Method for switching wireless devices and wireless modules

Abstract

This disclosure aims to prevent degradation of radio wave intensity in a wireless device that shares an antenna with multiple wireless modules operating at different frequencies, without complicating or increasing the size of the configuration. [Solution] Each of the multiple wireless units includes a wireless module, an open circuit whose impedance is infinite to signals in the frequency band used by other wireless units, and an RF switch that electrically connects to a shared antenna in a way that allows switching between the wireless module and the open circuit. When a signal is transmitted from the shared antenna 1, the control unit 30 controls the RF switch so that the wireless unit whose frequency band is the frequency band of the signal transmitted from the shared antenna 1 is connected to the wireless module, and controls the RF switch so that the wireless unit whose frequency band is not the frequency band of the signal transmitted from the shared antenna 1 is connected to an open circuit.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a wireless device in which a single antenna is shared by a plurality of wireless modules.

BACKGROUND ART

[0002] Conventionally, there exists a wireless device in which an antenna is shared by a plurality of wireless modules using different operating frequencies. For example, an antenna may be shared between a 920 MHz specific low-power wireless module and an 800 MHz / 2 GHz LTE (Long Term Evolution) wireless module.

[0003] Such a wireless device has a problem that reception sensitivity or transmission power is degraded due to signals leaking to unintended wireless modules.

[0004] To address this problem, Patent Document 1 discloses a configuration in which a received signal received via a shared antenna is distributed to a corresponding receiver using a diplexer and a switch.

PRIOR ART DOCUMENTS

PATENT DOCUMENTS

[0005]

PATENT DOCUMENT 1

SUMMARY OF THE INVENTION

PROBLEMS TO BE SOLVED BY THE INVENTION

[0006] However, the configuration disclosed in Patent Document 1 has a problem that the device becomes complicated and large-sized due to the large circuit size of the diplexer.

[0007] The present disclosure has been made to solve the above problems, and an object of the present disclosure is to prevent degradation of radio field intensity with a simple configuration in a wireless device in which an antenna is shared by a plurality of wireless modules using different operating frequencies. [Means for solving the problem]

[0008] One wireless device of the present disclosure comprises a shared antenna, a plurality of radio units connected in parallel to the shared antenna and each assigned a different frequency band as its operating frequency, and a control unit that controls each of the plurality of radio units, each of the plurality of radio units comprising a radio module that transmits and receives signals of the operating frequency assigned to it, an open circuit whose impedance is infinite to signals of the operating frequency band of other radio units, and an RF switch that electrically connects to the shared antenna in a switchable manner between the radio module and the open circuit, wherein when a signal is transmitted from the shared antenna, the control unit controls the RF switch so that the shared antenna is connected to the radio module in the radio unit whose operating frequency is the frequency band of the signal transmitted from the shared antenna, and controls the RF switch so that the shared antenna is connected to the open circuit in the radio unit whose operating frequency is not the frequency band of the signal transmitted from the shared antenna.

[0009] Another wireless device of the present disclosure comprises a shared antenna, a plurality of radio units connected in parallel to the shared antenna and each assigned a different frequency band as its operating frequency, and a control unit that controls each of the plurality of radio units, each of the plurality of radio units comprising a radio module that transmits and receives signals on the operating frequency assigned to it, an open circuit whose impedance is infinite to signals on the operating frequency band of other radio units, and an RF switch that electrically connects to the shared antenna in a switchable manner between the radio module and the open circuit, wherein when transmitting a signal from the radio module of any of the plurality of radio units, the control unit controls the RF switch in the radio unit of the radio module that transmits the signal to connect to the radio module, and controls the RF switch in the radio unit that does not transmit a signal to connect to the open circuit. [Effects of the Invention]

[0010] According to the wireless device of the present disclosure, the wireless module electrically connected to the shared antenna is switched by the RF switch in accordance with the frequency band of the signal to be transmitted and received, so that it is possible to suppress the leakage of the transmitted and received signal to an unintended wireless module with a simple configuration, and prevent the deterioration of transmission and reception strength. Brief Description of Drawings

[0011] [Figure 1] FIG. 1 is a block diagram showing a configuration of the wireless device according to the first embodiment. [Figure 2] FIG. 2 is a diagram illustrating a state when the wireless device according to the first embodiment receives a signal of the second frequency band. [Figure 3] FIG. 3 is a flowchart illustrating an operation of the wireless device according to the first embodiment. [Figure 4] FIG. 4 is a block diagram showing a configuration of a wireless device according to a second embodiment. [Figure 5] FIG. 5 is a diagram illustrating a state when the wireless device according to the second embodiment receives a signal of the second frequency band. [Figure 6] FIG. 6 is a block diagram showing a configuration of a wireless device according to a third embodiment. [Figure 7] FIG. 7 is a diagram illustrating a state when the wireless device according to the third embodiment receives a signal of the second frequency band. [Figure 8] FIG. 8 is a diagram illustrating a state when the wireless device according to the third embodiment receives a signal of the third frequency band. Modes for Carrying Out the Invention

