting time zones, school commuting time zones, and time zones for going to cram schools.

[0276] The following is a description of the "emergency alert transmission detection unit" 488. Only the added parts will be described.

[0277] This wireless transceiver is provided with the following means, so that when the emergency alert transmission function is used, the reduced upper limit of transmission power is returned to normal.

[0278] This example of a wireless transceiver is the wireless transceiver according to the second embodiment, further comprising an "emergency alert transmission detection unit" 488 and a "control signal generation unit" 480 capable of processing "request information" 398. An example of the circuit of "control signal generation unit" 480 is shown in FIG. 14.

[0279] An "emergency alert transmission detection unit" 488 is provided on the input side of the "control signal generation unit" 480. "Request information" 398 is input from the "emergency alert transmission detection unit" 488 to the "control signal generation unit" 480.

[0280] An 'emergency alert transmission detection unit' 488 detects information output from the emergency alert transmission function, and outputs 'request information' 398 to a 'control signal generation unit' 480 .

[0281] The "control signal generator" 480 maximizes or increases the upper limit of the transmission power, and changes the reception sensitivity in conjunction with this.

[0282] In other words, the transmission power that was "lower than normal transmission power" is returned to "normal transmission power." Also, the reception sensitivity that was "lower than normal reception sensitivity" is returned to "normal reception sensitivity" in conjunction with the state of the transmission power.

[0283] The emergency alert transmission function is provided in the main body of this radio transceiver, and in the event of an emergency such as a fire or imminent danger, it is possible to instantly and easily send an emergency alert to the emergency alert destination without having to enter a line number.

[0284] The emergency alert destinations may include public institutions such as the police and fire department, security companies, school officials, neighborhood association officials, and parents.

[0285] The following is a description of the "emergency alert reception detection unit" 489. Only the added parts will be described.

[0286] This wireless transceiver is provided with the following means, so that when an emergency alert signal is received, the reduced upper limit of transmission power is returned to normal.

[0287] This example of a wireless transceiver is the wireless transceiver according to the second embodiment, equipped with an "emergency alert reception detection unit" 489 and a "control signal generation unit" 480 capable of processing "request information" 399. An example of the circuit of "control signal generation unit" 480 is as shown in FIG. 14.

[0288] An "emergency alert reception detector" 489 is provided on the input side of the "control signal generator" 480. A "demodulated signal" 332 is input from the "receiver" 420 to the "emergency alert reception detector" 489.

[0289] The “request information” 399 is input from the “emergency alert reception detector” 489 to the “control signal generator” 480 .

[0290] The 'emergency alert reception detector' 489 detects the received emergency alert signal and outputs 'request information' 399 to the 'control signal generator' 480 .

[0291] The "control signal generator" 480 maximizes or increases the upper limit of the transmission power, and changes the reception sensitivity in conjunction with this.

[0292] In other words, the transmission power that was "lower than normal transmission power" is returned to "normal transmission power." Also, the reception sensitivity that was "lower than normal reception sensitivity" is returned to "normal reception sensitivity" in conjunction with the state of the transmission power.

[0293] The emergency alert signal is a radio signal transmitted when the emergency alert transmission function is activated, or may be a radio signal transmitted based on earthquake information or tsunami information issued by a government agency.

[0294] In this embodiment, the "correction control signal" 352 input to the "communication establishment determination unit" 430 corresponds to the "reference value when determining that communication has been established" of invention 4.

[0295] [Fifth embodiment] A radio transceiver according to a fifth embodiment of the present invention will be described below. Fig. 5 is a diagram showing the basic configuration of the radio transceiver according to the fifth embodiment.

[0296] This wireless transmitter / receiver detects its current location, and if it is in a pre-registered area, it lowers the upper limit of the transmission power and, in conjunction with that, lowers the reception sensitivity. In other words, it lowers both the transmission power and the reception sensitivity at the same time.

[0297] The wireless transceiver according to this embodiment is the wireless transceiver according to the second embodiment, further comprising a "current location detection area comparison unit" 486 and a "control signal generation unit" 480 capable of processing "request information" 396. An example of the circuit of "control signal generation unit" 480 is as shown in FIG.

[0298] A "current position detection area comparison unit" 486 is provided on the input side of the "control signal generation unit" 480. "Request information" 396 is input from the "current position detection area comparison unit" 486 to the "control signal generation unit" 480.

[0299] The “current location detection area comparison unit” 486 detects the current location of this wireless transceiver, determines whether the location is inside or outside the area indicated by the “pre-registered area information,” and then determines whether the transmission power state should be switched, and outputs the result to the “control signal generation unit” 480 as “request information” 396.

