JP2004356739A - Radio communication apparatus and antenna switching method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To correspond to a radio communication system for performing consecutive receiving operations, and to perform appropriate antenna switching by a simple configuration. <P>SOLUTION: In a control unit 110, when a communication state detector 109 determines that an apparatus is in a non-communication state, an out-of-zone determining section 107 determines that a reception signal level measured by a reception signal measuring section 106 is lowered, and the apparatus reaches an out-of-zone condition and an out-of-zone determining timer 108 starts; the timer 108 determines whether the reception signal level reaches the out-of-zone condition at a predetermined interval within a predetermined timer setting time for timing the duration time of the out-of-zone condition. Every time it is determined that the signal level reaches the out-of-zone condition, an antenna switching section 111 outputs an antenna switching control signal to an antenna switch 103, and the antenna is switched between a first antenna 101 and a second antenna 102. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a wireless communication device having a plurality of antennas for performing transmission and reception, and an antenna switching method thereof.
[0002]
[Prior art]
For example, a wireless communication device such as a mobile phone can communicate while moving within a service area formed by a plurality of base stations.
[0003]
After the user turns on the power of this type of wireless communication apparatus, the wireless communication apparatus determines whether or not the own station is located within the service area of the base station. This determination is made based on whether control information from the base station can be received. In order to constantly and surely promote control information transmitted from the base station, a received signal having a threshold level or more is required.
[0004]
At this time, if the control information can be received beyond the threshold level, it is determined that the own station is located within the service area of the base station. After that, the position information of the own station is transmitted to the base station. At the same time, control information such as identification information of the received base station is stored. As a result, the mobile phone is connected to the wireless line via the base station and enters a standby state. In this standby state, the mobile phone can receive a call by intermittently receiving only the slot at the designated timing among the signals transmitted from the base station at a constant cycle.
[0005]
On the other hand, if the control information cannot be received beyond the threshold level, it is determined that the own station is located outside the service area. If the own station is located outside the service area, it is determined whether the own station is located within the service area or outside the service area. This determination is repeated until the own station moves into the service area of the base station and can receive control information.
[0006]
In order to effectively receive the control information as described above, a radio communication apparatus selects a propagation path that causes less deterioration in characteristics of a received signal due to interference waves or fading. As a method of selecting the propagation path, for example, there is antenna diversity. This is a method in which a plurality of antennas are provided, the signal levels received by the respective antennas are compared, and reception is performed by switching to the antenna that can obtain a higher received signal level.
[0007]
As a specific method, in a wireless communication apparatus such as a mobile phone of a TDMA (Time Division Multiple Access) method, switching of a plurality of antennas is performed by using an idle time such as a reception empty slot or a transmission slot. In some cases, the level of a received signal received by each antenna is measured, the measured values are compared, and the antenna is switched to an antenna capable of obtaining a larger received signal.
[0008]
In a wireless communication system in which operations such as CDMA (Code Division Multiple Access) are continuous, antenna switching is performed using idle time such as a reception empty slot or a transmission slot as in the TDMA method. I can't. Therefore, when performing diversity by providing two or more antennas, at least two or more receivers and reception signal level detection means are provided, and the levels of the reception signals measured in the respective systems are compared at the same time. A method of performing diversity by selecting a higher antenna or a method of providing a certain threshold value in a received electric field level and performing antenna switching only by a determination when the value falls below the threshold value are used.
[0009]
As an example of a method of performing antenna switching based on the determination of the threshold value, there is a method disclosed in Japanese Patent Application Laid-Open No. 7-131396 (Patent Document 1). In this conventional example, the antenna diversity is performed every time the reception electric field level falls below a certain threshold value or when a certain criterion is set. That is, in the diversity receiving method described in Patent Document 1, when a reception is performed by switching an antenna to one of a plurality of antennas, a predetermined threshold level is provided for a reception power level of the antenna, and reception is performed by a selected antenna. When the received signal level is lower than the threshold, switching to another antenna is performed, and when the received signal level after switching is lower than before switching, the antenna is returned to the originally selected antenna again. . Further, by making the threshold value variable, the diversity effect is further enhanced.
[0010]
[Patent Document 1]
JP-A-7-131396
[0011]
[Problems to be solved by the invention]
However, the following problems may occur in the above-described conventional wireless communication device.
[0012]
2. Description of the Related Art In a wireless communication system such as a CDMA system, in order to perform diversity by comparing the levels of received signals received by respective antennas, at least two or more systems of receivers and received signal level detecting means are required. And the processing in the control unit is complicated.
[0013]
Also, in the diversity receiving method described in Patent Document 1, a threshold value is provided for a received signal level, antenna switching is performed when the received signal level falls below the threshold value, and when the received signal level after switching is lower than before the switching, To return to the selected antenna. This method is effective for a wireless communication system in which the operation is continuous like the CDMA system. However, if the antenna is not switched once, the received signal level at the switched antenna is not known. For example, when the received signal level at the switched antenna is extremely low, sudden communication disconnection occurs during communication. There is a risk.
[0014]
On the other hand, even during non-communication, antenna switching is performed when the received signal level falls below the threshold, and when the level of the received signal received by the switched antenna is low, the antenna is returned to the originally selected antenna again. Therefore, it is possible to select an antenna that always provides a higher received signal level. However, despite sufficient reception by the antenna before switching, an antenna switching operation occurs, and an operation of switching back to the original antenna occurs depending on the reception level after switching, so that the switching efficiency is poor. Become. In addition, depending on the threshold value, the state becomes out of service area after the switching, and during that time, there is a time zone in which the call connection is disabled.