[0012] <A. Embodiment 1> <A-1. Configuration> FIG. 1 is a block diagram showing a configuration of the wireless device 101 according to the first embodiment. The wireless device 101 includes a shared antenna 1, a first wireless unit 21, a second wireless unit 22, and a control unit 30.

[0013] A high-frequency line is connected to the shared antenna 1. In other words, one end of the high-frequency line is connected to the shared antenna 1. The other end of the high-frequency line is branched into two, with the first wireless unit 21 connected to the first branch destination, and the second wireless unit 22 connected to the second branch destination respectively. In other words, the first wireless unit 21 and the second wireless unit 22 are connected in parallel to the shared antenna 1.

[0014] The first wireless unit 21 includes a first SPDT (Single-Pole Double-Throw) switch 2, a first wireless module 3, and a first open circuit 4. The SPDT switch has one input terminal and two output terminals, and is capable of switching the connection destination of the input terminal to either of the two output terminals.

[0015] The input terminal of the first SPDT switch 2 is connected to the shared antenna 1. The first output terminal of the first SPDT switch is connected to the first wireless module 3, and the second output terminal is connected to the first open circuit 4. The first wireless module 3 is a wireless module that uses the first frequency band as its operating frequency. The first open circuit 4 is a circuit whose impedance becomes infinite with respect to the second frequency band used by the second wireless module 6 described later.

[0016] The second wireless unit 22 includes a second SPDT switch 5, a second wireless module 6, and a second open circuit 7. The input terminal of the second SPDT switch 5 is connected to the shared antenna 1. The first output terminal of the second SPDT switch 5 is connected to the second wireless module 6, and the other output terminal is connected to the second open circuit 7. The second wireless module 6 is a wireless module that uses the second frequency band as its operating frequency. The second open circuit 7 is a circuit whose impedance becomes infinite with respect to the first frequency band.

[0017] In this way, the wireless device 101 is configured such that the first wireless module 3 and the second wireless module 6, which have different operating frequencies, share the same antenna.

[0018] The first wireless module 3 and the second wireless module 6 are preferably Radio Frequency Integrated Circuits (RFIC). The control unit 30 described later may also be formed within the Radio Frequency Integrated Circuit. The control unit 30 may be formed in the same Radio Frequency Integrated Circuit as a wireless module such as the first wireless module 3 or the second wireless module 6, or may be a separate circuit. Accordingly, the control unit 30 is also referred to as a control circuit.

[0019] The shared antenna 1 is capable of transmitting and receiving signals in at least a first frequency band and a second frequency band. In FIG. 1, the shared antenna 1 is configured as a component of the wireless device 101, but the shared antenna 1 may be a component external to the wireless device 101.

[0020] The first SPDT switch 2 and the second SPDT switch 5 are examples of Radio Frequency (RF) switches.

[0021] <A-2. Operation> The control unit 30 controls the first SPDT switch 2 and the second SPDT switch 5 in accordance with the frequency band of the signal transmitted and received by the wireless device 101, thereby preventing the signal from leaking to an unintended wireless module. Hereinafter, the control of the first SPDT switch 2 and the second SPDT switch 5 by the control unit 30 will be described.

[0022] FIG. 1 shows a state when the wireless device 101 receives a signal in the first frequency band. When determining that the shared antenna 1 has received a signal in the first frequency band, the control unit 30 connects the input terminal of the first SPDT switch 2 to the first output terminal, and connects the input terminal of the second SPDT switch 5 to the second output terminal. Note that in this specification, the expression "connect" includes maintaining the connection when the connection is already in an originally connected state.

[0023] In other words, in the first radio unit 21, which uses the first frequency band as its operating frequency, the first SPDT switch 2 is controlled so that the shared antenna 1 is connected to the first radio module 3. Also, in the second radio unit 22, which does not use the first frequency band as its operating frequency, the second SPDT switch 5 is controlled so that the shared antenna 1 is connected to the second open circuit 7.

