JP2007158530A - Antenna switching method of mobile communication terminal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mobile communication terminal for utilizing two kinds of frequency bands and including four antennas, two of which can utilize one kind of frequency band and the other two of which can utilize the other kind of the frequency band that partly modifies a program and uses the partly modified program so as to prevent switch-over mistakes from taking place among the antennas, when one of the antennas is reduced for the purpose of reducing the mounting area. <P>SOLUTION: When the antennas are switched-over, the output contents of an antenna selection signal for designating switch-over destination are changed depending on the antennas of the switch-over source and the switch-over destination. Thus, the mobile communication terminal can cope with the reduction with only one antenna, by partly modifying the program for a control means for controlling the revision and installation of a logic gate so as to eliminate the need for a large scale in design change. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a mobile communication terminal that has a plurality of types of transmission / reception frequency bands and enables efficient diversity reception in each frequency band.

  As the number of terminals used increases, the frequency band used by mobile communication terminals also increases, and in order to avoid congestion of communication traffic, mobile communication terminals that can use multiple frequency bands within the same mobile communication terminal have appeared.

  Further, in order to cope with a decrease in antenna sensitivity due to terminal holding, there is a space diversity in which a plurality of antennas are provided at different locations in the mobile communication terminal, so that the antenna used is switched when the antenna sensitivity decreases.

  In the case of data transmission for receiving radio signals modulated to a plurality of conventional frequencies, first compare the reception levels of the receivers connected to all the antennas, select the receiver with the highest reception level, A configuration is known in which a receiver having a high reception level is selected from the receivers having the same reception frequency as that receiver (Japanese Patent Laid-Open No. 9-307490).

  Note that Patent Document 1 in which this configuration is disclosed includes reception using two frequencies as a mobile communication terminal using a plurality of frequencies and having a receiver installed at a different position for each frequency. Two mobile devices are provided, and the mobile communication terminal has a total of four receivers.

  Similarly, in a mobile communication terminal using a plurality of frequency bands in common, for example, the 800 MHz band and the 1.5 GHz band, the mobile communication terminal having a total of three antennas using each frequency band has different positions. According to the antenna characteristics of the antennas arranged in the antenna, each dedicated transmission / reception antenna is provided, and when the frequency is changed, each transmission / reception antenna and reception dedicated antenna are assigned among the three antennas. A configuration for switching is known (Japanese Patent Application Laid-Open No. 2004-104184).

Japanese Patent Laid-Open No. 9-307490 JP 2004-104184 A

  However, in the case of a mobile communication terminal having four receivers of Patent Document 1, as the types of frequencies to be used increase, the number of receivers corresponding thereto increases, leading to an increase in the mounting area of the terminal.

  Further, the antenna switching method of Patent Document 2 is a specification when the antenna switching circuit itself for switching antennas has three antennas.

  For this reason, it is impossible to divert components such as an antenna switching circuit created for a mobile communication terminal having the original four antennas as standardized components. Therefore, compared with the case of diverting the parts of the mobile communication terminal having four antennas, time and cost for developing the parts for the mobile communication terminal having three antennas are generated.

  In the present invention, two receiving antennas for two or more frequency bands are mounted for each frequency band, and an antenna capable of obtaining a good reception level is selected under a situation where the original antenna characteristics cannot be exhibited due to the influence of hand-holding or the like. By reducing the number of antennas for mobile communication terminals that have a radio control unit and antenna unit designed to improve the communication maintenance rate, we will try to reduce the size of mobile communication terminals and maintain good communication conditions. It is what.

  In a mobile communication terminal having a specification with one antenna for one frequency, if an antenna switching method using the same circuit as a mobile communication terminal having four antennas is used, communication may be disabled.

  Here, the present invention is an antenna switching method in a mobile communication terminal having three antennas as described above, and the mobile communication terminal having the above three antennas is changed by changing the software logic with respect to the conventional antenna switching method. Provides a configuration that enables avoidance of an unusable state.

  That is, in the antenna switching method in the mobile communication terminal of the present invention, in the mobile communication terminal designed to control the frequency designation by software based on the timing determined by the hardware, one frequency band is used to reduce the mounting area. There is provided a method for selecting an antenna having a good reception level when the number of antennas is reduced by using two antennas for the frequency band and one antenna for the other frequency band.

  The effect of the present invention is not limited to reducing the antenna mounting area in the mobile communication terminal by reducing the number of antennas.

  For the antenna switching method developed for mobile communication terminals with two antennas for two frequency bands, only the software logic is changed corresponding to the case where the number of antennas is reduced to reduce the mounting area of the terminal This is a possible point.