[0300] The "control signal generating unit" 480 generates and outputs the "corrected control signal" 352 based on the "request information" 396. The "corrected control signal" 352 is output to the "transmission power determining unit" 460 and is also output to the "communication establishment determining unit" 430.

[0301] That is, the "transmission power determination unit" 460 and the "communication establishment determination unit" 430 are controlled by a single operation.

[0302] Therefore, depending on the location of this wireless transceiver, the transmission power can be switched to "lower than normal transmission power" or returned to "normal transmission power," and in conjunction with the switching of the transmission power, the reception sensitivity can also be switched to "lower than normal reception sensitivity" or returned to "normal reception sensitivity."

[0303] In this embodiment, the "correction control signal" 352 input to the "communication establishment determination unit" 430 corresponds to the "reference value when determining that communication has been established" of invention 4.

[0304] [Variations] An example will be described in which the wireless transceiver according to the first to fifth embodiments is applied as a wireless terminal in a mobile communication system, and area information of a hospital site is registered in the "pre-registered area information".

[0305] If a picocell is installed within a hospital ward, it is possible to reduce the transmission power of wireless terminals with which the picocell is the "partner in wireless transmission and reception." However, if, for example, the wireless terminal is near a window and the radio waves received from a wireless base station outside the hospital grounds are stronger, the wireless terminal may communicate at a high transmission power in response to the radio waves received from that wireless base station, and as a result, there is a risk that the transmission power will not be reduced.

[0306] Even in such a case, by registering the area information of the hospital grounds in the "pre-registered area information" as in the case of the wireless transceiver according to the fourth embodiment described above, it is possible to reliably suppress the transmission output within the hospital grounds.

[0307] The picocell plays the role of a radio base station in a mobile communication system, but is a small radio base station for indoor installation that has low transmission power and ensures radio transmission and reception in a very narrow and limited area.

[0308] The radio transmitter / receiver according to the first to fifth embodiments is merely an example, which can suppress adverse effects that may occur due to a change in transmission power by simultaneously making some change to the "reception system" when the user changes the transmission power, thereby preventing confusion for the user.

[0309] Furthermore, although the wireless transmitter / receivers according to the first to fifth embodiments have been described as examples of application to wireless terminal devices in mobile communication systems, the present invention can also be implemented in one-to-one communication relationships such as transceivers.

[0310] Furthermore, in the wireless transceivers according to the second to fifth embodiments, the strength of the received radio waves is measured, the transmission power is controlled based on this, and a state in which good communication can be expected is determined. However, in digital communication, instead of measuring the strength of the received radio waves, the error rate of the received data may be measured, and the receiving sensitivity may be controlled based on this error rate, and a state in which good communication can be expected may be determined.

[0311] Furthermore, in the first embodiment and its modified example, the receiver sensitivity is reduced in accordance with the upper limit of the transmission power reduced by the operation of the "operation means" 114. However, the present invention is not limited to this, and in digital communications, the allowable error rate of the received data can also be reduced in accordance with the upper limit of the transmission power reduced by the operation of the "operation means" 114. Specifically, in the "normal transmission power" state, it is determined that communication is established when the error rate of the received data is equal to or lower than a first threshold value (allowable error rate), whereas in the "lower-than-normal transmission power" state, it is determined that communication is established when the error rate of the received data is equal to or lower than a second threshold value (allowable error rate) that is lower than the first threshold value.

[0312] Furthermore, in the first to fifth embodiments and their modifications, in addition to a configuration in which transmission control and reception control are performed by a single operation, it is also possible to adopt (1) a configuration in which transmission control and reception control are performed by multiple operations, (2) a configuration in which transmission control is performed by a first operation (one or more operations) and then reception control is performed by a second operation (one or more operations), (3) a configuration in which reception control is performed by a first operation (one or more operations) and then transmission control is performed by a second operation (one or more operations), or (4) a configuration in which only transmission control is performed by a predetermined operation (one or more operations) and reception control is performed so that the reception range matches the transmission range or the mismatch between the transmission range and the transmission range is reduced regardless of the operation. Furthermore, the predetermined operation that triggers transmission control or reception control may be the same as an operation that activates another function. For example, if the predetermined operation is the same as an operation that increases or decreases the call volume, the upper limit of transmission power can be lowered in response to an operation that decreases the call volume.