[0024] As a result, the shared antenna 1 is electrically connected to the first radio module 3 via the first SPDT switch 2 and to the second open circuit 7 via the second SPDT switch 5. Consequently, the signal in the first frequency band received by the shared antenna 1 is received only by the first radio module 3, which uses the first frequency band as its operating frequency, without leaking to the second radio module 6.

[0025] The control of the first SPDT switch 2 and the second SPDT switch 5 when transmitting a signal from the first wireless module 3 is the same as described above. That is, when transmitting a signal in the first frequency band from the first wireless module 3, the control unit 30 performs the same control on the first SPDT switch 2 and the second SPDT switch 5 as when the shared antenna 1 receives a signal in the first frequency band.

[0026] Figure 2 shows the state when the wireless device 101 receives a signal in the second frequency band. When the control unit 30 determines that the shared antenna 1 has received a signal in the second frequency band, it connects the input terminal of the first SPDT switch 2 to the second output terminal and connects the input terminal of the second SPDT switch 5 to the first output terminal.

[0027] In other words, in the second radio unit 22, which uses the second frequency band as its operating frequency, the second SPDT switch 5 is controlled so that the shared antenna 1 is connected to the second radio module 6. Also, in the first radio unit 21, which does not use the second frequency band as its operating frequency, the first SPDT switch 2 is controlled so that the shared antenna 1 is connected to the first open circuit 4.

[0028] As a result, the shared antenna 1 is electrically connected to the first open circuit 4 via the first SPDT switch 2 and to the second wireless module 6 via the second SPDT switch 5. Consequently, the signal in the second frequency band received by the shared antenna 1 is received only by the second wireless module 6, which uses the second frequency band as its operating frequency, without leaking to the first wireless module 3.

[0029] The control of the first SPDT switch 2 and the second SPDT switch 5 when transmitting a signal from the second wireless module 6 is the same as described above. That is, when transmitting a signal in the second frequency band from the second wireless module 6, the control unit 30 performs the same control on the first SPDT switch 2 and the second SPDT switch 5 as when the shared antenna 1 receives a signal in the second frequency band.

[0030] The above describes how the control unit 30 controls the state of the first SPDT switch 2 and the second SPDT switch 5 during reception and transmission of the wireless device 101. However, the control unit 30 may perform the above-described control of the first SPDT switch 2 and the second SPDT switch 5 only during either reception or transmission.

[0031] Figure 3 is a flowchart showing the operation of the control unit 30 in the wireless device 101 according to Embodiment 1. The operation of the control unit 30 will be explained again below following the flow in Figure 3. The operation of the control unit 30 described here is the wireless module switching method by the wireless device 101.

[0032] First, in step S11, the control unit 30 determines whether a high-frequency signal is being transmitted from the shared antenna 1, or whether any of the wireless modules are attempting to transmit a high-frequency signal of the operating frequency. The process in step S11 is also referred to as the determination process.

[0033] If the result of the determination in step S11 is NO, the control unit 30 repeats the process in step S11.

[0034] If the determination result in step S11 is YES, in step S12, the control unit 30 controls the switch such that only the corresponding wireless module is connected to the shared antenna 1. Here, the corresponding wireless module refers to a wireless module that uses the frequency of the high-frequency signal transmitted from the shared antenna 1 as its operating frequency, or a wireless module that is about to transmit a high-frequency signal. The process of step S11 is also referred to as a connection process.

[0035] Note that the determination process of step S11 and the connection process of step S12 may be integrated into a single connection process (step S1).

[0036] Alternatively, the determination process of step S11 may be regarded as corresponding to the "Start" of the flowchart, and the connection process of step S12 may be set as the first processing step.

[0037] After step S12, in step S2, the control unit 30 disconnects the connection between the wireless modules and the shared antenna 1 in the remaining wireless units that do not include the corresponding wireless module, and controls the RF switch such that the impedance of the connection destination of the shared antenna is infinite with respect to the frequency band of the signal transmitted from the shared antenna 1 or the signal that is about to be transmitted from the transmission module.

[0038] The flow of Fig. 3 is also applicable to wireless apparatuses 102 and 103 in the embodiments described later.

[0039] <A-3. Advantageous Effects> As described above, the wireless apparatus 101 includes a shared antenna 1, a plurality of wireless units connected in parallel to the shared antenna 1 and assigned mutually different frequency bands as their operating frequencies, and a control unit 30 that controls each of the plurality of wireless units. Each of the plurality of wireless units includes a wireless module that transmits and receives signals at the operating frequency assigned to itself, an open circuit whose impedance is infinite for signals in the operating frequency bands of other wireless units, and a switch that electrically connects to the shared antenna in a switchable manner to select either the wireless module or the open circuit.

