JP4583210B2 - Wireless communication device and mobile phone terminal - Google Patents

Description

  The present invention relates to a wireless communication apparatus and a mobile phone terminal that perform wireless communication using a plurality of frequency bands.

  In recent years, frequencies used in mobile phone terminals have been diversified. For example, it is expected that a single mobile phone terminal will handle a plurality of frequency bands such as dual band and triple band.

  FIG. 3 shows a schematic configuration example of a wireless communication terminal capable of realizing wireless communication using a plurality of different frequency bands. Note that the example of FIG. 3 shows details only of the internal configuration of the receiving unit 101 that performs diversity reception.

  In FIG. 3, a signal received by one diversity antenna 110 is amplified by a low noise amplifier (LNA) 111, and a filtering process and an image removal process are performed by a filter 112 to pass a predetermined RF band. Then, it is sent to the mixer 113.

  The mixer 113 includes local oscillations of different frequencies (f = f1, f = f2, f = f3,...) Output from a plurality of voltage controlled oscillators (VCOs) 131, 132, 133,. Of the signals (hereinafter referred to as local signals), a local signal having a desired frequency selected by the local signal changeover switch 134 is supplied. As a result, the mixer 113 performs frequency conversion of the received signal sent from the filter 112 using the local signal selected by the local signal switch 134. That is, in the configuration of FIG. 3, the local signal selector switch 134 selects a local signal having a desired frequency from the plurality of local signals according to the frequency band used for wireless communication. The local signal changeover switch 134 is controlled by a CPU (not shown).

  The received signal frequency-converted by the mixer 113 is subjected to a low-pass filtering process by the filter 114 and then sent to the demodulator 115.

  The demodulator 115 demodulates the received signal sent from the filter 114 and sends the processed signal to the baseband circuit 105.

  The baseband circuit 105 performs, for example, despreading processing, deinterleaving processing, error correction processing, and the like on the received signal after the demodulation processing, and the obtained reception data is transferred to a subsequent configuration (for example, a CPU or the like) not shown. Output.

  Further, the signal received by the other diversity antenna 120 is amplified by a low noise amplifier (LNA) 121 via a duplexer 103, and a filtering process and an image removing process for allowing a filter 122 to pass through a predetermined RF band. After being performed, it is sent to the mixer 123.

  As in the case of the mixer 113, the mixer 123 is supplied with a local signal having a frequency selected by the local signal selector switch 134. As a result, the mixer 123 performs frequency conversion of the received signal sent from the filter 122 using the local signal selected by the local signal changeover switch 134.

  After that, the received signal frequency-converted by the mixer 123 is subjected to a low-pass filtering process by the filter 124 and is then demodulated by the demodulator 125 before being sent to the baseband circuit 105.

  On the other hand, the transmission signal generated by the error correction code addition, interleaving processing, and spreading processing in the baseband circuit 105 is sent to the transmission unit 102.

  The transmission unit 102 performs a process of converting the transmission signal of the baseband frequency to the RF band, a process of amplifying the transmission signal to a predetermined transmission power, and the like. The transmission signal output from the transmission unit 102 is transmitted to the antenna 120 via the duplexer 103 and transmitted from the antenna 120.

  For example, in Japanese Patent Laid-Open No. 9-18378 (Patent Document 1), a single local oscillator is used for both transmission and reception, so that it is small in size and does not generate unnecessary spurious during transmission. A wireless circuit for multiplex communication is disclosed.

  Also, for example, in Japanese Patent Application Laid-Open No. 2003-209480 (Patent Document 2), a clock generator for a telephone body and a clock frequency are integer multiples of a reference frequency for an FM radio receiver and demodulated. A telephone device that is set to a frequency that is an integral multiple of the frequency for use, and the clock of the clock generator for the telephone body is shared as the system clock of the FM radio receiver, thereby reducing the size and current consumption. Is disclosed.