[0015]
The present invention has been made in view of the above circumstances, is applicable to a wireless communication system that performs a continuous reception operation, and realizes appropriate antenna switching with a simple configuration without increasing the circuit scale. It is an object of the present invention to provide a wireless communication apparatus and an antenna switching method capable of shortening out-of-service time and improving a call connection rate.
[0016]
[Means for Solving the Problems]
A wireless communication device according to the present invention is a wireless communication device having a plurality of antennas, wherein an antenna switching unit that switches the plurality of antennas, and a reception signal level received by any one of the plurality of antennas. Receiving signal measuring means for measuring, out-of-service determining means for determining whether or not out of communication range based on the measurement result of the receiving signal measuring means; determining that the received signal level has reached out-of-service condition by the out-of-service determining means In this case, when the out-of-service condition is reached, the out-of-service determination time-measurement means, the communication status detection means for detecting the communication status of the wireless communication device, and the non-communication status When the out-of-service determination means determines that the out-of-service condition has been reached and the out-of-service determination timer starts, In the setting of the counting time, in which each time it is determined that measures the reception signal level at predetermined intervals has reached the out-of-service condition, and an antenna switching control means for switching the plurality of antennas.
[0017]
According to the above configuration, for example, even in a wireless communication system that performs a continuous reception operation such as a CDMA system, antenna switching can be performed with a simple configuration without providing two systems of reception signal level detection means. And antenna diversity can be realized. Further, even when the reception signal level reaches the out-of-service condition, the continuation time when the out-of-service condition is reached is measured, and the antenna switching control is performed within a predetermined time set by the time measurement, thereby shifting to the out-of-service state. Can be switched to the appropriate antenna. Further, if the reception signal level at either antenna becomes equal to or more than the out-of-service condition within the predetermined time set time, by using the antenna selected at this time, the mobile terminal shifts to the standby state in the service area, thereby It is possible to reduce the state. Further, even after the out-of-service condition is reached, the antenna switching control is performed, and once the received signal level reaches the out-of-service condition or higher (recovery range in the service area), a transition is made to the standby state with the antenna selected at that time, so that Return to the state is quick, and as a result, the call connection rate can be improved.
[0018]
Further, as a second configuration, the wireless communication apparatus is configured to include a foldable housing, and an opening / closing detection unit configured to detect opening / closing of the housing, and an antenna corresponding to an opening / closing state of the housing. Antenna switching condition storage means for storing a switching condition, wherein the antenna switching control means performs switching in each of a state where the housing is open and a state where the housing is closed according to the antenna switching condition. Are limited.
[0019]
According to the above configuration, when the wireless communication device has a foldable housing, the antenna that switches between the open state and the closed state according to the antenna switching condition is limited, so that the housing can be opened and closed. Accordingly, it is possible to perform switching limited to only appropriate antennas having good antenna characteristics. In this case, unnecessary antenna switching can be reduced, and efficient antenna switching can be realized.
[0020]
Further, as a third configuration, the wireless communication device described above is configured to include a foldable housing, and includes opening / closing detection means for detecting opening / closing of the housing. When the opening / closing of the casing is detected by the detecting means, based on the detection result of the communication state detecting means, when the wireless communication apparatus is in the communication state, the wireless communication apparatus selects an antenna suitable for the communication state, and selects the antenna in the non-communication state. In such a case, an antenna suitable for a non-communication state is selected each time the opening / closing of the housing is detected.
[0021]
According to the above configuration, an antenna suitable for the communication state can be selected in the communication state, and good communication can be established. In addition, in a non-communication state such as a standby state, when the housing is opened and closed, the antenna is returned to an antenna suitable for the non-communication state. First you can choose. As a result, the out-of-service time can be reduced and the call connection rate can be improved.
[0022]
Further, as a fourth configuration, the wireless communication device described above, further comprising: a call connection state detection unit that detects a call connection state of the wireless communication device, wherein the antenna switching control unit includes a call connection state detection unit. Based on the detection result, the current antenna connection is maintained when the wireless communication apparatus is in the communication state and the call connection processing is being performed, and after the call connection processing is completed and the call connection is established, the antenna switching suitable for the actual use state is performed. Things.
[0023]
According to the above configuration, when in a non-communication state such as a standby state, appropriate antenna switching can be realized with a simple configuration similarly to the above, and when a call connection process is being performed in a communication state, the selected antenna connection is maintained. Thus, an appropriate communication operation can be performed. After the call connection is established, it is possible to switch to an antenna suitable for an actual use state such as a normal communication state. Therefore, it is possible to select an appropriate antenna according to each operation state, and to stabilize the call connection systematically.
[0024]
Further, the wireless communication device of the present invention is applicable to portable terminal devices such as a portable telephone device and a portable information terminal having a communication function, and realizes appropriate antenna switching with a simple configuration in these portable terminal devices. it can. Also, the wireless communication device of the present invention is applicable to a wireless communication device that performs wireless communication with a base station in a wireless communication system such as a mobile communication system, and performs wireless communication that performs a continuous reception operation. It is also possible to provide a wireless communication system that can be adapted to a system, can realize appropriate antenna switching with a simple configuration, and can shorten out-of-service time and improve the call connection rate.
