JP2010171898A - Multiband radio communication device - Google Patents

Abstract

The present invention provides a multiband wireless communication apparatus capable of simplifying the circuit configuration even when a plurality of used frequency bands are relatively far apart.
A baseband unit generates a baseband signal for information to be transmitted. The first frequency synthesizer 2 oscillates the IF signal so that the intermediate frequency F _IF is the same as the first use frequency band F _A. The first mixer 3, using the IF signal from the first frequency synthesizer 2, upconverts baseband signals from the baseband unit 1 to the first transmission signal of the first usable frequency band F _A. Second mixer 6, using the local oscillation signal from the second frequency synthesizer 5, the first transmission signal from the first mixer 3, up-converts the second transmission signal of the second usable frequency band F _B.
[Selection] Figure 1

Description

  The present invention relates to a multiband wireless communication apparatus used in a wireless communication system that performs wireless communication using transmission signals in a plurality of discontinuous use frequency bands.

  Due to the spread of systems using wireless communication in recent years, there is an increasing demand for expanding the frequency band allocated to each system, particularly in systems with a high penetration rate. For example, when a use frequency band is added to a certain system later, the use frequency band used for one system may become a plurality of use frequency bands that are discontinuous rather than being continuous. In such a multi-band system, it is necessary to make the wireless communication device compatible with a plurality of use frequency bands. For example, a mobile terminal can support both of the two use frequency bands. Products have been proposed.

  A conventional multiband-compatible wireless communication apparatus used in such a multiband system has a transmission circuit and a reception circuit corresponding to each of the two used frequency bands, and is used for communication purposes. Accordingly, the used frequency band and circuit were selected. That is, in such a conventional multiband-compatible wireless communication apparatus, two or more transmission circuits and reception circuits are used.

  In particular, in such a wireless communication apparatus, one frequency synthesizer (frequency oscillating unit) that oscillates each signal in an intermediate frequency (IF), a first used frequency band, and a second used frequency band is used. In addition, one signal conversion mixer is also used for each of the intermediate frequency, the first use frequency band, and the second use frequency band. For this reason, the circuit configuration has been enlarged.

On the other hand, for example, in a conventional dual-band wireless communication apparatus as shown in Patent Document 1, the circuit configuration is simplified by reducing the number of frequency synthesizers and mixers. FIG. 5 is a configuration diagram showing a conventional dual-band wireless communication apparatus as shown in Patent Document 1. In FIG. In this case, for example, the first use frequency band F _A is 940 MHz, the second use frequency band F _B is 1453 MHz, and the intermediate frequency F _IF is 255.5 MHz.

  In FIG. 5, a conventional dual-band wireless communication apparatus includes a baseband unit 101, a first frequency synthesizer 102, a first mixer 103, a second frequency synthesizer 104, a second mixer 105, a transmission frequency selection switch 106, and a pair of BPFs. (Band Pass Filter) 107A and 107B, a pair of amplifiers 108A and 108B, and a pair of antennas 109A and 109B.

The first mixer 103 multiplies the baseband signal generated by the baseband unit 101 and the signal of the intermediate frequency F _IF generated by the first frequency synthesizer 102, so that the frequency of the baseband signal is the intermediate frequency F. Upconvert to _IF . The second frequency synthesizer 104 oscillates a local oscillation signal having a frequency obtained by subtracting the intermediate frequency F _IF from half the sum of the first used frequency band F _A and the second used frequency band F _B.

The second mixer 105 _multiplies the baseband signal of the intermediate frequency F _IF from the first mixer 103 and the local oscillation signal from the second frequency synthesizer 104 to change the frequency of the baseband signal to the first used frequency band F. and up-converted to _a and the frequency of the half value of the sum of the second usable frequency band _{F B,} to generate a transmission signal of the RF (Radio frequency).

The transmission frequency selection switch 106 can switch the transmission path of the transmission signal from the second mixer 105 from one of the BPF 107A side and the BPF 107B side to the other. The frequency pass characteristic of the BPF 107A corresponds to the first use frequency band F _A , and the frequency pass characteristic of the BPF 107B corresponds to the second use frequency band F _B.

Then, by transmitting a signal from the second mixer 105 is passed through the BPF107A or BPF107B, one signal of the first usable frequency band _{F A} and the second usable frequency band _{F B} is, amplifiers 108A and antenna 109A, or It is transmitted to the outside through the amplifier 108B and the antenna 109B. Therefore, in the conventional dual-band wireless communication apparatus as shown in Patent Document 1, the correspondence to the two used frequency bands is achieved by using the frequency synthesizers 102 and 104 and the mixers 103 and 105, one each for IF and RF. The configuration was simplified.