[0040] The wireless device 101 comprises a first wireless unit 21 and a second wireless unit 22 as multiple wireless units. The wireless device 101 also comprises a first wireless module 3 provided in the first wireless unit 21 and a second wireless module 6 provided in the second wireless unit 22 as wireless modules provided in each of the multiple wireless units. The wireless device 101 also comprises a first open circuit 4 provided in the first wireless unit 21 and a second open circuit 7 provided in the second wireless unit 22 as open circuits provided in each of the multiple wireless units. The wireless device 101 also comprises a first SPDT switch 2 provided in the first wireless unit 21 and a second SPDT switch 5 provided in the second wireless unit 22 as switches provided in each of the multiple wireless units.

[0041] When a signal is transmitted from the shared antenna 1, the control unit 30 controls a switch to connect the shared antenna 1 to a wireless module in the wireless unit that uses the frequency band of the signal transmitted from the shared antenna 1 as its operating frequency, and controls a switch to connect the shared antenna 1 to an open circuit in the wireless unit that does not use the frequency band of the signal transmitted from the shared antenna 1 as its operating frequency.

[0042] This makes it possible to ensure that the signal received by the shared antenna 1 is received only by the wireless module 1 that uses that frequency band as its operating frequency, thus preventing unintended signal leakage to wireless modules. Consequently, degradation of reception sensitivity can be prevented.

[0043] Furthermore, when transmitting a signal from the wireless module of one of the multiple wireless units, the control unit 30 controls the RF switch in the wireless unit of the wireless module that transmits the signal (hereinafter referred to as the "transmission module") to connect to the transmission module, and controls the RF switch in the wireless unit that does not transmit a signal to connect to an open circuit for the shared antenna 1.

[0044] Thereby, signals transmitted from one wireless module can be prevented from leaking to other wireless modules, so that degradation of transmission strength is suppressed.

[0045] The wireless device 101 performs wireless module switching using an RF switch instead of a diplexer, which in the above example is an SPDT switch, and thus can be implemented with an inexpensive and simple configuration.

[0046] The operation of the wireless device 101 according to Embodiment 1 is the wireless module switching method according to Embodiment 1. In the wireless module switching method according to Embodiment 1, when a signal is transmitted from the shared antenna 1, a connection process of controlling the RF switch to electrically connect the wireless module to the shared antenna 1 is performed in the wireless unit that uses the frequency band of the signal transmitted from the shared antenna 1 as its operating frequency, and an open circuit process of controlling the RF switch to make the impedance of the connection destination of the shared antenna 1 infinite with respect to the frequency band of the signal transmitted from the shared antenna 1 is performed in the wireless unit that does not use the frequency band of the signal transmitted from the shared antenna 1 as its operating frequency.

[0047] As described above, according to the configuration of the present embodiment, when the antenna is shared in the wireless device 101 including the first wireless module 3 and the second wireless module 6, prevention of radio field intensity degradation can be achieved with a simple and inexpensive circuit configuration that does not use a diplexer.

[0048] <B. Embodiment 2> <B-1. Configuration> Figure 4 is a block diagram showing the configuration of a wireless device 102 according to Embodiment 2. Compared with the wireless device 101 according to Embodiment 1, the wireless device 102 is different in that it includes a first DPDT (Double-Pole Double-Throw) switch 8 and a second DPDT switch 9 in place of the first SPDT switch 2 and the second SPDT switch 5. While an SPDT switch is used as the RF switch in the wireless device 101, a DPDT switch is used as the RF switch in the wireless device 102.

[0049] The DPDT switch has two input terminals and two output terminals, and is capable of switching the connection destination of each of the two input terminals to either of the two output terminals. In the first DPDT switch 8 and the second DPDT switch 9, the first input terminal is connected to the shared antenna 1, and the second input terminal is connected to the ground.

[0050] In the example of Figure 4, the switches in both the first radio unit 21 and the second radio unit 22 are configured as DPDT switches. However, the DPDT switch and the SPDT switch may coexist in the radio apparatus, such that the switch of the first radio unit 21 is configured as a DPDT switch and the switch of the second radio unit 22 is configured as an SPDT switch.

[0051] <B-2. Operation> Figure 4 shows a state when the radio apparatus 102 receives a radio wave (signal) of a first frequency band. When determining that the signal of the first frequency band is received by the shared antenna 1, the control unit 30 performs the following operation. The control unit 30 connects the first input terminal of the first DPDT switch 8 to the first output terminal, and connects the second input terminal to the second output terminal. Further, the control unit 30 connects the first input terminal of the second DPDT switch 9 to the second output terminal, and connects the second input terminal to the first output terminal.