[0025]
An antenna switching method according to the present invention is an antenna switching method in a wireless communication device having a plurality of antennas, wherein a communication state detecting step of detecting a communication state of the wireless communication device, and any one of the plurality of antennas In the out-of-service determination step of measuring the received signal level received in to determine whether it is out of the communication range, and when a non-communication state is detected in the communication state detection step, the out-of-service determination step When it is determined that the received signal level has reached the out-of-service condition, an out-of-service time counting step for counting the duration in which the out-of-service condition has been reached, and within a predetermined time setting time after the start of the time measurement of the out-of-service condition, The plurality of antennas are turned off each time the reception signal level is measured at intervals and it is determined that the out-of-service condition is reached. An antenna switching control step of changing, and has a.
[0026]
According to the above procedure, it is possible to cope with a wireless communication system that performs a continuous reception operation, and appropriate switching of antennas can be realized with a simple configuration without increasing the circuit scale. In addition, such an appropriate antenna switching can shorten the out-of-service time and improve the call connection rate.
[0027]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described below. The wireless communication device according to this embodiment is applied to a mobile terminal device such as a mobile phone device or a mobile information terminal having a communication function. Further, the wireless communication device of the present embodiment performs wireless communication with a base station in a wireless communication system such as a mobile communication system, for example, and can transmit and receive various information.
[0028]
(1st Embodiment)
FIG. 1 is a block diagram showing a configuration of the wireless communication device according to the first embodiment of the present invention. In the first embodiment, an example of a wireless communication device including two antennas will be described.
[0029]
The wireless communication device 100 according to the first embodiment includes a first antenna 101, a second antenna 102, an antenna switch 103, an RF unit 104, a modem 105, a control unit 110, and an antenna switching unit 111. It is configured with. The control unit 110 includes a reception signal measurement unit 106, an out-of-service determination unit 107, an out-of-service determination timer 108, and a communication state detection unit 109.
[0030]
The wireless communication device 100 transmits and receives a high-frequency signal via the first antenna 101 or the second antenna 102. At the time of reception, one of the first antenna 101 and the second antenna 102 is selected by the antenna switch 103, and only the radio wave received from the selected antenna is sent to the RF unit 104.
[0031]
The antenna switch 103 corresponds to an example of an antenna switching unit, and switches between the first antenna 101 and the second antenna 102 according to a switching control signal from the antenna switching unit 111.
[0032]
The RF unit 104 down-converts a radio signal received by the first antenna 101 or the second antenna 102 to a baseband frequency during reception, and converts a baseband signal transmitted as a transmission signal from the control unit 110 to a radio frequency band during transmission. Upconvert to. The modulation and demodulation section 105 demodulates a reception signal from the RF section 104 and modulates a transmission signal from the control section 110.
[0033]
For example, when the wireless communication apparatus 100 is a mobile station apparatus such as a mobile phone, in a communication state, a reception signal demodulated by the modulation and demodulation section 105 is input to a voice processing section (not shown), and a received voice is emitted outside. You. Further, when in the non-communication state, the received signal demodulated by the modem 105 is input to the control unit 110 to determine whether the own station is in the communication range with the base station or out of the communication range, and the received signal is The strength and signal quality are measured.
[0034]
The control unit 110 controls the entire wireless communication device 100. In the control unit 110, the received signal measuring unit 106 corresponds to an example of a received signal measuring unit, and is received by the first antenna 101 or the second antenna 102, and transmitted to the modem 105 via the antenna switch 103 and the RF unit 104. The received signal level such as the strength and signal quality of the output received signal is measured.
[0035]
The out-of-service determining unit 107 corresponds to an example of an out-of-service determining unit, and determines whether the received signal level has reached the out-of-service condition based on the measurement result of the received signal measuring unit 106. The out-of-service determination timer 108 corresponds to an example of an out-of-service determination timer, and determines that the reception signal received by the first antenna 101 or the second antenna 102 has reached the out-of-service condition determined by the out-of-service determination unit 107. It starts when it reaches and measures the duration of the out-of-service condition.
[0036]
Here, even if the received signal level has been determined to have reached the out-of-service condition by the out-of-service determination unit 107, the control unit 110 determines in advance the duration of the time that the out-of-service condition has been reached by counting the out-of-service determination timer 108. If the time is within a predetermined timer set time (timed set time), it is not determined that the received signal is degraded, but is considered to be in a normal state, and the fact is reported. If the duration for which the out-of-service condition has been reached once exceeds the timer set time, it is determined that the received signal is degraded, the fact is reported, and the state shifts to the out-of-service state. Thus, even if it is determined that the out-of-service condition has been reached within a predetermined timer set time, it is possible to maintain the service state.
[0037]
The communication state detection unit 109 corresponds to an example of a communication state detection unit, and determines whether the wireless communication device 100 is in a communication state or a non-communication state. The antenna switching unit 111 corresponds to an example of an antenna switching control unit, and generates an antenna switching control signal according to the state of the received signal level and outputs the signal to the antenna switch 103.
[0038]
Here, when communication state detecting section 109 determines that the communication state is not in communication, control section 110 determines the level of a received signal received by out-of-coverage determining section 107 on the antenna selected from first antenna 101 and second antenna 102. Is determined to have reached the predetermined out-of-service condition, and the out-of-service determination timer 108 is started. If the received signal level reaches the out-of-service condition at a certain interval within a timer set time determined by the out-of-service determination timer 108, I do. As a result, each time it is determined that the out-of-service condition has been reached, the antenna switching unit 111 generates an antenna switching control signal and outputs the signal to the antenna switch 103.