Japanese Patent Laid-Open No. 9-18378 (FIG. 1) JP 2003-209480 A (FIG. 1)

  Here, in order to realize wireless communication using a plurality of different frequency bands, as shown in FIG. 3 described above, each of different frequencies (f = f1, f = f2, f = f3,...). A plurality of voltage controlled oscillators (VCOs) 131, 132, 133,... That output local signals are required, and an increase in the size and cost of the apparatus cannot be avoided. There is a problem that the mounting area is consumed.

  On the other hand, as in the techniques described in Japanese Patent Laid-Open Nos. 9-18378 and 2003-209480, the size of the apparatus can be increased by using a local oscillator or a clock generator. It is also possible to suppress the cost increase. However, in the case of the techniques described in these publications, in any case, wireless communication using only one frequency can be performed, and wireless communication using a plurality of frequencies cannot be performed. In order to perform radio communication using frequencies, it is necessary to prepare a plurality of local oscillators and clock generators for each of the plurality of frequencies, which inevitably increases the size and cost of the apparatus.

  In addition, for example, when wireless communication using a plurality of frequencies is put into practical use, it is highly likely that wireless communication using the plurality of frequencies at the same time will be desired in the future. The technique described in FIG. 3 and Japanese Patent Laid-Open Nos. 9-18378 and 2003-209480 cannot be dealt with.

  The present invention has been proposed in view of such circumstances, and enables wireless communication using a plurality of different frequency bands while suppressing increase in size and cost of the apparatus, and further in the future. Another object of the present invention is to provide a wireless communication device and a mobile phone terminal that can cope with a case where wireless communication using a plurality of frequencies simultaneously is desired.

The wireless communication device of the present invention uses a first oscillation signal generation unit that generates a first oscillation signal used for a predetermined wireless communication function, and the first oscillation signal as a local oscillation signal. A first communication unit that performs wireless communication using a communication function, and a second communication unit that is used for a function different from the predetermined wireless communication function and that oscillates at at least one frequency different from the frequency of the first oscillation signal. A second oscillation signal generation unit that generates an oscillation signal, a mixing unit that generates a third oscillation signal by mixing the first oscillation signal and the second oscillation signal, and a frequency used when performing wireless communication an oscillation signal selector for selecting one of the first oscillation signal and the third oscillation signal according to the band, using the oscillation signal selected by the oscillation signal selector as the local oscillation signal, performs radio communication by having a second communication unit, To solve the problems mentioned.

The cellular phone terminal of the present invention uses a first oscillation signal generation unit for generating a first oscillation signal used for a radio telephone communication function, and the first oscillation signal as a local oscillation signal. A first communication unit that performs wireless telephone communication using a communication function, and a second oscillation signal that is used for a function different from the wireless telephone communication function and that oscillates at at least one frequency different from the frequency of the first oscillation signal A second oscillation signal generation unit that generates a first oscillation signal, a mixing unit that generates a third oscillation signal by mixing the first oscillation signal and the second oscillation signal, and a frequency band used for wireless communication. in response, the oscillation signal selector for selecting either the first oscillation signal and the third oscillation signal, and using the oscillation signal selected by the oscillation signal selector as the local oscillation signal, performs radio communication No. by having the second communication unit, the upper To solve the problem.

  That is, according to the present invention, the wireless communication using the first oscillation signal as the local oscillation signal and the third oscillation signal obtained by mixing the first and second oscillation signals are used as the local oscillation signal. Switching between wireless communication can be selected according to the frequency band used when performing wireless communication.

  In addition, according to the present invention, wireless communication using the first oscillation signal as the local oscillation signal and the third oscillation signal obtained by mixing the first and second oscillation signals are used as the local oscillation signal. Wireless communication can be performed simultaneously.

  In the present invention, wireless communication using the first oscillation signal as the local oscillation signal and wireless communication using the third oscillation signal obtained by mixing the first and second oscillation signals as the local oscillation signal are performed wirelessly. Since switching can be selected according to the frequency band used for communication, wireless communication using a plurality of different frequency bands can be realized while suppressing an increase in size and cost of the apparatus.