  In other words, according to the antenna switching method for a terminal with the reduced number of antennas according to the present invention, a part of the hardware of a mobile communication terminal having two antennas for two frequency bands is changed and developed for the terminal. Since the antenna switching method is made compatible only by changing the software logic, the device specification as a conventional mobile communication terminal can be easily diverted without greatly changing.

  A configuration of a mobile communication terminal according to an embodiment of the present invention will be described in detail with reference to the drawings.

  Here, in the mobile communication terminal of the embodiment of the present invention, one antenna using one frequency band is subtracted from the conventional mobile communication terminal having two antennas for two frequency bands, and the logic gate is passed. An antenna switching method in which software logic is changed in correspondence with the antenna designation signal, and a mobile communication terminal capable of executing this antenna switching method.

  For this reason, mounting components common to the mobile communication terminal using the antenna switching method of the present invention are used, and the original mobile communication terminal having two antennas for two frequency bands (hereinafter referred to as the conventional terminal 2) is used. And the antenna switching method in the mobile communication terminal.

  Further, a mobile communication terminal capable of implementing the antenna switching method of the present invention is referred to as an antenna processing terminal 1 in order to clarify the difference from the conventional terminal 2 as a prototype.

  The frequency bands that can be used by the antenna processing terminal 1 and the conventional terminal 2 are, for example, the 1.5 GHz band and the 800 MHz band. Here, these two types of frequency bands are A and B.

  X and Y of the antenna for each frequency band of frequency band A and frequency band B are mounted at different positions on the mounting of the terminal.

  This is an arrangement by different antenna positions where a good reception level can be obtained depending on the portion held by the user when holding the terminal.

  For this reason, for example, even when one antenna is covered by gripping, reception by the other antenna reduces the effect of being covered by the hand, and an antenna having a good reception level can be selected.

  Here, as shown in FIG. 1, both the conventional terminal 2 and the antenna processing terminal 1 are described assuming that the antenna X is provided at or near the hinge portion 3 of the folding housing, and the antenna Y is provided at the lower portion 4 of one housing. To proceed.

  In order to receive a radio signal in a different frequency band and measure the reception level in that frequency band in the conventional terminal 2 in the communication state, measure the timing on the radio line, and the conventional terminal 2 of its own station transmits and receives communication data It is necessary to finish the measurement in a short time at a timing that is not performed.

  In addition, since the frequency band is specified by software, the timing control for switching the antenna should be realized by a functional block shown in the frequency band specifying unit 230 of FIG. Is required.

  FIG. 2 is a block diagram of the antenna configuration of the conventional terminal 2 including the frequency band specifying unit 230 that generates the frequency band specifying signal.

  The conventional terminal 1 has a CPU 100 that operates under program control, a radio control LSI 200 that performs radio-related control, modulation, and demodulation of the conventional terminal 1, an antenna selection signal and a frequency band designation signal that are determined, It includes an antenna switching LSI 300 that connects a transceiver, an antenna unit 400 that receives radio waves in a plurality of frequency bands, and a memory 600 that stores measurement data of reception levels of currently used antennas.

  The CPU 100 measures the reception level of the currently used antenna, stores the measurement data in the memory 600, and compares the reception level of the antenna used before and after the antenna switching.

  Then, a good antenna is determined, and an antenna selection signal indicating this antenna is output.

  Further, the radio control unit LSI 200 receives a frequency band A TRX unit (Transmitter & Receiver, hereinafter referred to as a TRX unit) 210 and a frequency band B TRX unit 220, and frequency band parameters and timing given from the CPU 100. The frequency band specifying unit 230 generates a frequency band specifying signal to be input to the antenna switching unit LSI 300 according to the timing.

  Here, since the TRX unit 210 performs processing in the frequency band A, the transmitter TX unit (Transmitter) 211 for transmission signal control, the reception unit RX unit (Receiver) 212 for reception signal control, the transmission and reception signals This is a transmission / reception unit including a duplex communication unit (Duplexer) 213 that separates and couples.

  Similarly to the TRX unit 210, the TRX unit 220 performs processing of the frequency band B, and transmits a transmitter TX unit (Transmitter) 221 for controlling transmission signals, a receiving unit RX unit (Receiver) 222 for controlling received signals, This is a transmission / reception unit including a duplex communication unit (Duplexer) 223 that separates and combines received signals.

  The antenna unit 400 includes four antennas each including two transmission / reception antennas that can use two frequency bands A and B.

  The specific antenna for each frequency band is the antenna X corresponding to the frequency band A, the antenna 411, the antenna Y corresponding to the antenna 412, the antenna X corresponding to the frequency band B corresponding to the antenna 421, and the antenna Y corresponding to the antenna 422. .

  However, when a specific antenna is selected, for example, when the antenna X of the frequency band A is selected, it is described as an antenna (A, X) 411.