[0039]
Next, the operation of the wireless communication device 100 configured as described above will be described. FIG. 2 is a flowchart illustrating the operation of the wireless communication device according to the first embodiment, and FIG. 3 is a state transition diagram illustrating the operation of the wireless communication device according to the first embodiment. The procedure of FIG. 2 is mainly executed by the control unit 110.
[0040]
First, received signal deterioration detection is performed by the received signal measuring unit 106 in a standby state (step S101). Here, first, the communication state detection unit 109 determines whether the wireless communication apparatus 100 is in a communication state or a non-communication state, and when it is determined that the wireless communication apparatus 100 is in a non-communication state, the first antenna 101 or the second antenna The received signal level received at 102 is measured by the received signal measuring unit 106, and the out-of-service determining unit 107 determines whether the mobile terminal is within the service area or outside the service area based on the measurement result of the received signal measuring unit 106. Here, when a predetermined out-of-service condition is reached, it is determined that the out-of-service condition is out of service and deterioration of the received signal is detected.
[0041]
In step S101, when the received signal deterioration is detected, the out-of-service determination timer 108 is started, and the duration of reaching the out-of-service condition is counted (step S102). Thereafter, a received signal is detected (step S103).
[0042]
When the received signal is detected in step S103, the received signal level detected by the received signal measuring unit 106 is measured, and the out-of-service determining unit 107 determines whether the mobile terminal is out of service or in service based on the received signal level (step S104). .
[0043]
If it is determined in step S104 that the mobile station is out of the service area, an antenna switching control signal is generated by the antenna switching unit 111 and output to the antenna switch 103. The antenna switch 103 switches to the other antenna different from the currently selected antenna based on the antenna switching control signal (step S105).
[0044]
After switching the antenna, it is determined whether or not the timer set time of the out-of-coverage determination timer 108 remains (step S106). In step S106, when the out-of-service determination timer setting time remains, even if the reception signal strength and the signal quality of the reception signal detected in step S103 have reached the out-of-service condition, the reception signal deterioration report is not performed as the out-of-service report. A report (report of being in range) is made (step S107), and the process returns to step S103 to detect a received signal again.
[0045]
On the other hand, if the out-of-service determination timer setting time has not been left in step S106, a received signal deterioration report is made (step S108), and the state shifts to the out-of-service state.
[0046]
If it is determined in step S104 that the mobile station is within the service area, a normal report (report within the service area) is performed without reporting the received signal deterioration (step S109), and the timer of the out-of-service determination timer 108 is stopped (step S110). Then, the state shifts to a normal standby state.
[0047]
After the reception signal deterioration is reported in step S108 and the mobile terminal shifts to the out-of-service state, the strength and signal quality of the reception signals received by the first antenna 101 and the second antenna 102 are determined by the out-of-service determination unit 107. The antenna switching is continuously performed until the antenna reaches the service area, and when the antenna returns to the service area, the mobile terminal shifts to a standby state using the antenna.
[0048]
FIG. 3 shows a state transition with respect to a change in the received signal level in the first embodiment. In FIG. 3, when the reception signal level changes from the state A having the high reception signal level to the state B having the low reception signal level while waiting, the reception signal is below the threshold L outside the service area, so that the reception signal deterioration detection is performed in step S101 in FIG. In step S102, the out-of-service determination timer 108 is started. In step S103, a reception signal is detected, and the state is changed to state C.
[0049]
In state C, since the received signal level detected in step S103 of FIG. 2 is lower than the in-range to out-of-range threshold L, it is determined that the in-range determination is in step S104, and the antenna is switched in step S105. Further, since it is determined in step S106 that the set time for the out-of-range determination timer remains, a normal report is made in step S107, and the process shifts to the reception signal detection in step S103 again to enter the state D.
[0050]
In state D, as a result of detecting the received signal in step S103 of FIG. 2, the received signal level has become equal to or more than the in-service area → out-of-service threshold value L. Therefore, it is determined in the in-service area in step S104 that the vehicle is in the in-service area. (Report within range). Further, in step S110, the timer of the out-of-service area determination timer 108 is stopped, and the mode shifts to a normal standby state.
[0051]
Here, in the threshold of the control unit 110, the threshold L within the service area and the threshold L outside the service area and the threshold value H outside the service area generally have a hysteresis HS as shown in FIG. Further, when the received signal has reached the out-of-service level, the out-of-service determination timer 108 operates. If the inside-to-outside threshold L and the outside-to-coverage threshold H are the same, the wireless communication device exists just near the boundary between the outside and inside the area, and when the received signal level is near the threshold, the outside and inside states are repeated. Therefore, in order to prevent this, the above-described hysteresis HS is provided. In addition, by the operation of the out-of-service determination timer 108, even if the received signal level temporarily falls below the in-service → out-of-service threshold L, if the service level becomes equal to or more than the in-service → out-of-service threshold L within the out-of-service determination timer set time, it is possible to shift to the normal standby state. In the case where the received signal is temporarily out of the service area due to a fading environment or the like, the mobile station does not immediately go out of the service area.
[0052]
Also, if the reception signal level does not exceed the in-service area → out-of-service threshold L and the duration time becomes equal to or more than the out-of-service determination timer set time, the wireless communication apparatus shifts to the out-of-service state, and the reception signal level is out of the service area → in-service threshold H. It will not return to the area unless it becomes the above.