  In the present invention, the wireless communication using the first oscillation signal as the local oscillation signal and the wireless communication using the third oscillation signal obtained by mixing the first and second oscillation signals as the local oscillation signal. Since it is possible to perform communication simultaneously, wireless communication using a plurality of frequencies simultaneously is possible.

  Hereinafter, an embodiment of a wireless communication device and a mobile phone terminal according to the present invention will be described with reference to the drawings.

  In the present embodiment, a mobile phone terminal is cited as an example of the present invention. Of course, the contents described here are merely examples, and the present invention is not limited to this example.

[First Embodiment]
FIG. 1 shows a schematic configuration example of a mobile phone terminal according to the first embodiment of the present invention capable of realizing wireless communication using a plurality of different frequency bands. Note that the example of FIG. 1 shows details only of the internal configuration of the reception unit 1 that performs diversity reception.

  In FIG. 1, a signal received by a diversity antenna 10 of one receiving system is amplified by a low noise amplifier (LNA) 11, and a filtering process and an image removing process in which a filter 12 passes a predetermined RF band. Is sent to the mixer 13.

  Although details will be described later, the mixer 13 is supplied with a local signal having a frequency corresponding to a frequency band used for wireless communication. As a result, the mixer 13 performs frequency conversion of the reception signal sent from the filter 12 using the local signal.

  The received signal frequency-converted by the mixer 13 is subjected to low-pass filtering processing by the filter 14 and then sent to the demodulator 15.

  The demodulator 15 demodulates the received signal sent from the filter 14. The received signal demodulated by the demodulator 15 is sent to a baseband circuit (not shown) via a terminal 16.

  Note that the baseband circuit performs, for example, despreading processing, deinterleaving processing, error correction processing, etc. on the received signal after the demodulation processing, and the obtained received data is configured in a later stage (for example, a CPU). Output to.

  Further, the signal received by the diversity antenna 20 of the other receiving system is amplified by the low noise amplifier (LNA) 21 via the duplexer 3, and the filtering process and image for allowing the filter 22 to pass a predetermined RF band. After the removal process is performed, it is sent to the mixer 23.

  Although details will be described later, a local signal having a frequency corresponding to a frequency band used for wireless communication is supplied to the mixer 23 as in the case of the mixer 13. As a result, the mixer 23 performs frequency conversion of the received signal sent from the filter 22 using the local signal selected by the local signal changeover switch 34.

  Thereafter, the received signal frequency-converted by the mixer 23 is subjected to a low-pass filtering process by a filter 24, and then a demodulation process by a demodulator 25, and then a baseband circuit (not shown) via a terminal 26. Sent to.

  On the other hand, a transmission signal generated by adding an error correction code in the baseband circuit, interleaving processing, and spreading processing is sent to the transmitting unit 2 via the terminal 4.

  The transmission unit 2 performs a process of converting the transmission signal of the baseband frequency to the RF band, a process of amplifying the transmission signal to a predetermined transmission power, and the like. The transmission signal output from the transmission unit 2 is transmitted to the antenna 20 via the duplexer 3 and is transmitted from the antenna 20.

  Here, in the mobile phone terminal according to the first embodiment of the present invention, a local signal having a frequency corresponding to a frequency band used for wireless communication is generated by the configuration described below, and the local signal is converted to the mixer 13. To the mixer 23.

  In recent mobile phone terminals, in addition to the telephone function, various functions (applications) that use RF devices such as an FM radio broadcast reception function, a television broadcast reception function, a wireless LAN communication function, and a Bluetooth communication function, respectively. ) Is installed. Further, each RF device used by each of these functions is equipped with a voltage controlled oscillator (VCO) in order to independently generate a local signal.

  In the mobile phone terminal according to the first embodiment of the present invention, as shown in FIG. 1, a voltage controlled oscillator 31 mounted on these RF devices (in FIG. 1, only one RF device 30 is shown as an example). Is used to generate an RF local signal having a frequency necessary for the telephone function.