  The memory 600 connected to the CPU 100 includes a program of functions common to the antenna processing terminal 1 and the conventional terminal 2, information for a telephone directory that stores a telephone number, and the like of each antenna at the time of antenna switching. Holds the reception level data.

  Next, the antenna switching LSI 300 for switching antennas will be described.

  FIG. 3 is a diagram illustrating an antenna selection signal input to the antenna switching LSI 300 and a selection state of the antenna unit 400, the TRX unit 210, and the TRX unit 220 for each antenna selection signal.

  The antenna selection signal is generated by the CPU 100, and the signal specifying the antenna X is indicated by the antenna selection signal x. When this signal is inverted by the CPU 100, the antenna selection signal y specifying the antenna Y becomes the antenna selection signal. The LSI 300 designates an antenna at a predetermined position by these signals.

  The frequency band specifying unit 230 in the radio control LSI 200 generates a frequency band specifying signal based on the timing and frequency parameters given from the CPU 100, and the signal specifying the frequency band A is indicated by the frequency band specifying signal a. . Further, when this signal is inverted by the frequency band specifying unit 230, the frequency band specifying signal b for specifying the frequency band B is obtained, and a predetermined frequency band is specified by these signals.

  The antenna switching LSI 300 creates four states based on these two-input antenna selection signals and the frequency band designation signal, and the antenna switching LSI 300 receives the antennas (411, 412) in the antenna unit 400 that receive from time to time based on these signals. 421, 422) and the TRX units 210 and 220 for the radio frequency band A and the radio frequency band B in the radio control unit 200 are selected and connected.

  Thus, four types of antenna unit-TRX unit connection states are generated by the combination of inversion of the input signal.

  For example, when the antenna X of the frequency band A is selected, that is, when the antenna (A, X) 411 is selected, when the two signals of the frequency band designation signal a and the antenna selection signal x are input to the antenna switching LSI 300, The antenna switching LSI 300 connects the antenna (A, X) 411 and the TRX unit 210.

  Thereby, the antenna switching LSI 300 performs antenna switching during communication by combining the antenna switching by the antenna selection signal and the frequency band designation by the frequency band designation signal.

  The antenna switching method of the conventional terminal 2 by the antenna designation is as follows. First, the radio control unit LSI 200 measures the reception level of those antennas for the currently selected one frequency band, the CPU 100 compares the measurement results, The antenna switching method selects an antenna having a better reception level among antennas using a frequency band. This antenna switching method is referred to as a conventional terminal antenna switching method.

  In other words, when checking the reception level for each frequency band described above, there is no need to be aware of which antenna X or antenna Y is selected, and the two are switched only by the respective reception levels.

  FIG. 4 shows the software control by the CPU 100 when the conventional terminal antenna switching is performed.

  First, an antenna switching condition for changing the antenna is established between antennas using the same frequency band. (Step 41). Here, the fact that the antenna switching condition is satisfied is a state in which the antenna can be changed by transitioning to an antenna selection state, and the antenna is not necessarily switched.

  Further, the case where the antenna switching condition is satisfied is a condition designed for each device characteristic and design thinking, for example, when communication starts and ends, or when synchronization with the base station is out of sync.

  Thereafter, the CPU 100 performs the first measurement of the reception level of the frequency band using the currently selected antenna (step 42), and holds the measurement result on the memory 600.

  After holding the measurement result, the CPU 100 inverts the logic of the antenna selection signal (step 43) to switch the antenna, and the CPU 100 performs the second reception level measurement again (step 44). The result is held on the memory 600.

  The CPU 100 compares the measurement result of the first time with the measurement result of the second time (step 45), and compares and determines whether any measurement result is good.

  Here, when the reception level of the second measurement data measured with the antenna switched by inverting the antenna selection signal is higher than the first measurement data which is the measurement data of the antenna originally used, The CPU 100 does not switch the antenna switching LSI 300 using the antenna selection signal. That is, the antenna used in the second measurement is used without switching the antenna. As a result, the antenna that was originally used can be switched.

  Conversely, if the first measurement data has a better reception level, the CPU 100 again switches the antenna used when measuring the first measurement data by inverting the logic of the antenna selection signal. Use (step 46). As a result, communication is continued with the antenna originally used. As a result, the antenna with the higher reception level in the frequency band can be selected, and a good reception level is ensured.

FIG. 5 is a sequence diagram showing an operation example in this conventional terminal antenna switching.
T1 to T9 in FIG. 5 are numbers indicating antenna switching timing.

  In addition, the black and white band in the upper part of FIG. 5 is the frequency band being used, the shaded portion is a period in which communication is performed in the frequency band A, and the white portion is a period in which communication is performed in the frequency band B.