[0313] Furthermore, in the first to fifth embodiments and their modifications, the receiving performance (e.g., receiving sensitivity, a reference value for determining whether communication is established, or a tolerance for the error rate of received data) is reduced in accordance with the upper limit of transmission power reduced by the operation of the "operation means" 114. However, this is not limiting. In a configuration in which the receiving status of the wireless transceiver is notified to the wireless base station and, for example, the wireless base station controls the transmission power, etc., based on the receiving status of the wireless transceiver, the receiving performance can be notified to the other party of the communication when the receiving performance is reduced or assumed to be reduced in accordance with the upper limit of transmission power reduced by the operation of the "operation means" 114. In this case, the receiving performance of the wireless transceiver may or may not be reduced as in the first to fifth embodiments. When the wireless transceiver actually reduces the receiving performance, the notification content is the receiving performance when the receiving performance is reduced in accordance with the reduced upper limit of transmission power. When the wireless transceiver does not reduce the receiving performance but makes it appear as if it has been reduced to the wireless base station, the notification content is the receiving performance when the receiving performance is reduced in accordance with the reduced upper limit of transmission power. In analog communication, the reception status will be, for example, "The current reception strength is ** [dB]." In digital communication, it will be, for example, "The current error rate is **." However, the transmitted signal will contain the information "**." It is sufficient to include only the information.

[0314] In the first embodiment and its modifications, only the upper limit value of the transmission power among the transmission power characteristics is reduced as shown in Figures 22(a) and 22(d), but this is not limiting, and for example, the entire transmission power characteristics may be reduced. The same applies to the second to fifth embodiments and their modifications.

[0315] In the first embodiment and its modifications, the receiver sensitivity is reduced to a constant value 813 regardless of the propagation loss, as shown in Figures 22(b) and 22(e), but the present invention is not limited to this. For example, the receiver sensitivity may be reduced in stages from maximum receiver sensitivity 805 to a constant value 813 as the propagation loss increases. The same applies to the second to fifth embodiments and their modifications.

[0316] Furthermore, in the first embodiment and its modifications, the wireless transceiver is configured to lower the upper limit of transmission power by operating "operation means" 114 and to lower the reception sensitivity in accordance with the lowered upper limit of transmission power, but in Fig. 22, if "operation means" 114 is operated when the current transmission power is maximum transmission power 804, it can be said that the configuration sets a value (constant value 811) lower than the transmission power required for communication with the wireless base station (maximum transmission power 804) as the upper limit and suppresses the transmission power. The same applies to the second to fifth embodiments and their modifications. [Explanation of symbols]

[0317] 111 Antenna 112 Sensitivity converter 114 Operation means 116 Means for detecting and processing various events 121 Bandwidth limiter 122 Sensitivity controller 123 Automatic gain control amplifier 124 Automatic gain control amplifier A 125 Automatic gain control amplifier B 126 Channel selector 128 Demodulator 129 Reception level generator 141 Level comparator 142 Reference value generator 161 Level limiter 163 Level calculator 171 Carrier wave generator 172 Modulator 173 Transmission power controller 313 Converted reception level signal 315 Operation signal 331 Reception signal 332 Demodulation signal 335 Reception level signal 337 Signal strength information A 338 Signal strength information B 339 Signal error rate information 343 Communication establishment determination signal 352 Correction control signal 362 Transmission power control signal 374 Modulation signal 375 Transmission signals 391 to 399 Request information 410, 420 receiving unit 430, 440 communication establishment determination unit 450, 480 control signal generation unit 460 transmission power determination unit 470 transmission unit 481 operation command processing unit 482 remote operation command detection processing unit 483 communication partner detection comparison unit 484 wired earphone, microphone detection unit 485 wireless earphone,Microphone detection unit 486, current location detection area comparison unit 487, time information acquisition time zone comparison unit 488, emergency alert transmission detection unit 489, emergency alert reception detection unit 533, analog circuit inverting amplifier 545, CPU 546, RAM 547, ROM 551, voltage follower amplifier 553, analog circuit comparator 554, analog circuit adder 555, analog circuit subtractor 556, logic circuit adder 557, logic circuit subtractor 558, logic circuit weighted comparator 559, analog circuit level limiter 564, PIN diode 565, Zener diode 566, power amplifier 567, variable gain power amplifier 568, A / D converter 569, D / A converter 576, three-state buffer 577, flip-flop 578, analog switch 579, key switch 717, level limit reference voltage 718, reference value 719, reference voltage 800, transmission power 801 Receiving sensitivity 802, receiving strength 803, propagation loss 804 between a conventional wireless terminal (or a wireless transceiver according to the first embodiment) and a wireless base station, maximum transmission power 805 that can be exerted by a wireless transceiver (or a conventional wireless terminal), maximum receiving sensitivity 806 that can be exerted by a wireless transceiver (or a conventional wireless terminal), tolerances 807, 812, ranges 808, 814 in which a wireless transceiver (or a conventional wireless terminal) can transmit a signal to a wireless base station, range 809 in which a wireless transceiver (or a conventional wireless terminal) can receive a signal from a wireless base station, range 810 in which a conventional wireless terminal cannot transmit a signal to a wireless base station, ranges 811, 813 in which a conventional wireless terminal cannot receive a signal from a wireless base station,816 Constant value 815 Maximum reception strength 911 Key switch 912 for setting transmission power and reception sensitivity to normal state. Key switch 961 for setting transmission power and reception sensitivity to lower state than normal. User operates to lower transmission power 962 Transmission power decreases 963 Reception sensitivity decreases 964 Determine whether good communication can be expected 965 Expected 966 Communication possible 967 Not expected 968 Communication inhibited (out of range) 971 Display 972 The shaded area indicates the set upper limit of transmission power 973 The black area indicates the current transmission power 974 Represents signal strength at normal reception sensitivity 975 Represents signal strength at reduced reception sensitivity 976 Represents pseudo out of range, highlighted 977 Represents out of range 978 Represents transmission power 981 Display 982 The shaded area indicates the set upper limit of transmission power 983 The black area indicates the current transmission power 984 The left side shows the signal strength with normal receiving sensitivity 985, and the right side shows the signal strength with reduced receiving sensitivity 986. This shows the pseudo out-of-range state and is highlighted 987. 988 shows out-of-range state 991. 992. 993. 994. 995. 996. 997. 998. 9 ...