[0052] In other words, in the first radio unit 21 that uses the first frequency band as its operating frequency, the first DPDT switch 8 is controlled such that the connection destination of the shared antenna 1 is the first radio module 3. Further, in the second radio unit 22 that does not use the first frequency band as its operating frequency, the second DPDT switch 9 is controlled such that the connection destination of the shared antenna 1 is the second open circuit 7.

[0053] As a result, the shared antenna 1 is electrically connected to the first wireless module 3 via the first DPDT switch 8 and to the second open circuit 7 via the second DPDT switch 9. Consequently, the signal in the first frequency band received by the shared antenna 1 is received only by the first wireless module 3, which uses the first frequency band as its operating frequency, without leaking to the second wireless module 6.

[0054] The control of the first DPDT switch 8 and the second DPDT switch 9 when transmitting a signal from the first wireless module 3 is the same as described above. In other words, when transmitting a signal from the first wireless module 3, the control unit 30 performs the same control on the first DPDT switch 8 and the second DPDT switch 9 as when the shared antenna 1 receives a signal in the first frequency band.

[0055] Figure 5 shows the state when the wireless device 102 receives a signal in the second frequency band. When the control unit 30 determines that the shared antenna 1 has received a signal in the second frequency band, it connects the first input terminal of the first DPDT switch 8 to the second output terminal and connects the input terminal of the second DPDT switch 9 to the first output terminal.

[0056] In other words, in the second radio unit 22, which uses the second frequency band as its operating frequency, the second DPDT switch 9 is controlled so that the shared antenna 1 is connected to the second radio module 6. Also, in the first radio unit 21, which does not use the second frequency band as its operating frequency, the first DPDT switch 8 is controlled so that the shared antenna 1 is connected to the first open circuit 4.

[0057] As a result, the shared antenna 1 is electrically connected to the first open circuit 4 via the first DPDT switch 8 and to the second wireless module 6 via the second DPDT switch 9. Consequently, the signals in the second frequency band received by the shared antenna 1 are received only by the second wireless module 6, which uses the second frequency band as its operating frequency, without leaking to the first wireless module 3.

[0058] Control of the first DPDT switch 8 and the second DPDT switch 9 when transmitting a signal from the second wireless module 6 is also the same as described above. That is, when transmitting a signal in the second frequency band from the second wireless module 6, the control unit 30 performs the same control on the first DPDT switch 8 and the second DPDT switch 9 as when the shared antenna 1 receives a signal in the second frequency band.

[0059] <B-3. Advantageous Effects> The wireless device 102 has the same configuration as the wireless device 101 except that a DPDT switch is used as the switch of the wireless unit. Therefore, according to the wireless device 102, similarly to the wireless device 101, it is possible to suppress deterioration of reception sensitivity or deterioration of transmission intensity.

[0060] Furthermore, in the wireless device 102, the DPDT switch electrically connects the wireless module that is not connected to the shared antenna 1 to the ground, so that deterioration of signal intensity can be suppressed with higher performance than the wireless device 101 according to the first embodiment.

[0061] <C. Third Embodiment> In the first and second embodiments, a wireless device in which two wireless modules with mutually different operating frequencies share one antenna has been described. In the wireless device of the present disclosure, the number of wireless modules with mutually different operating frequencies that share one antenna is not limited to 2, and may be 3 or more. Therefore, in the third embodiment, a wireless device in which three wireless modules with mutually different operating frequencies share one antenna will be described.

[0062] <C-1. Configuration> Figure 6 is a block diagram showing the configuration of a wireless device 103 according to the third embodiment. The wireless device 103 includes a shared antenna 1, a first wireless unit 21, a second wireless unit 22, a third wireless unit 23, and a control unit 30. In the present embodiment, the shared antenna 1 is capable of transmitting and receiving signals in the third frequency band in addition to transmitting and receiving signals in the first frequency band and the second frequency band.

[0063] A high-frequency transmission line is connected to the shared antenna 1. In other words, one end of the high-frequency transmission line is connected to the shared antenna 1. The other end of the high-frequency transmission line branches into three, with the first branch connected to the first radio unit 21, the second branch connected to the second radio unit 22, and the third branch connected to the third radio unit 23. In other words, the first radio unit 21, the second radio unit 22, and the third radio unit 23 are connected in parallel to the shared antenna 1.