  After the start of communication, the antenna processing terminal 1 first performs communication with the antenna (B, X) 421 in the frequency band B (T1).

  The antenna switching condition is satisfied, and the CPU 100 outputs the antenna selection signal y, thereby switching the antenna from the antenna (B, X) 421 to the antenna (B, Y) 422 (T2).

  During communication in the frequency band B using the antenna (B, Y) 422, in order to monitor the reception level of the frequency band A, the antenna frequency band specifying unit 230 performs logic inversion to the frequency band specifying signal a. The antenna 100 is changed to the antenna (A, Y) 412, and the CPU 100 measures the reception level of this antenna (T3). After the CPU 100 measures the reception level of the frequency band A, the measurement data is held in the memory 600, and then the antenna frequency band designation unit 230 logically inverts the frequency band designation signal b to return to the frequency band B (T4). ), Communication is continued in the frequency band B with the antenna (B, Y) 422. (T4-T5). At this time, if the CPU 100 compares the data held in the memory 600 and determines that the reception level of the frequency band A measured between T3 and T4 is better than that of the frequency band B, the CPU 100 determines that the antenna selection signal a By reversing, the state transits to the communication state in the frequency band A, and communication is performed using the antenna (A, Y) 412 (T5).

  However, this frequency band change is generally performed in the conventional terminal 2 by normal network designation.

  Thereafter, while using the same frequency band, the antenna switching condition is satisfied, and the communication state using the antenna (A, X) 411 is changed (T6).

  This time, in order to monitor the state of the frequency band B, from the frequency band designation signal b logically inverted by the frequency band designation unit 230, the antennas (B, B) in the same installation location as the antenna (A, X) 411 are used. X) 421, and the CPU 100 performs reception level measurement (T7 to T8).

  After the measurement, the CPU 100 determines that the reception level of the frequency band A is in a better state, so the communication state with the antenna (A, X) 411 of the frequency band A is maintained (T8 to T9).

  Thereafter, the antenna switching condition is satisfied again, and the antenna (A, X) 411 is changed to the antenna (A, Y) 412 from the inverted antenna selection signal y (T9).

  Thus, the antenna switching by the antenna selection signal and the change of the frequency band by the frequency band designation signal are performed to maintain a good communication state.

  Also, as described above, the antenna switching and the frequency band change are performed asynchronously, so basically, when changing the frequency to the frequencies B and A for monitoring the status during communication in the frequency bands A and B, the antennas X and Y are State monitoring is performed without any particular change.

  Here, an embodiment of the mobile communication terminal of the present invention will be described.

  In the embodiment of the mobile communication terminal using the antenna switching method of the present invention, an antenna processing terminal 1 in which the frequency band B antenna Y cannot be mounted is assumed. FIG. 6 is a block diagram clearly showing the hardware change of the terminal.

  Since the antenna processing terminal 1 has a configuration that uses the configuration of the conventional terminal 2 of FIG. 2 as it is, the difference in the mounted parts is the same except for the addition of the logic gate 500 and the deletion of the antenna Y for the frequency band B.

  That is, the antenna unit 400 corresponds to only three antennas: an antenna 411 that is the antenna X corresponding to the frequency band A, an antenna 412 that is the antenna Y, and an antenna 421 that is the antenna X corresponding to the frequency band B.

  The functions of the radio control LSI 200 and the frequency band designating unit 230 in the radio control LSI 200 are the same as those of the conventional terminal 2 and the antenna processing terminal 1, and components of the conventional terminal 2 can be used.

  Therefore, when the antenna switching control is performed, the antenna processing terminal 1 having three antennas adds a logic gate 500 as hardware other than the radio control LSI 200 to provide an antenna to the antenna Y with the frequency band B reduced. The specification for each terminal is changed by changing the selection signal y to x.

  FIG. 7 is a diagram showing a logic table of the antenna selection LSI 300 and the logic gate 500 described above. The logic gate 500 is configured by a simple AND or OR gate or the like.

  By this logic gate 500, when the output content of the frequency band specifying unit 230 is the frequency band specifying signal b, the antenna X is selected regardless of the output content of the antenna selection signal from the CPU 100. With this change, the logic gate output state with respect to the input terminal state of the antenna switching LSI 300 of FIG. 7 is changed from the antenna switching LSI truth table of the conventional terminal 2 of FIG. 3, but the antenna switching LSI 300 itself is diverted. The function is not changed in both FIG. 6 and FIG. Therefore, when the frequency band designation signal b for designating the frequency band B first and the output content of the CPU 100 are the antenna selection signal y, that is, the input terminal state for designating the antenna (B, Y) 422, the logic gate 500 Thus, the gate output signal is changed to the antenna selection signal x, and the selected antenna 430 is the antenna (B, X) 421.