[0053]
As described above, in the first embodiment, the out-of-service determination timer 108 is activated when the received signal falls below the service range → out-of-service threshold L, and the received signal level is measured within the set time of the out-of-service determination timer. Each time it is determined that the vehicle is in the out-of-service state, the first antenna 101 and the second antenna 102 are switched. Thereby, appropriate antenna switching can be performed with a simple configuration.
[0054]
Further, by performing antenna switching within the set time of the out-of-service determination timer, a better antenna can be selected before the out-of-service determination is performed. If a signal having a level equal to or greater than the in-service area → out-of-service threshold L cannot be received within the set time of the out-of-service area determination timer, out-of-service determination is performed, and antenna switching is performed until the received signal level becomes out of the service area → in-service area threshold H. Therefore, unnecessary antenna switching operation can be reduced.
[0055]
Furthermore, since the antenna switching is performed within the out-of-range determination timer set time, even if the out-of-range condition is reached, the wireless communication device does not immediately transition to the out-of-range state, so the determination level of the received signal at this time is not out of range → in-range threshold H, The inside threshold → outside service threshold L may be used. In this case, since it becomes easier to shift to the normal standby state by the hysteresis HS = HL [dB] than the normal return to the service area, it is possible to shorten the out-of-service time and improve the reception rate.
[0056]
Furthermore, the communication state detecting unit 109 is provided, and the antenna switching is limited to the non-communication state (waiting). In addition, since the out-of-service level is set as the threshold in the first place, if the reception is normally performed, the antenna is not switched, so that the antenna is not switched despite the reception being successful, and the threshold is also variable. Therefore, the processing is not complicated and the efficiency is high.
[0057]
In addition, even when the wireless communication apparatus is a CDMA mobile phone that performs a continuous wireless communication operation, if a configuration in which antenna switching is performed according to out-of-service conditions and duration as in the present embodiment is used, a reception circuit (RF Unit 104, modulation / demodulation unit 105, etc.) is sufficient. Therefore, as compared with a case where two or more receiving circuits are provided and antenna diversity is performed, there is no increase in circuit scale, and antenna switching can be realized with a simple configuration. Further, complicated processing in the control unit is not required.
[0058]
In addition, the received signal measuring unit 106 for measuring the received signal strength and signal quality is used for another function, so that the circuit can be shared and can be realized by software, so that an increase in circuit scale and current consumption can be suppressed. .
[0059]
(2nd Embodiment)
FIG. 4 is a block diagram illustrating a configuration of the wireless communication device according to the second embodiment of the present invention. In the second embodiment, an example of a wireless communication device including three antennas will be described.
[0060]
The second embodiment is an example in which, for example, when the wireless communication device is a mobile station device such as a mobile phone having a foldable housing, the antenna is switched to an antenna having good characteristics according to the state of the housing. It is.
[0061]
The wireless communication apparatus 200 according to the second embodiment further includes a third antenna 203, and a control unit 210 including an open / close detection unit 201 and an antenna switching condition storage unit 202. Other configurations are the same as those of the first embodiment shown in FIG. 1, and the same components as those of the first embodiment are denoted by the same reference numerals.
[0062]
The antenna switch 103 of the second embodiment switches between the first antenna 101, the second antenna 102, and the third antenna 203 according to a switching control signal from the antenna switching unit 111.
[0063]
The opening / closing detection unit 201 corresponds to an example of an opening / closing detection unit, and detects a housing opening / closing state of whether the housing of the wireless communication device 200 is open or closed. The antenna switching condition storage unit 202 corresponds to an example of an antenna switching condition storage unit, and determines an antenna switching condition corresponding to an open / closed state of the housing and a first antenna to be selected when the housing opening / closing operation is performed. Are stored to store the antenna switching conditions.
[0064]
FIG. 5 is a diagram illustrating an example of an antenna switching condition corresponding to the open / closed state of the housing. In this example, the first antenna 101 has good characteristics (antenna sensitivity, antenna efficiency, etc.) in both the open state and the closed state of the housing, and the second antenna 102 has good characteristics only when the housing is open. The characteristics of the three antennas 203 are improved only when the housing is closed. For this reason, in this embodiment, when the housing is open, the antennas to be switched are limited to the first antenna 101 and the second antenna 102, and when the housing is closed, the antennas to be switched are the first antennas. 101 and the third antenna 203.
[0065]
Next, the operation of wireless communication apparatus 200 configured as described above will be described. FIG. 6 is a flowchart illustrating the operation of the wireless communication device according to the second embodiment. The procedure of FIG. 6 is mainly executed by the control unit 210.
[0066]
In FIG. 6, the procedure from the detection of the received signal deterioration to the level determination, that is, the operations in steps S101 to S104 are the same as those in the first embodiment shown in FIG. If it is determined in step S104 that the vehicle is out of the service area, the open / close state of the housing is determined (step S201).
[0067]
If it is determined in step S201 that the housing is open, the antenna switching between the first antenna 101 and the second antenna 102 is performed in accordance with the antenna switching conditions stored in the antenna switching condition storage unit 202. Perform (Step S105). On the other hand, when it is determined in step S201 that the housing is closed, the antenna switching between the first antenna 101 and the third antenna 203 is performed in accordance with the antenna switching condition stored in the antenna switching condition storage unit 202. Switching is performed (step S202).