[0064] The first wireless unit 21 comprises a first DPDT switch 8, a first wireless module 3, and a first open circuit 10. The first output terminal of the first DPDT switch 8 is connected to the first wireless module 3, and the second output terminal is connected to the first open circuit 10. The first open circuit 10 is a circuit whose impedance is infinite for the second and third frequency bands.

[0065] The second wireless unit 22 comprises a second DPDT switch 9, a second wireless module 6, and a second open circuit 11. The first output terminal of the second DPDT switch 9 is connected to the second wireless module 6, and the second output terminal is connected to the second open circuit 11. The second open circuit 11 is a circuit whose impedance is infinite for the first frequency band and the third frequency band.

[0066] The third wireless unit 23 comprises a third DPDT switch 12, a third wireless module 13, and a third open circuit 14. The first output terminal of the third DPDT switch 12 is connected to the third wireless module 13, and the third output terminal is connected to the third open circuit 14. The third open circuit 14 is a circuit whose impedance is infinite for the first and second frequency bands. In the first DPDT switch 8, the second DPDT switch 9, and the third DPDT switch 12, one input terminal is connected to the shared antenna 1, and the other input terminal is grounded.

[0067] Thus, the wireless device 103 is configured to share an antenna among the first wireless module 3, the second wireless module 6, and the third wireless module 13, which operate on different frequencies.

[0068] The first wireless module 3, the second wireless module 6, and the third wireless module 13 are preferably radio frequency integrated circuits. The control unit 30 may be formed in the same radio frequency integrated circuit as at least one of the first wireless module 3, the second wireless module 6, and the third wireless module 13, or may be a separate circuit.

[0069] The shared antenna 1 is capable of transmitting and receiving signals in at least a first frequency band, a second frequency band, and a third frequency band.

[0070] The first DPDT switch 8, the second DPDT switch 9, and the third DPDT switch 12 are examples of RF switches.

[0071] <C-2. Operation> Figure 6 illustrates a state when the wireless device 103 receives a signal in the first frequency band. When determining that the shared antenna 1 has received a signal in the first frequency band, the control unit 30 performs the following operations. The control unit 30 connects the first input terminal of the first DPDT switch 8 to the first output terminal, and connects the second input terminal to the second output terminal. Further, the control unit 30 connects the first input terminal to the second output terminal and connects the second input terminal to the first output terminal in each of the second DPDT switch 9 and the third DPDT switch 12.

[0072] In other words, in the first wireless unit 21 that uses the first frequency band as its operating frequency, the first DPDT switch 8 is controlled such that the shared antenna 1 is connected to the first wireless module 3. Further, in the second wireless unit 22 and the third wireless unit 23 that do not use the first frequency band as their operating frequency, the second DPDT switch 9 and the third DPDT switch 12 are controlled such that the shared antenna 1 is connected to the second open circuit 7 and the third open circuit 14, respectively.

[0073] As a result, the shared antenna 1 is electrically connected to the first radio module 3 via the first DPDT switch 8, to the second open circuit 7 via the second DPDT switch 9, and to the third open circuit 14 via the third DPDT switch 12. Consequently, signals in the first frequency band received by the shared antenna 1 are received only by the first radio module 3, which uses the first frequency band as its operating frequency, without leaking to the second radio module 6 or the third radio module 13.

[0074] The control of the first DPDT switch 8, the second DPDT switch 9, and the third DPDT switch 12 when transmitting a signal from the first wireless module 3 is the same as described above. In other words, when transmitting a signal from the first wireless module 3, the control unit 30 performs the same control on the first DPDT switch 8, the second DPDT switch 9, and the third DPDT switch 12 as when the shared antenna 1 receives a signal in the first frequency band.

[0075] Figure 7 shows the state when the wireless device 103 receives a signal in the second frequency band. When the control unit 30 determines that it has received a signal in the second frequency band at the shared antenna 1, it performs the following operations: The control unit 30 connects the first input terminal of the second DPDT switch 9 to the first output terminal and the second input terminal to the second output terminal. In addition, the control unit 30 connects the first input terminal of the first DPDT switch 8 and the third DPDT switch 12 to the second output terminal and the second input terminal to the first output terminal.

[0076] In other words, in the second radio unit 22, which uses the second frequency band as its operating frequency, the second DPDT switch 9 is controlled so that the shared antenna 1 is connected to the second radio module 6. Also, in the first radio unit 21 and the third radio unit 23, which do not use the second frequency band as their operating frequency, the first DPDT switch 8 and the third DPDT switch 12 are controlled so that the shared antenna 1 is connected to the first open circuit 10 and the third open circuit 14, respectively.