JP-A-5-244032

  Here, in recent years, in order to increase the area coverage ratio, for example, a system using a combination of a high frequency band such as a millimeter wave (for example, 30 G to 300 GHz) and a usage frequency band of several GHz is being proposed. It is assumed that there are cases where the frequency bands used in the multiband wireless communication system are separated. In such a multi-band wireless communication system that is separated from the usable frequency band, the circuit scale has been increased in order to realize a wireless communication device that supports all usable bands.

Moreover, in the conventional dual-band wireless communication apparatus as shown in Patent Document 1, for example, when the first and second use frequency bands F _A and F _B are relatively large apart (for example, when separated by 10 GHz or more), etc. The difference between the intermediate frequency F _IF and the first and second use frequency bands F _A and F _B also increases. This makes it difficult to set the intermediate frequency F _IF in the first frequency synthesizer 102, and this communication device cannot be used. Therefore, in such a case, the circuit configuration cannot be simplified.

  The present invention has been made to solve the above-described problems, and a multiband wireless communication apparatus capable of simplifying the circuit configuration even when a plurality of used frequency bands are relatively far apart. The purpose is to obtain.

  The multiband wireless communication apparatus according to the present invention includes a first use frequency band that is the lowest use frequency band among a plurality of discontinuous use frequency bands, and higher than the first use frequency band among the plurality of use frequency bands. A baseband unit that generates a baseband signal for information to be transmitted, and is used in a wireless communication system capable of performing wireless communication selectively using a second used frequency band that is a used frequency band; A first frequency oscillating unit that oscillates a signal of the intermediate frequency, and a signal from the first frequency oscillating unit, and a baseband signal from the baseband unit as a first used frequency band. A first frequency conversion unit that up-converts the first transmission signal, a second frequency oscillation unit that oscillates a signal having a frequency difference between the first use frequency band and the second use frequency band, A second frequency converter that upconverts the first transmission signal from the first frequency converter to a second transmission signal in the second used frequency band, using the signal from the wave number oscillator, the first transmission signal, and the second And a signal transmission unit capable of selectively amplifying the transmission signal and transmitting it to the outside.

  According to the multiband wireless communication device of the present invention, the first frequency oscillating unit oscillates a signal in the first used frequency band, which is the lowest used frequency band among the plurality of used frequency bands, as an intermediate frequency signal, The frequency conversion unit upconverts the baseband signal to the intermediate frequency to obtain the first transmission signal, and the second frequency conversion unit upconverts the first transmission signal to the second use frequency band to obtain the second transmission signal, thereby transmitting the signal. Since the unit can selectively amplify the first transmission signal and the second transmission signal and transmit them to the outside, the frequency oscillation unit and the frequency conversion unit for the first use frequency band or the intermediate frequency become unnecessary, and Since the intermediate frequency can be set without depending on the second used frequency band, the circuit configuration can be simplified even when a plurality of used frequency bands are relatively far apart. Kill.

It is a block diagram which shows the multiband radio | wireless communication apparatus by Embodiment 1 of this invention. FIG. 2 is an explanatory diagram for explaining a use frequency band used in the multiband wireless communication apparatus of FIG. It is a block diagram which shows the multiband radio | wireless communication apparatus by Embodiment 2 of this invention. It is a block diagram which shows the multiband radio | wireless communication apparatus by Embodiment 3 of this invention. It is a block diagram which shows the conventional dual band radio | wireless communication apparatus as shown in patent document 1. FIG.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.
Embodiment 1 FIG.
1 is a block diagram showing a multiband wireless communication apparatus according to Embodiment 1 of the present invention. FIG. 2 is an explanatory diagram for explaining a use frequency band used in the multiband wireless communication apparatus of FIG.
First, in the radio communication system in which the multiband radio communication apparatus of FIG. 1 is used, the first use frequency band F _A and the second use frequency which are two discontinuous (separate) use frequency bands as shown in FIG. band _{F B} is used. The first usable frequency band F _A, the lowest usable frequency band among a plurality of discontinuous frequency bands used. Further, the first usable frequency band F _A, for example, mainly used for communication of control information, a 5GHz band. Further, the first use frequency band F _A is composed of one channel f _A0 . The center frequency of the channel f _{A0 in} the first use frequency band F _A is, for example, 5.0 GHz.

The second use frequency band F _B is a use frequency band higher than the first use frequency band F _A among a plurality of discontinuous use frequency bands used. The second usable frequency band _{F B,} for example, mainly used for communications of the user data, a 60GHz band. Further, the second usable frequency band _{F B} is composed of a plurality of channels _f B0 _{~f BN.} The center frequencies of the plurality of channels f _{B0 to} f _BN in the second use frequency band F _B are, for example, 60.2 GHz to 62.2 GHz (0.4 GHz step variation), respectively.