[0068]
When the antenna switching process is completed, the process proceeds to step S106, and it is determined whether or not the out-of-service area determination timer setting time remains. Subsequent processing is the same as in the first embodiment shown in FIG. Further, in step S104, the processing after the case where it is determined that the vehicle is within the service area is the same as that of the first embodiment shown in FIG.
[0069]
As described above, in the second embodiment, when the wireless communication device has a foldable housing or the like, the switching antenna is limited and the antenna switching is performed according to the open / closed state of the housing. The antenna is switched so that only the antenna having good characteristics is used. That is, as shown in FIG. 3, when the reception signal falls below the out-of-service threshold L in the non-communication state as in FIG. As a result, every time it is determined that the received signal level is below the in-range to out-of-range threshold L, the first antenna 101, the second antenna 102, and the third antenna 203 perform antenna switching. At this time, in accordance with the open / close state of the housing, the antenna switching is performed by limiting the antennas to be switched to the first antenna 101 and the second antenna 102 or the first antenna 101 and the third antenna 203. The limitation of the switching antenna changes the selection state depending on the open / close state of the housing in accordance with the antenna switching condition stored in the antenna switching condition storage unit 202. This allows efficient antenna switching with a simple configuration.
[0070]
In addition, since the antenna that performs switching can be limited according to the open / closed state of the housing, for example, as shown in FIG. The antenna 102 has good characteristics only when the housing is in the open state, and the third antenna 203 has good characteristics only when the housing is in the closed state, and the third antenna 203 has poor characteristics when the housing is open. This prevents switching. In addition, when the housing is closed, switching to the second antenna 102 can be prevented. For this reason, if the antenna switching condition is appropriately set in the antenna switching condition storage unit 202, it is possible to limit the antennas for which antenna switching is performed according to the open / closed state of the housing, and thus to perform efficient antenna switching with a simple configuration. be able to.
[0071]
Further, the wireless communication device 200 of the present embodiment is configured such that an antenna to be selected first when an opening / closing operation of the housing is performed can be set in the antenna switching condition storage unit 202 in a non-communication state. For this reason, for example, when the housing is closed from the state where the housing is open and the second antenna 102 is selected, or when the housing is closed and the third antenna 203 is selected. For example, when the housing is opened from the state, the antenna is switched to the antenna in the initial selection state at the time of the opening / closing operation set in the antenna switching condition storage unit 202. Therefore, even when the wireless communication device 200 is opened / closed, the optimum antenna is opened. Can be selected.
[0072]
(Third embodiment)
FIG. 7 is a block diagram illustrating a configuration of a wireless communication device according to the third embodiment of the present invention. In the third embodiment, an example of a wireless communication device including two antennas will be described.
[0073]
In the third embodiment, for example, when the wireless communication device is a mobile station device such as a mobile phone having a foldable housing, an antenna having good characteristics is forcibly provided according to the communication state of the wireless communication device. This is an example in which antenna switching is performed.
[0074]
The wireless communication apparatus 300 according to the third embodiment has a control unit 310 provided with an open / close detection unit 201. Other configurations are the same as those of the first embodiment shown in FIG. 1, and the same components as those of the first embodiment are denoted by the same reference numerals.
[0075]
The antenna switching unit 111 always selects the first antenna 101 when the wireless communication device 300 is in the communication state, and always switches the antenna selection state to the second antenna when the housing is opened and closed when the wireless communication device 300 is in the non-communication state. A control signal is sent to the antenna switch 103 so as to select the antenna 102, and the selection state of the antenna is switched.
[0076]
Next, the operation of wireless communication apparatus 300 configured as described above will be described. FIG. 8 is a flowchart illustrating the operation of the wireless communication device according to the third embodiment. The procedure in FIG. 8 is mainly executed by the control unit 310.
[0077]
First, the opening / closing detection unit 201 detects whether the housing of the wireless communication device 300 is open / closed, and determines whether the housing has been opened (step S301). When it is determined in step S301 that the housing is closed, the antenna is forcibly switched to the second antenna 102 for the non-communication state (step S304). Then, the process ends.
[0078]
On the other hand, if it is determined in step S301 that the housing is open, the communication state detection unit 109 determines whether the wireless communication device 300 is in a communication state or a non-communication state (step S302).
[0079]
If it is determined in step S302 that the wireless communication apparatus 300 is in the communication state, the antenna is forcibly switched to the first antenna 101 for the communication state (step S303). When it is determined in step S302 that the wireless communication apparatus 300 is in the non-communication state, the antenna is forcibly switched to the second antenna 102 for the non-communication state (step S304).
[0080]
As described above, in the third embodiment, when the wireless communication device has a foldable housing or the like, the antenna is forcibly switched to an antenna having good characteristics according to the communication state of the wireless communication device. As a result, in both the communication state and the non-communication state (waiting), it is possible to receive with an antenna having good characteristics.
[0081]
In the case of a wireless communication device having a collapsible housing, it is often used with the housing open in a communication state. Here, the first antenna 101 has good characteristics in a state in which the user holds the hand with the housing open and talks near the head (communication state), and the second antenna 102 in other usage forms. Are better in characteristics. In such a case, the first antenna 101 is selected to be used in the communication state, and the second antenna 102 is selected in the non-communication state regardless of the open / closed state of the housing. Thereby, in a state where the user holds the hand with the housing open and talks with the user close to the head (communication state), the user can always select to use the first antenna 101 suitable for the communication state, and can stably operate. The received signal level can be received.