Claims

1. A radio transceiver comprising: means for lowering an upper limit of transmission power by a predetermined operation; and means for lowering reception performance in accordance with the upper limit of transmission power lowered by said predetermined operation.

2. 2. The wireless transceiver according to claim 1, wherein the reception performance is reception sensitivity.

3. 2. The wireless transceiver according to claim 1, wherein the reception performance is a reference value for determining whether communication has been established.

4. 2. The wireless transceiver according to claim 1, wherein the reception performance is a tolerance for an error rate of received data.

5. A radio transceiver comprising: means for lowering an upper limit of transmission power by a predetermined operation; and means for notifying a communication partner of a reception status when reception performance is lowered or when the reception performance is assumed to be lowered in accordance with the upper limit of transmission power lowered by said predetermined operation.

6. 6. The radio transceiver according to claim 5, wherein the reception performance is reception sensitivity.

7. 6. The wireless transceiver according to claim 5, wherein the reception performance is a reference value for determining whether communication has been established.

8. 6. The wireless transceiver according to claim 5, wherein the reception performance is a tolerance for an error rate of received data.

9. 7. The wireless transmitter / receiver according to claim 2, wherein the lowered reception sensitivity establishes communication with a partner in wireless transmission / reception with a radio wave intensity stronger than a pre-registered radio wave intensity.

10. 10. The wireless transceiver according to claim 9, wherein the upper limit of transmission power and reception sensitivity can be simultaneously lowered or restored to normal by a control signal generated by the user's predetermined operation.

11. A wireless transceiver having a transmission power control means and a reception sensitivity control means, the transmission power control means and the reception sensitivity control means being controlled by a predetermined operation, the wireless transceiver establishing communication with a partner in wireless transmission and reception at a radio wave intensity stronger than a pre-registered value by the controlled reception sensitivity, characterized in that the upper limit of the transmission power and the reception sensitivity can be simultaneously lowered or returned to normal by a control signal generated by transmitting information from outside and remotely operating the wireless transceiver.

12. A radio transmitter / receiver having a transmission power control means and a reception sensitivity control means, the transmission power control means and the reception sensitivity control means being controlled by a predetermined operation, the radio transmitter / receiver establishing communication with a partner in radio transmission / reception with a radio wave intensity stronger than a pre-registered value by the controlled reception sensitivity, characterized in that when transmitting to the partner in information transmission, with the upper limit value of the transmission power and the reception sensitivity lowered, the lowered upper limit value of the transmission power returns to normal.

13. A radio transmitter / receiver having a transmission power control means and a reception sensitivity control means, the transmission power control means and the reception sensitivity control means being controlled by a predetermined operation, the radio transmitter / receiver establishing communication with a party in radio transmission / reception having a stronger radio wave intensity than a pre-registered radio wave intensity by the controlled reception sensitivity, characterized in that when an incoming call is received from the pre-registered party in information transmission while the upper limit value of the transmission power and the reception sensitivity are lowered, the lowered upper limit value of the transmission power returns to normal.