  More specifically, in the mobile phone terminal of the first embodiment shown in FIG. 1, the local signal LOa having the frequency (f = fa) generated by the voltage controlled oscillator 31 of the RF device 30 is the mixer 32. Is supplied to one input terminal.

  The other input terminal of the mixer 32 is supplied with a local signal LO1 having a frequency (f = f1) generated by the voltage controlled oscillator 34 when the open / close switch 33 is closed.

  Thus, when the open / close switch 33 is closed, the mixer 32 causes the local signal LOa having the frequency fa generated by the voltage controlled oscillator 31 of the RF device 30 and the local signal having the frequency f1 generated by the voltage controlled oscillator 34 to be generated. LO1 will be mixed. A local signal LO2 having a frequency (f = f1 + fa or f1-fa) obtained by mixing the local signal LOa and the local signal LO1 by the mixer 32 is sent to the switched terminal a of the changeover switch 35.

  The local signal LO1 having the frequency f1 generated by the voltage controlled oscillator 34 is also sent to the switched terminal b of the changeover switch 35. The common terminal of the changeover switch 35 is connected to the mixers 13 and 23.

  The changeover switch 35 and the opening / closing switch 33 are switched and opened / closed by a CPU (not shown) based on a frequency band used for wireless communication. The CPU selects the switched terminal a of the changeover switch 35 and Control is performed so that closing of the open / close switch 33 is interlocked, and selection of the switched terminal b of the switch 35 is interlocked with opening of the open / close switch 33.

  Therefore, when the switched terminal a side of the changeover switch 35 is selected and the open / close switch 33 is controlled to close, the mixers 13 and 23 receive the frequency (f) where the local signal LOa and the local signal LO1 are mixed. = F1 + fa or f1-fa) local signal LO2 is supplied. On the other hand, when the switchable terminal b side is selected by the switch 35 and the opening / closing switch is controlled to open, the mixers 13 and 23 are supplied. Is supplied with the local signal LO1 having the frequency f1.

  As described above, in the mobile phone terminal according to the first embodiment shown in FIG. 1, the frequency fa from the voltage controlled oscillator 31 of the RF device 30 that is used in a function different from the telephone function. A local signal LO2 having a frequency (f = f1 + fa or f1-fa) obtained by mixing the local signal LO1 with the local signal LOa and a local signal LO1 having a frequency f1 from the voltage controlled oscillator 34 are switched and used, thereby being newly added. There is no need to provide a voltage controlled oscillator, and wireless communication using a plurality of different frequency bands is realized while suppressing an increase in size and cost of the apparatus.

  In the first embodiment, an example in which the local signal LO2 and the local signal LO1 are switched and used has been described. However, a local signal generated by a voltage-controlled oscillator of another RF device is used. By performing the same mixing process as described above, it is possible to switch between three or more local signals.

  In addition, since the voltage controlled oscillator 31 of the RF device 30 can finely adjust the frequency fa of the local signal LOa, the mobile phone terminal according to the present embodiment can finely adjust the frequency fa as necessary. By adjusting the frequency, the frequency of the local signal LO2 output from the mixer 32 can be finely adjusted.

[Second Embodiment]
FIG. 2 shows a schematic configuration example of a mobile phone terminal according to the second embodiment of the present invention capable of simultaneously realizing wireless communication using a plurality of different frequency bands. Note that the example of FIG. 2 shows only the internal configuration of the receiving unit 1 in detail. Further, in the mobile phone terminal of the second embodiment shown in FIG. 2, the same constituent elements as those of the mobile phone terminal of the first embodiment described above are denoted by the same reference numerals as those in FIG. Detailed description is omitted.

  In the mobile phone terminal according to the second embodiment, local signals of a plurality of frequency bands used for wireless communication are generated with the configuration described below, and the local signals of these frequencies are supplied to the mixers 13 and 23. It is made like that.