  Next, in FIG. 1, the multiband wireless communication apparatus includes a baseband unit 1, a first frequency synthesizer 2 as a first frequency oscillating unit, a first mixer 3 as a first frequency converting unit, and a transmission frequency selection switch 4. And a second frequency synthesizer 5 as a second frequency oscillating unit, a second mixer 6 as a second frequency converting unit, a pair of amplifiers 7A and 7B, and a pair of antennas 8A and 8B.

The baseband unit 1 generates a baseband signal for information to be transmitted. First frequency synthesizer 2, the signal of the first usable frequency band F _A, oscillates as an IF signal is an intermediate frequency F _IF signal. That is, the first frequency synthesizer 2 oscillates an IF signal to an intermediate frequency F _IF is equal to the first usable frequency band F _A. The first mixer 3, using the IF signal from the first frequency synthesizer 2, up baseband signal from the baseband unit 1 to the first transmission signal of the first usable frequency band F _A (RF transmission signal) conversion To do.

  The transmission frequency selection switch 4 has first to third fixed contacts 4a to 4c and a movable contact 4d. The first fixed contact 4 a is electrically connected to the first mixer 3. Further, the transmission frequency selection switch 4 moves the electric circuit of the first transmission signal from the first mixer 3 and the first fixed contact 4a to the second fixed contact 4b side and the third fixed contact 4c side by moving the movable contact 4d. It is possible to switch from one to the other. The switching of the electric path by the transmission frequency selection switch 4 is controlled by a communication control unit (not shown) that performs communication control.

The second frequency synthesizer 5 has a difference frequency (about 55 GHz) between the center frequency of the channel f _{A0 in} the first use frequency band F _A and the center frequency of the channels f _{B0 to} f _BN in the second use frequency band F _B. Oscillate local oscillation signal. The second frequency synthesizer 5, (not shown) the second usable frequency band for the channel selecting means for selecting a desired channel among a plurality of channels f _B0 ~f _BN belonging to the second usable frequency band F _B have. By the second use frequency band channel selection means, the center frequency of the local oscillation signal is variable so as to correspond to the center frequencies of the channels f _{B0 to} f _BN .

The second mixer 6 is electrically connected to the third fixed contact 4 c of the transmission frequency selection switch 4. That is, the second mixer 6 receives the first transmission signal from the first mixer 3 when the electric circuit from the first fixed contact 4 a to the third fixed contact 4 c is formed by the transmission frequency selection switch 4. The second mixer 6, using the local oscillation signal from the second frequency synthesizer 5, the first transmission signal from the first mixer 3, the transmission of the second transmission signal (RF of the second usable frequency band F _B Signal).

The amplifier 7A is electrically connected to the second fixed contact 4b of the transmission frequency selection switch 4. That is, when the electric circuit from the first fixed contact 4 a to the second fixed contact 4 b is formed by the transmission frequency selection switch 4, the amplifier 7 A receives the first transmission signal from the first mixer 3. The amplifier 7A is electrically connected to the antenna 8A. Transmission characteristics of the amplifier characteristics and the antenna 8A amplifiers 7A corresponds to the frequency band, namely the first usable frequency band F _A of the first transmission signal. The amplifier 7A and the antenna 8A amplify the first transmission signal and transmit it to the outside.

The amplifier 7 </ b> B is electrically connected to the second mixer 6 and receives the second transmission signal from the second mixer 6. The antenna 8B is electrically connected to the amplifier 7B. Transmission characteristics of the amplifier characteristics and the antenna 8B amplifiers 7B corresponds to the frequency band, i.e. the second usable frequency band F _B of the second transmission signal. The amplifier 7B and the antenna 8B amplify the second transmission signal and transmit it to the outside.

  Here, the transmission frequency selection switch 4, the pair of amplifiers 7A and 7B, and the pair of antennas 8A and 8B constitute a signal transmission unit. That is, the signal transmission unit can selectively amplify the first transmission signal and the second transmission signal and transmit them to the outside.

Next, a signal flow when receiving the first transmission signal will be briefly described. If in a multi-band wireless communication device on the receiving side receives the signal of the first usable frequency band F _A, the signal received by the antenna passes through an RF circuit such as a filter. The signal that has passed through the RF circuit is down-converted to a baseband signal by being multiplied by the 5.0 GHz local oscillation signal output from the frequency synthesizer by the mixer. The down-converted signal is subjected to reception processing in the baseband unit.