  Here, in the antenna processing terminal 1 in which the antenna Y of the frequency band B is not installed, the logic gate 500 is simply used without using the antenna processing terminal antenna switching method executed by changing the software logic that is a feature of the present invention. A conventional terminal antenna switching method that is supported by changing the output signal with only the following will be described.

  Even when the antenna switching process is performed using the conventional antenna switching method for a terminal, since the logic gate 500 exists, the signal y designating the antenna (B, Y) 422 is transmitted by the logic gate 500 as shown in FIG. Inverted and changed to an antenna selection signal x designating antenna (B, X) 421.

  However, when the conventional terminal antenna switching method is used in which only the logic gate 500 is provided and the software logic is not changed, and the conventional terminal antenna switching is performed according to the antenna switching operation example of FIG. It may become.

  FIG. 8 shows the state transition of antenna switching of the antenna processing terminal 1 when using the conventional terminal antenna switching method of FIG.

  After the start of communication, communication is first performed using the antenna (B, X) 421 in the frequency band B (T1).

  When the antenna switching condition is satisfied and the antenna to be used thereafter is recognized as the antenna (B, Y) 422, the CPU 100 changes the antenna from (B, X) 421 to (B, Y) 422. Then, an antenna selection signal y instructing switching is generated (T2).

  However, the antenna selection signal y is inverted by the logic gate 500 installed in the antenna processing terminal 1 to the antenna selection signal x for selecting (B, X) 421 instead of the antenna (B, Y) 422.

  While communicating with the antenna (B, X) 421 (T2 to T3), the CPU 100 measures the current reception level of the antenna (B, X) 421 and holds the measurement data in the memory 600, and then the frequency. The band designation unit 230 selects the antenna (A, Y) by inverting the frequency band designation signal a in order to monitor the reception level of the frequency band A (T3).

  However, from T2 to T3, the antenna actually used is (B, X) 421 for the reason described above, but the content of the signal output from the CPU 100 remains the antenna selection signal y. The CPU 100 recognizes that the antenna currently in use is the antenna (B, Y) 422.

  For this reason, when the CPU 100 checks the reception level of the frequency band A, the antenna (B, Y) 422 recognized as being used and the antenna (A, Y) 412 provided at the same place are used. It will be selected (T3).

  Therefore, when the reception level of the antenna (A, Y) 412 in the frequency band A is measured by the instruction of the CPU 100 and the measurement data is held in the memory 600 and then returned to the frequency band B again, the CPU 100 A, Y) 412 is determined to be selected on the same side as antenna (B, Y) 422. Therefore, frequency band specifying unit 230 outputs frequency band specifying signal b, and CPU 100 outputs antenna selection signal y. To do. However, at this time, since the antenna selection signal y is changed to the antenna selection signal x by the logic gate 500, the actual antenna used is not the antenna (B, Y) but the antenna (B, X) 421. (T4-T5).

  As shown in the above-described flow, the content of the antenna selection signal a from the CPU 100 and the actual antenna used by adding the logic gate 500 are different from each other.

  In other words, since antennas X and Y are at different mounting positions on the device, reception radio wave interference due to the effect of being covered with hands to grip the terminal, etc., even though communication status is good with antenna X, the reception level on antenna Y side is good It can be impossible to guarantee.

  For example, in the case of frequency band transition from T2 to T4 in FIG. 8, the CPU 100 measures the reception level of the frequency band B with the antenna X and measures with the antenna Y in the frequency band A. When the reception level of the frequency band A is good, the antenna X is not obstructed by gripping. Therefore, although the communication state when the antenna (A, X) 411 is used is good, the antenna ( Since the reception level of (A, Y) 412 is measured, the CPU 100 may determine that the reception level of the frequency band A is bad and the communication state is not good.

  In this case, although the reception level of the actual frequency band A is good, the communication state transition to the frequency band A does not occur, and the frequency band B having a poor reception level is selected at T5 in FIG. In the worst case, communication cannot be maintained.

  Therefore, in order to prevent this misidentification, the communication state is improved by changing the antenna switching method of the antenna processing terminal 1 provided with the logic gate 500 by changing the software logic.

  That is, in the antenna switching method of the present invention, when it is determined that the communication is in the frequency band B, the antenna always selects the antenna X regardless of the frequency band.

  By changing the software logic, it is no longer necessary to use the antenna Y side of the frequency band A for which the reception level state cannot be guaranteed. When transitioning to the frequency band A as indicated by T3 and T4 in FIG. Use to measure.