[0082]
Further, in the non-communication state, each time the housing of the wireless communication device is opened and closed, the antenna selection state can be returned to the second antenna 102 suitable for the non-communication state. If the case is closed even in the communication state, the communication ends and the state shifts to the non-communication state. Therefore, if the housing is closed in the communication state, it is not determined whether or not the communication state is established in step S302. Since the antenna can be immediately returned to the antenna suitable for the non-communication state, the operation procedure can be further simplified.
[0083]
Further, when the antenna switching described in the first embodiment is performed in a non-communication state, the housing is opened even when the first antenna 101 is selected and a sufficient reception signal is obtained. The second antenna 102 has better characteristics than the first antenna 101 except for a usage mode in which the user holds the hand in close proximity to the head. In this case, when the level changes next, the reception signal level is likely to be out of service condition when the first antenna 101 is selected. For this reason, when the housing of the wireless communication device is opened and closed and the open / closed state of the housing changes, the second antenna 102 is less affected by a change in the received signal level and is more effective. When the housing is opened and closed, the antenna selection state is initialized so as to start from the selection of the second antenna 102 as an initial state. As a result, the shortening of the out-of-service time and the unnecessary antenna switching are reduced, so that the out-of-service time can be reduced and the call connection rate can be improved.
[0084]
Further, when the housing is closed even in the communication state, the wireless communication apparatus is in a state where the communication has been completed or has been separated from the user's head. Therefore, it is preferable to select the second antenna 102 suitable for the non-communication state. Is effective. This can further shorten the out-of-service time and improve the call connection rate.
[0085]
(Fourth embodiment)
FIG. 9 is a block diagram illustrating a configuration of a wireless communication device according to the fourth embodiment of the present invention. In the fourth embodiment, an example of a wireless communication device including two antennas will be described.
[0086]
The fourth embodiment is an example in which antenna switching is performed when a suitable antenna is provided in a non-communication state, in a call connection process in a communication state, and in a normal communication state.
[0087]
The wireless communication apparatus 400 according to the fourth embodiment has a control unit 410 provided with a call connection state detection unit 401. Other configurations are the same as those of the first embodiment shown in FIG. 1, and the same components as those of the first embodiment are denoted by the same reference numerals.
[0088]
The operating state of the wireless communication device 400 includes a communication state and a non-communication state. The communication state includes a state in which the call connection processing is being performed and a normal communication state in which the call connection processing is completed and the call connection is established. The call connection state detection unit 401 corresponds to an example of a call connection state detection unit, and determines whether the wireless communication apparatus 400 is in a communication state and is in a call connection process or after a call connection is established.
[0089]
Here, one of the two antennas, the first antenna 101 and the second antenna 102, of the wireless communication device 400 is an antenna suitable for a normal communication state, and the other is an antenna suitable for a non-communication state and a communication state. It is assumed that the antenna is suitable for call connection processing.
[0090]
As described above, when the communication state detecting unit 109 detects the non-communication state when an antenna suitable for each state is provided, an antenna suitable for the call connection processing in the non-communication state and the communication state is included in the first embodiment. It is selected by the antenna switching shown. On the other hand, when detecting the communication state, the call connection state detection unit 401 determines whether the call connection processing is being performed or after the call connection is established, and during the call connection processing, is suitable for the call connection processing in the non-communication state and the communication state. The call connection processing is performed by switching to use the antenna that has been used, and after the call connection processing is completed and the call connection is established, the antenna is switched to an antenna suitable for the normal communication state.
[0091]
Next, the operation of wireless communication apparatus 400 configured as described above will be described. FIG. 10 is a flowchart illustrating the operation of the wireless communication device according to the fourth embodiment. Note that the procedure of FIG. 10 is mainly executed by the control unit 410.
[0092]
First, the communication state detection unit 109 detects the communication state of the wireless communication device 400, and determines whether or not the wireless communication apparatus 400 is in the communication state (step S401).
[0093]
When it is determined in step 401 that the communication state is established, the call connection state detection unit 401 determines whether the call connection is being processed or after the call connection is established (step S402). If it is determined in step S402 that the call connection process has been completed and the call connection has been established, the mobile terminal switches to an antenna suitable for the normal communication state to shift to a normal communication state (step S403). Then, the process ends.
[0094]
On the other hand, if it is determined in step S401 that it is not in a communication state, that is, it is in a non-communication state, or if it is determined in step S402 that it is in a call connection process, the call connection processing in the non-communication state and the communication state is started. Switching to a suitable antenna (step S404).
[0095]
For example, in the case of an incoming call in which a connection request is made from the base station, call connection is performed until the user of the wireless communication device presses the talk button, or until the user presses the talk button and the ringing tone ends. Processing is in progress. Also, in the case of a call, the call connection process is performed until the user presses the call button and the ringing tone of the other party sounds. In such a case, the state in which the user uses the wireless communication device with the hand held close to the head is after the above-described call connection processing has been completed, and during the call connection processing, the user's pants or shirt pocket. It is conceivable that the wireless communication device is located inside a bag, in a bag, on a desk, on a charging stand, or in a state where the wireless communication device is held in the user's hand but not close to the head.
[0096]
Therefore, in the present embodiment, the currently selected antenna is held until the call connection processing is completed, and the call connection processing is completed and the call connection is established. Switch to an antenna suitable for the communication state. Thus, it is possible to select an optimum antenna in each of the non-communication state (waiting), the call connection processing in the communication state, and the normal communication state after the call connection is established.