[0077] As a result, the shared antenna 1 is electrically connected to the second radio module 6 via the second DPDT switch 9, to the first open circuit 10 via the first DPDT switch 8, and to the third open circuit 14 via the third DPDT switch 12. Consequently, the signals in the second frequency band received by the shared antenna 1 are received only by the second radio module 6, which uses the second frequency band as its operating frequency, without leaking to the first radio module 3 or the third radio module 13.

[0078] The control of the first DPDT switch 8, the second DPDT switch 9, and the third DPDT switch 12 when transmitting a signal from the second wireless module 6 is the same as described above. In other words, when transmitting a signal from the second wireless module 6, the control unit 30 performs the same control on the first DPDT switch 8, the second DPDT switch 9, and the third DPDT switch 12 as when the shared antenna 1 receives a signal in the second frequency band.

[0079] Figure 8 shows the state when the wireless device 103 receives a signal in the third frequency band. When the control unit 30 determines that it has received a signal in the third frequency band at the shared antenna 1, it performs the following actions: The control unit 30 connects the first input terminal of the third DPDT switch 12 to the first output terminal and the second input terminal to the second output terminal. In addition, the control unit 30 connects the first input terminal of the first DPDT switch 8 and the second DPDT switch 9 to the second output terminal and the second input terminal to the first output terminal.

[0080] In other words, in the third radio unit 23, which uses the third frequency band as its operating frequency, the third DPDT switch 12 is controlled so that the shared antenna 1 is connected to the third radio module 13. Also, in the first radio unit 21 and the second radio unit 22, which do not use the third frequency band as their operating frequency, the first DPDT switch 8 and the second DPDT switch 9 are controlled so that the shared antenna 1 is connected to the first open circuit 10 and the second open circuit 11, respectively.

[0081] Thereby, the shared antenna 1 is electrically connected to the third wireless module 13 via the third DPDT switch 12, electrically connected to the first open circuit 10 via the first DPDT switch 8, and electrically connected to the second open circuit 11 via the second DPDT switch 9. As a result, the signal in the third frequency band received by the shared antenna 1 does not leak to the first wireless module 3 and the second wireless module 6, and is received only by the third wireless module 13 that uses the third frequency band as its operating frequency.

[0082] The control of the first DPDT switch 8, the second DPDT switch 9, and the third DPDT switch 12 when transmitting a signal from the third wireless module 13 is also the same as described above. That is, when transmitting a signal from the third wireless module 13, the control unit 30 performs the same control on the first DPDT switch 8, the second DPDT switch 9, and the third DPDT switch 12 as when the shared antenna 1 receives a signal in the third frequency band.

[0083] In the present embodiment, at least one of the first DPDT switch 8, the second DPDT switch 9, and the third DPDT switch 12 may be an SPDT switch.

[0084] <C-3. Effect> The wireless device 103 according to Embodiment 3 is the same as the wireless device 102 according to Embodiment 2, except that the number of wireless modules in which the first wireless unit 21, the second wireless unit 22, and the third wireless unit 23 are connected in parallel to the shared antenna 1 is three. Therefore, according to the wireless device 103, even in a configuration where three wireless modules using three mutually different frequency bands share an antenna, it is possible to suppress degradation of reception sensitivity or degradation of transmission intensity with a low-cost and simple configuration.

[0085] The preferred embodiments and the like have been described in detail above, but the present invention is not limited to the above-described embodiments and the like, and various modifications and substitutions can be made to the above-described embodiments and the like without departing from the scope recited in the claims. [Description of Reference Signs]

[0086] 1 Shared antenna, 2 First SPDT switch, 3 First wireless module, 4 First open circuit, 5 Second SPDT switch, 6 Second wireless module, 7 Second open circuit, 8 First DPDT switch, 9 Second DPDT switch, 10 First open circuit, 11 Second open circuit, 12 Third DPDT switch, 13 Third wireless module, 14 Third open circuit, 21 First wireless unit, 22 Second wireless unit, 23 Third wireless unit, 30 Control unit, 101 Wireless device, 102 Wireless device, 103 Wireless device.

Claims

1. Shared antenna and Multiple radio units connected in parallel to the shared antenna, each assigned a different frequency band as its operating frequency, The system comprises a control unit that controls each of the aforementioned plurality of wireless units, Each of the aforementioned multiple wireless units is A wireless module that transmits and receives signals on the aforementioned operating frequency assigned to itself, An open circuit in which the impedance becomes infinite for signals in the operating frequency band of other wireless sections, The system includes an RF switch that electrically connects to the shared antenna in a way that allows switching between the wireless module and the open circuit, The control unit, When a signal is transmitted from the shared antenna, the wireless unit sets the frequency band of the signal transmitted from the shared antenna to the operating frequency. The RF switch is controlled so that the shared antenna is connected to the wireless module. In the wireless unit, in which the frequency band of the signal transmitted from the shared antenna is not used as the operating frequency, the RF switch is controlled so that the connection destination of the shared antenna is the open circuit. Radio equipment.