  Thus, by setting the antenna to be selected to be X, the reception level can be ensured because the same installation location is being used in the frequency band B. By using the antenna X of the frequency band A at T3 and T4, it is possible to change the communication frequency band at T5 without erroneously determining the reception level of the frequency band A and frequency band B in the subsequent determination of the reception level. It becomes. As a result, it is possible to maintain communication in a good communication state.

  Thus, the antenna switching method is made to correspond to the antenna processing terminal 1 in which only the two parts of the installation of the logic gate 500 for reducing the number of antennas and changing the antenna selection signal are used by diverting the mounting components of the conventional terminal 2. Therefore, the software logic of the conventional terminal antenna switching method is changed in two places.

  The changes of the antenna switching method by changing the software logic of the present invention are as follows.

  The first change is that when the frequency band B is selected by the frequency band specifying unit 230 of the wireless control LSI 200, the antenna to be used is specified as (B, X). This is to limit the available antennas when changing the frequency band.

  The second change point is to use the antenna (A, X) 411 when changing to the frequency band A during communication in the frequency band B. This is an antenna (B, X) 421 that is selected by fixing the antenna X when the frequency band is B according to the logic gate output signal. Therefore, when the frequency band A is changed, the antenna (always on the same side) This is because it is necessary to recognize that (A, X) 411 is used.

  That is, as described above, the antenna switching and the frequency band change are performed asynchronously. Therefore, at the time of changing the frequency to the frequencies B and A for monitoring the state during communication in the frequency bands A and B, the antennas X and Y are This is because state monitoring is performed without any particular change.

  Hereinafter, an antenna switching method will be described.

  FIG. 9 is a flowchart showing control on software when performing antenna switching for an antenna processing terminal, whereas FIG.

  9 differs from FIG. 4 in that it is determined that the frequency band is B in S91a and that the antenna is fixed to the antenna X when the frequency band is B (S91b).

  First, an antenna switching condition for changing the antenna is established between antennas using the same frequency band (step 90). Satisfaction of the antenna switching condition is designed for each device characteristic and design thinking, for example, when communication starts and ends, or when synchronization with the base station is out of sync.

  Here, it is determined whether the frequency band of the currently selected antenna, which is a difference of the present invention, is B (step 91a).

  This determination is performed by recognizing the antenna frequency determined by the CPU 100. Therefore, although the determination is also performed in the conventional terminal 2, in the conventional terminal, the determination of the use frequency band is not directly related to the antenna switching, and therefore, it is not added to the flowchart in FIG.

  When the frequency band is B, the antenna (B, X) 421 is selected and communication is performed as shown in the first change point of the software logic (step 91b).

When the frequency band is A, the antenna switching is performed for the first time at the reception level of the frequency band using the antenna selected by the CPU 100 as in the case of the conventional terminal 2 (step 92), and the measurement result is stored in the memory. It is held on 600.
After holding the measurement result, the CPU 100 inverts the logic of the antenna selection signal (step 93), switches the antenna, performs the second reception level measurement (step 94), and holds the measurement result in the memory 600. To do.
Subsequently, the CPU 100 compares the first measurement result with the second measurement result (step 95), and determines whether any of the measurement results is satisfactory.

  Here, when the reception level of the second measurement data measured with the antenna switched by inverting the antenna selection signal is higher than the first measurement data which is the measurement data of the antenna originally used, The antenna is used as it is without changing the antenna used for the second measurement.

  Conversely, when the reception level of the first measurement data is better, the antenna selection signal is logically inverted again to switch to the antenna used when the first measurement data is measured (step 96). ). By this operation, the antenna having the higher reception level in the frequency band is selected to ensure a good reception level.

  Next, a state transition diagram in the antenna switching for the antenna processing terminal of the present invention is shown in FIG.

  Note that T1 to T9 in FIG. 10 are numbers indicating antenna switching timing.

  Here, the two locations of the software logic change in FIG. 5 and FIG. 10 showing the conventional terminal are the antennas when the antenna switching of T2 is performed when the frequency band B is selected with respect to the first change point. Corresponds to the point that only antenna X is selected, and corresponding to the second change point, when communicating in frequency band B from T3 to T4, only antenna X is used when measuring frequency band A. Indicated.

  First, after the start of communication, first, the antenna (B, X) 421 in the frequency band B is selected to perform communication (T1).

  At T2, the antenna switching condition is satisfied, but the result is that the frequency selection signal b and the antenna selection signal y specifying the antenna (B, Y) 422 are changed to the antenna selection signal x by the logic gate 500. Thus, the communication is continued with the antenna (B, X) 421 being maintained.

  In order to monitor the reception level of the frequency band A, the frequency band designating unit 230 outputs the frequency band designating signal a, thereby changing the frequency band to A and measuring with the antenna (A, X) 411. (T3). Thereafter, the communication returns to the frequency band B and communication is continued with the antenna (B, X) 421 (T4).