[0097]
As described above, in the fourth embodiment, the optimum antenna is selected in each operation state by switching to an appropriate antenna in each of the call connection processing in the non-communication state and the communication state and the normal communication state. It is possible to stabilize the call connection systematically.
[0098]
According to the above-described embodiment, antenna switching can be realized with a simple configuration without increasing the circuit scale. In addition, antenna diversity can be applied to a CDMA wireless communication device in which communication operation is continuous. Furthermore, when the wireless communication device is present in the weak electric field region in the non-communication state (waiting), it is possible to select an antenna which has good characteristics and does not reach the out-of-service level, thereby shortening the out-of-service time and reducing the call connection rate. Improvement can be achieved. Also, in the communication state, the currently selected antenna is maintained during the call connection process, communication is established after the call connection process is completed, and after transition to the normal communication state, an antenna suitable for the normal communication state is set. By enabling such selection control, call connection can be stabilized.
[0099]
【The invention's effect】
As described above, according to the present invention, it is possible to cope with a wireless communication system that performs a continuous reception operation, realize a proper antenna switching with a simple configuration without increasing the circuit scale, and A wireless communication device and an antenna switching method capable of shortening time and improving a call connection rate can be provided.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a wireless communication device according to a first embodiment of the present invention.
FIG. 2 is a flowchart showing the operation of the wireless communication device according to the first embodiment;
FIG. 3 is a state transition diagram showing the operation of the wireless communication device according to the first embodiment.
FIG. 4 is a block diagram showing a configuration of a wireless communication device according to a second embodiment of the present invention.
FIG. 5 is a diagram illustrating an example of an antenna switching condition corresponding to an open / closed state of a housing;
FIG. 6 is a flowchart illustrating the operation of the wireless communication apparatus according to the second embodiment;
FIG. 7 is a block diagram showing a configuration of a wireless communication device according to a third embodiment of the present invention.
FIG. 8 is a flowchart showing the operation of the wireless communication device according to the third embodiment;
FIG. 9 is a block diagram showing a configuration of a wireless communication device according to a fourth embodiment of the present invention.
FIG. 10 is a flowchart illustrating the operation of the wireless communication apparatus according to the fourth embodiment;
[Explanation of symbols]
100, 200, 300, 400 wireless communication device
101 First antenna
102 Second antenna
103 antenna switch
104 RF section
105 Modulator / demodulator
106 Received signal measurement unit
107 Out of service area judgment unit
108 Out of service timer
109 Communication state detector
110, 210, 310, 410 control unit
111 Antenna switching unit
201 Open / close detector
203 Third antenna
202 Antenna switching condition storage unit
401 call connection state detection unit

Claims (5)

A wireless communication device having a plurality of antennas,
Antenna switching means for switching the plurality of antennas,
Received signal measuring means for measuring a received signal level received by any one of the plurality of antennas,
Out-of-service determining means for determining whether or not out of the communication range according to the measurement result of the received signal measuring means,
If the out-of-service determination unit determines that the received signal level has reached the out-of-service condition, an out-of-service determination timing unit that counts the duration of the out-of-service condition,
Communication state detection means for detecting the communication state of the wireless communication device;
When the wireless communication device is determined to be in a non-communication state by the communication state detection means, and when the out-of-service determination time determination means is determined to have reached the out-of-service condition by the out-of-service determination means, a predetermined Within the timed set time, each time it is determined that the out-of-service condition has been reached by measuring the received signal level at predetermined intervals, antenna switching control means for switching the plurality of antennas,
A wireless communication device comprising: The wireless communication device according to claim 1,
It is configured with a foldable housing,
Opening and closing detection means for detecting opening and closing of the housing;
Antenna switching condition storage means for storing antenna switching conditions corresponding to the open and closed state of the housing,
The wireless communication device, wherein the antenna switching control unit is configured to limit an antenna to be switched in each of a state where the housing is open and a state where the housing is closed, according to the antenna switching condition. The wireless communication device according to claim 1,
It is configured with a foldable housing,
An opening / closing detecting means for detecting opening / closing of the housing,
The antenna switching control unit, when the opening / closing of the casing is detected by the opening / closing detection unit, is suitable for a communication state when the wireless communication device is in a communication state based on a detection result of the communication state detection unit. A wireless communication apparatus for selecting an antenna and selecting an antenna suitable for the non-communication state every time the housing is detected to be open or closed in the non-communication state. The wireless communication device according to claim 1,
Comprising a call connection state detecting means for detecting a call connection state of the wireless communication device,
The antenna switching control means, based on the detection result of the call connection state detection means, holds the current antenna connection when the wireless communication device is in a communication state and is performing a call connection process, and terminates the call when the call connection process ends. A wireless communication device that performs antenna switching suitable for the actual use state after connection establishment. An antenna switching method in a wireless communication device having a plurality of antennas,
A communication state detection step of detecting a communication state of the wireless communication device;
An out-of-range determination step of measuring a received signal level received by any one of the plurality of antennas and determining whether or not it is out of the communication range,
When the non-communication state is detected in the communication state detection step, and when it is determined in the out-of-service determination step that the reception signal level has reached the out-of-service condition, the out-of-service area that measures the duration of the out-of-service condition has been reached. A timekeeping step,
An antenna that switches the plurality of antennas each time the reception signal level is measured at a predetermined interval and it is determined that the out-of-service condition has been reached within a predetermined time setting time after the start of time measurement of the out-of-service condition. A switching control step;
An antenna switching method comprising:

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