  More specifically, in the mobile phone terminal of the second embodiment shown in FIG. 2, the local signal LOa of the frequency (f = fa) generated by the voltage controlled oscillator 31 of the RF device 30 is sent to the mixer 32. Entered.

  In the mobile phone terminal of the second embodiment, the local signal LO1 having the frequency f1 generated by the voltage controlled oscillator 34 is supplied to the mixer 23 of the other receiving system and is shared by the changeover switch 43. Also supplied to terminals.

  The switched terminal a of the changeover switch 43 is connected to the mixer 32. Accordingly, when the switched terminal a is selected by the changeover switch 43, the mixer 32 is supplied with the local signal LO1 having the frequency (f = f1) generated by the voltage controlled oscillator 34. As a result, the mixer 32 mixes the local signal LOa having the frequency fa generated by the voltage controlled oscillator 31 of the RF device 30 with the local signal LO1 having the frequency f1 generated by the voltage controlled oscillator 34. A local signal LO2 having a frequency (f = f1 + fa or f1-fa) obtained by mixing the local signal LOa and the local signal LO1 in the mixer 32 is sent to the switched terminal a of the changeover switch 42.

  The changeover switch 42 has a switchable terminal b connected to the switchable terminal b of the switch 43 and a common terminal connected to the one receiving system mixer 13. The changeover switch 42 and the changeover switch 43 are controlled by a CPU (not shown) based on the frequency band used for wireless communication. The CPU selects the changeover terminal a of the changeover switch 43 and Switching control is performed so that selection of the switched terminal a of the changeover switch 42 is interlocked, and selection of the switched terminal b of the changeover switch 43 and selection of the switched terminal b of the changeover switch 42 are interlocked. Thus, when the switched terminal a side of the selector switch 43 is selected and the switched terminal a side of the selector switch 42 is selected and controlled, the local signal LOa and the local signal LO1 are mixed in the mixer 13. The local signal LO2 having a frequency (f = f1 + fa or f1-fa) is supplied, and the mixer 23 at this time is supplied with the local signal LO1 having the frequency f1.

  On the other hand, when the switched terminal b side of the selector switch 43 is selected and the switched terminal b side of the selector switch 42 is selected and controlled, the local signal LO1 of the frequency f1 is supplied to both the mixer 13 and the mixer 23. It will be.

  As described above, in the mobile phone terminal of the second embodiment shown in FIG. 2, when the switchable terminal a is selected by both the changeover switches 42 and 43, the voltage controlled oscillator 31 of the RF device 30 is selected. The local signal LO2 having a frequency (f = f1 + fa or f1−fa) obtained by mixing the local signal LO1 with the local signal LOa having the frequency fa is sent to the mixer 13, while the mixer 23 receives the frequency f1 from the voltage controlled oscillator 34. Wireless signal using the local signals LO1 and LO2 of two different frequencies is simultaneously performed, that is, it is not necessary to provide a separate voltage-controlled oscillator, and the size of the apparatus can be increased. Wireless communication using different frequency channels simultaneously becomes possible while suppressing an increase in cost. When performing simultaneous wireless communication of different frequency channels in this way, the voltage controlled oscillator 31 of the RF device 30 is selected to generate a local signal having a frequency fa that is distant from the frequency f1 of the local signal LO1. In order to prevent crosstalk, ensure sufficient isolation.

  Further, in the mobile phone terminal of the second embodiment, when the switched terminal b is selected by both the changeover switches 42 and 43, the local signal LO1 of the frequency f1 from the voltage controlled oscillator 34 is supplied to the mixers 13 and 23. As a result, diversity wireless communication using the antennas 10 and 20 is performed.

  In the second embodiment, the local signal LO2 and the local signal LO1 are used at the same time. However, the above-described local signal generated by a voltage-controlled oscillator of another RF device is used. By performing the same switch switching and mixing process, wireless communication using three or more local signals simultaneously becomes possible.