  Here, when the frequency band B is measured, the antenna (B, X) 421 is selected in the first change of software logic in the antenna processing terminal antenna switching method.

  Further, when the frequency band A is changed to T3 in FIG. 10, the antenna (A, X) 411 is selected in the second change point of the software logic.

  In accordance with this change, the CPU 100 measures the reception level of the antenna (A, X) 411 in the frequency band A, returns to the frequency band B (T4), and continues communication using the antenna (B, X) 421. (T4-T5).

  As a result of the reception level measurement, when the CPU 100 determines that the reception level of the antenna (A, X) 411 in the frequency band A measured between T3 and T4 is better than the antenna (B, X) 421 in the frequency band B Then, the frequency band designation unit 230 inverts the frequency band designation signal, transitions to a communication state using the antenna (A, X) 411 of the frequency band A, and maintains the communication state (T5).

  In the frequency band A, the antenna switching condition is satisfied. However, as a result of the antenna reception level measurement according to the flowchart of FIG. 9 described above, the reception level of the antenna X is good. ) 411 is selected and communication is continued (T6 to T7).

  However, the change of the frequency band is generally performed by the network designation in the antenna processing terminal 1.

  Next, in order to monitor the state of the frequency band B, the CPU 100 changes the antenna used from the antenna (A, X) 411 and measures the reception level of the antenna (B, X) 421 of the frequency band B ( T7).

  After the measurement, the CPU 100 determines that the reception level of the antenna (A, X) 411 in the frequency band A is in a good state, so the communication state is maintained using the antenna (A, X) 411 in the frequency band A. (T8 to T9).

  Thereafter, the antenna switching condition is satisfied again, the antenna (A, X) 411 is changed to the antenna (A, Y) 412, and communication in the frequency band A is continued (T9).

  In the case of the antenna processing terminal 1 using the two frequency bands of the present invention and having two antennas and one antenna using the respective frequency bands, the antenna processing antenna for performing antenna switching and changing the frequency band as described above A good communication state is maintained by using a switching method.

  Further, as in the conventional terminal 2 having four conventional antennas, the antenna switching and the frequency band change are performed asynchronously, so that the frequency bands B and B for monitoring the state in communication in the frequency bands A and B basically. When changing the frequency band to A, the antenna performs state monitoring without any particular change.

It is an example of the antenna arrangement | positioning in the terminal which has several antennas using several frequency bands. It is a block diagram of the circuit regarding the radio | wireless transmission / reception of the conventional terminal. It is an input-output truth table of the signal regarding designation | designated of the antenna which the conventional terminal has. It is a flowchart which shows the flow of the antenna switching for conventional terminals. It is a transition diagram which shows the transition state of the antenna in the conventional terminal using the antenna switching method for conventional terminals. It is a block diagram of the circuit regarding the radio | wireless transmission / reception of the antenna processing terminal of embodiment of this invention. It is an input-output truth value table regarding the designation | designated of the antenna which the antenna processing terminal of embodiment of this invention has. It is a transition diagram which shows the transition state of the antenna in the antenna processing terminal using the conventional antenna switching method for terminals. It is a flowchart which shows the flow of antenna switching for antenna processing terminals. It is a transition diagram which shows the transition state of the antenna in the antenna processing terminal using the antenna switching method for antenna processing terminals.

Explanation of symbols

100 CPU
200 Wireless control LSI
210 TRX unit 211 for frequency band A TX unit 212 for frequency band A RX unit 213 for frequency band A Duplexer for frequency band A
220 Frequency Band B TRX Unit 221 Frequency Band A TX Unit 222 Frequency Band A RX Unit 223 Frequency Band A Duplexer
230 Frequency Band Designation Unit 300 Antenna Switching LSI
400 Antenna part 411 Frequency band A antenna X
412 Frequency band A antenna Y
421 Frequency band B antenna X
422 Frequency band B antenna Y
500 logic gate 600 memory

Claims (17)