2. Shared antenna and Multiple radio units connected in parallel to the shared antenna, each assigned a different frequency band as its operating frequency, The system comprises a control unit that controls each of the aforementioned plurality of wireless units, Each of the aforementioned multiple wireless units is A wireless module that transmits and receives signals on the aforementioned operating frequency assigned to itself, An open circuit in which the impedance becomes infinite for signals in the operating frequency band of other wireless sections, The system includes an RF switch that electrically connects to the shared antenna in a way that allows switching between the wireless module and the open circuit, The control unit, When transmitting a signal from the wireless module of any of the aforementioned multiple wireless units, In the wireless section of the wireless module that transmits the aforementioned signal, The RF switch is controlled so that the shared antenna is connected to the wireless module. In the wireless unit that does not transmit the aforementioned signal, the RF switch is controlled so that the connection destination of the shared antenna is the open circuit. Radio equipment.

3. The RF switch is at least one of an SPDT switch and a DPDT switch. The wireless device according to claim 1 or claim 2.

4. The DPDT switch is The wireless module and the open circuit that are not electrically connected to the shared antenna are electrically connected to ground. The wireless device according to claim 3.

5. Shared antenna and The system comprises a plurality of radio units connected in parallel to the shared antenna, each having a different frequency band assigned to it as its operating frequency, Each of the aforementioned multiple wireless units is A wireless module that transmits and receives signals on the aforementioned operating frequency assigned to itself, The system includes an RF switch that switches between having an electrical connection between the wireless module and the shared antenna. A method for switching wireless modules in a wireless device, When a signal is transmitted from the shared antenna, the wireless unit, which uses the frequency band of the signal transmitted from the shared antenna as the operating frequency, performs a connection process to control the RF switch so as to electrically connect the wireless module to the shared antenna. In the wireless unit, where the frequency band of the signal transmitted from the shared antenna is not used as the operating frequency, an open-circuit process is performed to control the RF switch so that the impedance of the connection destination of the shared antenna becomes infinite with respect to the frequency band of the signal transmitted from the shared antenna. How to switch wireless modules.

6. Each of the aforementioned multiple wireless units further includes an open circuit whose impedance becomes infinite with respect to signals in the frequency band used by the other wireless units. In the aforementioned open circuit process, in the wireless unit, where the frequency band of the signal transmitted from the shared antenna is not the operating frequency, the RF switch is controlled to electrically connect the open circuit to the shared antenna. A method for switching wireless modules according to claim 5.

7. In the aforementioned opening process, in the wireless unit where the frequency band of the signal transmitted from the shared antenna is not the operating frequency, the RF switch is controlled to electrically connect the wireless module to ground. A method for switching wireless modules according to claim 5 or claim 6.

8. Shared antenna and The system comprises a plurality of radio units connected in parallel to the shared antenna, each having a different frequency band assigned to it as its operating frequency, Each of the aforementioned multiple wireless units is A wireless module that transmits and receives signals on the aforementioned operating frequency assigned to itself, The system includes an RF switch that switches between having an electrical connection between the wireless module and the shared antenna. A method for switching wireless modules in a wireless device, When transmitting a signal from the wireless module of any of the plurality of wireless units, the wireless unit of the transmission module, which is the wireless module that transmits the signal, performs a connection process to control the RF switch so as to electrically connect the transmission module to the shared antenna. In the wireless unit that does not include the transmission module, an open-circuit process is performed to control the RF switch so that the impedance of the connection destination of the shared antenna becomes infinite with respect to the frequency band of the signal transmitted from the transmission module. How to switch wireless modules.

9. Each of the aforementioned multiple wireless units further includes an open circuit whose impedance becomes infinite with respect to signals in the frequency band used by the other wireless units. In the aforementioned opening process, the RF switch is controlled in the wireless unit that does not have the transmission module to electrically connect the open circuit to the shared antenna. A method for switching wireless modules according to claim 8.

10. In the aforementioned opening process, the RF switch is controlled in the wireless unit that does not have the transmission module to electrically connect the wireless module to ground. A method for switching wireless modules according to claim 8 or claim 9.

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