14. A wireless transceiver having a transmission power control means and a reception sensitivity control means, the transmission power control means and the reception sensitivity control means being controlled by a predetermined operation, the wireless transceiver establishing communication with a partner in wireless transmission and reception at a radio wave intensity stronger than a pre-registered value by the controlled reception sensitivity, characterized in that when the upper limit of the transmission power and the reception sensitivity are lowered and connection of earphones is detected, the lowered upper limit of the transmission power returns to normal.

15. A wireless transceiver having a transmission power control means and a reception sensitivity control means, the transmission power control means and the reception sensitivity control means being controlled by a predetermined operation, the wireless transceiver establishing communication with a partner in wireless transmission and reception at a radio wave intensity stronger than a pre-registered value by the controlled reception sensitivity, characterized in that when the upper limit of the transmission power and the reception sensitivity are lowered and connection of a microphone is detected, the lowered upper limit of the transmission power returns to normal.

16. A radio transmitter / receiver having a transmission power control means and a reception sensitivity control means, the transmission power control means and the reception sensitivity control means being controlled by a predetermined operation, the radio transmitter / receiver establishing communication with a partner in radio transmission / reception at a radio field strength stronger than a pre-registered value by the controlled reception sensitivity, characterized in that when the radio transmitter / receiver is in a pre-registered position, the upper limit of the transmission power and the reception sensitivity can be simultaneously lowered or returned to normal.

17. A radio transmitter / receiver having a transmission power control means and a reception sensitivity control means, the transmission power control means and the reception sensitivity control means being controlled by a predetermined operation, the radio transmitter / receiver establishing communication with a partner in radio transmission / reception at a radio field strength stronger than a pre-registered value by the controlled reception sensitivity, and characterized in that at a pre-registered time, the upper limit value of the transmission power and the reception sensitivity can be simultaneously lowered or returned to normal.

18. A wireless transceiver having a transmission power control means and a reception sensitivity control means, wherein the transmission power control means and the reception sensitivity control means have a common control signal, and the wireless transceiver can simultaneously lower the upper limit of the transmission power and the reception sensitivity or return them to normal by manipulating the control signal, and the lowered reception sensitivity establishes communication with a partner in wireless transmission and reception where the radio wave strength is stronger than a pre-registered radio wave strength, characterized in that the wireless transceiver can lower the upper limit of the transmission power or return them to normal when the wireless transceiver is in a pre-registered area.

19. 9. The wireless transmitter / receiver according to claim 1, wherein, when reception performance is deteriorated, communication is established with a partner in wireless transmission / reception at a radio wave intensity stronger than a pre-registered radio wave intensity.

20. 20. The wireless transceiver according to claim 1, wherein the upper limit of transmission power and reception performance can be simultaneously reduced or restored to normal by a control signal generated by the predetermined operation of the user.

21. Claim In any one of items 1 to 8 and 19, a wireless transceiver characterized in that the upper limit value of transmission power and reception performance can be simultaneously reduced or restored to normal by a control signal generated by transmitting information from the outside and remotely operating the device.

22. 20. The wireless transceiver according to claim 1, wherein, when transmitting to a previously registered other party in information transmission in a state in which the upper limit value of transmission power and reception performance are reduced, the reduced upper limit value of transmission power is returned to normal.

23. 20. The wireless transceiver according to claim 1, wherein, in a state in which the upper limit value of transmission power and reception performance are reduced, when a call arrives from a previously registered other party in information transmission, the reduced upper limit value of transmission power is restored to normal.

24. 20. The wireless transceiver according to claim 1, wherein, in a state in which the upper limit value of transmission power and reception performance are reduced, when connection of an earphone is detected, the reduced upper limit value of transmission power returns to normal.

25. 20. The wireless transceiver according to claim 1, wherein, in a state in which the upper limit value of transmission power and reception performance are reduced, when connection of a microphone is detected, the reduced upper limit value of transmission power is returned to normal.

26. 20. The wireless transceiver according to claim 1, wherein when the wireless transceiver is in a pre-registered position, the upper limit of transmission power and reception performance can be simultaneously reduced or restored to normal.

27. 20. The wireless transceiver according to claim 1, wherein the upper limit of transmission power and reception performance can be simultaneously reduced or restored to normal at a pre-registered time.

28. A wireless transceiver having a transmission power control means and a reception performance control means, wherein the transmission power control means and the reception performance control means have a common control signal, and the wireless transceiver can simultaneously lower the upper limit of the transmission power and the reception performance or return them to normal by manipulating the control signal, and the lowered reception performance establishes communication with a partner in wireless transmission and reception where the radio wave strength is stronger than a pre-registered radio wave strength, characterized in that the wireless transceiver can lower the upper limit of the transmission power or return them to normal when the wireless transceiver is in a pre-registered area.

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