For the first and second antennas that can use one frequency band, and the third and fourth antennas that can use the other frequency band, the first and third antennas are in one place, When the antenna is switched between four antennas designed to be mounted at the other location of the fourth antenna, antenna control that can be switched between antennas installed in the same frequency band and at the same position In a mobile communication terminal including means,
First to third antennas;
A logic gate that inverts an instruction to select the fourth antenna of the antenna control means to an instruction not to select the antenna;
The switching means performs control to select a remaining antenna without selecting the fourth antenna when the antenna to be switched is the fourth antenna when switching the antenna being used. Mobile communication terminal. The mobile communication terminal is
It is performed by changing from an antenna selection signal that designates the currently selected antenna output from the antenna switching means to an antenna selection signal that designates the antenna corresponding to the antenna switching destination,
The mobile communication terminal according to claim 1, wherein an antenna selection signal designating the fourth antenna is changed to an antenna selection signal designating another remaining antenna by the control. The antenna selection signal is
Position specification signal to specify the position,
And a signal that designates an antenna to be selected from a combination of frequency band designation signals that designate frequency bands to be used.
The antenna selection signal for designating an absent antenna by the control designates a remaining antenna by changing one of the signals, according to any one of claims 1 to 2. Mobile communication terminals. 4. When switching a frequency band, when switching from the second antenna to the fourth antenna, control to select the third antenna is performed. The mobile communication terminal according to the item. The mobile communication terminal is
The mobile communication terminal according to any one of claims 1 to 4, wherein the mobile communication terminal is used in a terminal in which a fourth antenna is deleted from a mobile communication terminal having the antenna control means. For the first and second antennas that can use one frequency band, and the third and fourth antennas that can use the other frequency band, the first and third antennas are in one place, When the antenna is switched between four antennas designed to be mounted at the other location of the fourth antenna, antenna control that can be switched between antennas installed in the same frequency band and at the same position In a mobile communication terminal including means,
First to third antennas;
A logic gate that inverts an instruction to select the fourth antenna of the antenna control means to an instruction not to select the antenna;
The switching means performs control to select a remaining antenna without selecting the fourth antenna when the antenna to be switched is the fourth antenna when switching the antenna being used. Antenna switching control method. Antenna switching control method
It is performed by changing from an antenna selection signal that designates the currently selected antenna output from the antenna switching means to an antenna selection signal that designates the antenna corresponding to the antenna switching destination,
7. The antenna switching control method according to claim 6, wherein an antenna selection signal designating an absent antenna is changed to an antenna selection signal designating another remaining antenna by the control. The antenna selection signal is
Position specification signal to specify the position,
And a signal that designates an antenna to be selected from a combination of frequency band designation signals that designate frequency bands to be used.
9. The antenna selection signal for designating an absent antenna by the control designates a remaining antenna by changing one of the signals. Antenna switching control method. 9. When switching a frequency band, when switching from the second antenna to the fourth antenna, control is performed to select the third antenna. The antenna switching control method according to Item. The antenna switching control method is:
10. The antenna switching control method according to claim 6, wherein the antenna switching control method is used in a terminal in which a fourth antenna is deleted from a mobile communication terminal having the antenna control means.   A mobile communication terminal capable of using the antenna switching method according to any one of claims 6 to 10. For the first and second antennas that can use one frequency band, and the third and fourth antennas that can use the other frequency band, the first and third antennas are in one place, An antenna control means for switching between the antennas installed in the same frequency band and at the same position when the antenna is switched between the four antennas designed to be mounted in the other place of the fourth antenna;
First to third antennas;
In a mobile communication terminal having a logic gate that reverses an instruction to select the fourth antenna of the antenna control means to an instruction not to select the antenna,
When the antenna to be switched is the fourth antenna when the antenna being used is switched,
An antenna switching control program comprising a remaining antenna selection step for selecting a remaining antenna without selecting the absent antenna. The instruction is an antenna selection signal composed of a signal specifying a predetermined frequency band and a signal specifying a predetermined position, and the switching is performed by inverting the signal logic of the antenna selection signal. The antenna switching program according to claim 12. The antenna switching program is
When a predetermined condition is met and antenna switching is performed in the same frequency band,
A first measurement step of measuring a reception level of a switching source antenna currently in use;
A second measurement step of measuring the reception level of the switching destination antenna;
A comparison step of comparing the reception levels of both of the antennas;
As a result of the comparison, an antenna determination step for determining an antenna having a good reception level;
An antenna signal switching step of switching to a signal using a specific antenna based on the result of the antenna determination step;
When performing antenna switching of a mobile communication terminal, a frequency band confirmation step for confirming a frequency band used in advance is added, and when an absent antenna is included in the frequency band confirmed by the frequency band confirmation step, 14. The processing terminal antenna switching program according to claim 13, wherein the second measurement step is omitted. The antenna switching program is
When switching to an antenna of a different frequency band, when the antenna to be switched to is a fourth antenna, there is a remaining antenna selection step of selecting by changing to the third antenna that can use the same frequency band as the fourth antenna The antenna switching program according to any one of claims 13 and 14, characterized in that The antenna switching program is
The antenna switching program according to any one of claims 12 to 15, wherein the antenna switching program is used in a terminal in which a fourth antenna is deleted from a mobile communication terminal having the antenna control means.   A mobile communication terminal capable of using the antenna switching program according to any one of claims 12 to 16.

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