  According to the mobile phone terminal of the second embodiment, since wireless communication can be performed simultaneously using a plurality of frequency bands, for example, while making a call using one receiving system, the other receiving system is used. To send and receive e-mails, to make calls using one receiving system, to receive television broadcasts and radio broadcasts using the other receiving system, or to make calls using one receiving system While the other receiving system is connected to the Internet or wireless LAN, or one receiving system receives a signal of a certain frequency channel and the other receiving system receives a signal of another frequency channel. In such a case, the reception frequency channels in the one reception system and the other reception system can be switched to each other as necessary.

[Summary]
As described above, in the mobile phone terminal according to the first and second embodiments of the present invention, the local signal used in the RF device for a function different from the telephone function and the local signal for the telephone function are obtained. By mixing, it is not necessary to provide a separate voltage-controlled oscillator, and wireless communication using a plurality of different frequency bands can be realized while suppressing an increase in size and cost of the apparatus. In the mobile phone terminal according to the second embodiment of the present invention, wireless communication can be performed simultaneously using a plurality of different frequency bands.

  The description of each embodiment described above is an example of the present invention. For this reason, the present invention is not limited to the above-described embodiment, and it is needless to say that various modifications can be made according to the design or the like as long as the technical idea according to the present invention is not deviated.

  The wireless communication device of the present invention is not limited to a mobile phone terminal, and can also be applied to a PDA device (PDA: Personal Digital Assistants) having a wireless communication function, a notebook personal computer, a portable electronic game device, and the like. is there.

It is a figure which shows the schematic internal circuit structure of the radio | wireless communication system of the mobile telephone terminal of the 1st Embodiment of this invention. It is a figure which shows the schematic internal circuit structure of the radio | wireless communication system of the mobile telephone terminal of the 2nd Embodiment of this invention. 1 is a diagram illustrating a schematic internal circuit configuration of a general wireless communication apparatus that performs wireless communication in a plurality of frequency bands by switching and using a plurality of voltage controlled oscillators. FIG.

Explanation of symbols

  1 receiver, 2 transmitter, 3 duplexer, 4, 16, 26 terminals, 10, 20 antenna, 11, 21 low noise amplifier (LNA), 12, 14, 22, 24 filter, 13, 23, 32 mixer, 15 , 16 Demodulator, 30 RF device, 31, 34 Voltage controlled oscillator (VCO), 33 Open / close switch, 35, 42, 43 selector switch

Claims (3)

A first oscillation signal generator for generating a first oscillation signal used for a given wireless communication function,
A first communication unit that uses the first oscillation signal as a local oscillation signal and performs wireless communication by the predetermined wireless communication function;
The above predetermined wireless communication function is used to separate functions, the second oscillation signal generator for generating a second oscillation signal that oscillates at least one frequency different from the frequency of the first oscillation signal,
A mixing unit that mixes the first oscillation signal and the second oscillation signal to generate a third oscillation signal;
An oscillation signal selection unit that selects either the first oscillation signal or the third oscillation signal according to a frequency band used when performing wireless communication;
The oscillation signal oscillating signal selected by the selection unit is used as local oscillation signals, radio communications device that having a second communication unit that performs wireless communication. When the first oscillation signal is selected in the oscillation signal selection unit, a wireless communication apparatus according to claim 1, wherein performing diversity communication by the first communication unit and the second communication unit. A first oscillation signal generator for generating a first oscillation signal used in the wireless telephone communication function,
A first communication unit that uses the first oscillation signal as a local oscillation signal and performs radio telephone communication by the radio telephone communication function;
A second oscillation signal generating unit that is used for a function different from the radio telephone communication function, and that generates a second oscillation signal that oscillates at at least one frequency different from the frequency of the first oscillation signal;
A mixing unit that mixes the first oscillation signal and the second oscillation signal to generate a third oscillation signal;
An oscillation signal selection unit that selects either the first oscillation signal or the third oscillation signal according to a frequency band used when performing wireless communication;
The oscillation signal oscillating signal selected by the selection unit is used as the local oscillation signal, mobile phone terminals that have a second communication unit that performs wireless communication.

Images