In the multiband radio communication apparatus as described above, the first transmission signal of the first use frequency band F _A is transmitted by making the intermediate frequency F _{IF the} same as the first use frequency band F _A in the multiband radio communication system. In this case, the configuration of the RF circuit is only the amplifier 7A and the antenna 8A. With this configuration, it is possible to make the frequency synthesizer and a mixer for upconverting the intermediate frequency F _IF to the first usable frequency band F _A is unnecessary. The second mixer 6 upconverts the first transmission signal to the second usable frequency band F _B, by a second transmission signal, independent of the intermediate frequency F _IF in the second usable frequency band F _B It can be set. Therefore, in the multiband wireless communication apparatus as described above, the circuit configuration can be simplified even when the first and second used frequency bands F _A and F _B are relatively far apart.

Further, the second frequency synthesizer 5 has second used frequency band channel selecting means, and the second used frequency band channel selecting means allows the center frequency of the local oscillation signal to be the channel f _{B0 to} f _BN . It is variable to correspond to the center frequency. This configuration without increasing the number of frequency synthesizers, may correspond to a plurality of channel f _B0 ~f _BN belonging to the second usable frequency band F _B.

In the first embodiment, the first usable frequency band _{F A} is 5 GHz, the second usable frequency band _{F B} was described for an example of a dual-band system is 60 GHz. However, the combination of use frequency bands can be determined as appropriate, and may be, for example, a combination of an 800 MHz band and a 1.2 GHz band.

Embodiment 2. FIG.
In the first embodiment, the example using two use frequency bands (dual bands) has been described. On the other hand, in the second embodiment, an example using three use frequency bands (multiband) will be described.

  FIG. 3 is a block diagram showing a multiband wireless communication apparatus according to Embodiment 2 of the present invention. The multiband radio communication apparatus of the second embodiment further includes a third frequency synthesizer 9, a third mixer 10, an amplifier 7C, and an antenna 8C in addition to the configuration of the first embodiment (configuration shown in FIG. 1). Yes. Further, the transmission frequency selection switch 4 of the second embodiment further includes a fourth fixed contact 4e.

The third frequency synthesizer 9 oscillates a local oscillation signal having a frequency difference between the center frequency of the channels f _{C0 to} f _Cm of the third use frequency band F _C and the channel f _A0 center frequency of the first use frequency band F _A. To do. The third frequency band used F _C is the frequency band higher than the first usable frequency band F _A, and a different frequency band and the second usable frequency band F _B. Similarly to the second frequency synthesizer 5, the third frequency synthesizer 9 is a third used frequency band for selecting a desired channel among the plurality of channels f _{C0 to} f _Cm belonging to the third used frequency band F _C. Channel selection means (not shown).

  The third mixer 10 is electrically connected to the fourth fixed contact 4 e of the transmission frequency selection switch 4. The third mixer 10 receives the first transmission signal from the first mixer when the transmission frequency selection switch 4 forms an electric circuit from the first fixed contact 4a to the fourth fixed contact 4e.

The third mixer 10 uses the local oscillation signal of the third frequency band used F _C, up-converts the first transmission signal to the third transmission signal of the third frequency band used F _C. This third transmission signal is amplified by the amplifier 7C and transmitted from the antenna 8C to the outside. The transmission characteristics of the amplifier characteristics and the antenna 8C amplifier 7C, the frequency band of the third transmission signal, that is, corresponds to the first usable frequency band F _C. Other configurations are the same as those in the first embodiment.

In multi-band wireless communication device as described above, a configuration using three usable frequency band, even if the first to third frequency band used F _A to F _C is relatively far away, the implementation As in the first embodiment, the circuit configuration can be simplified. The same effect can be obtained even with a configuration using four or more used frequency bands.

Embodiment 3 FIG.
In the first and second embodiments, the first usable frequency band F _A has been described in the case of one channel. In contrast, in Embodiment 3, an example of a case where the first usable frequency band F _A contains multiple channels.

FIG. 4 is a block diagram showing a multiband radio communication apparatus according to Embodiment 3 of the present invention. In FIG. 4, the first frequency synthesizer 2 of the third embodiment selects a desired channel from the two channels f _A0 and f _A1 belonging to the first used frequency band F _A , similarly to the second frequency synthesizer 5. First frequency band channel selection means (not shown). Further, the second frequency synthesizer 5 of the third embodiment can change the center frequency of the local oscillation signal that it oscillates so as to correspond to the frequency of the local oscillation signal of the first frequency synthesizer 2.

For example, when the center frequency of the channel f _A0 is 5.0 GHz and the center frequency of the channel f _A1 is 5.1 GHz, the frequency of the local oscillation signal is set to 5.0 GHz by the channel selection unit for the first use frequency band. Any one of 5.1 GHz can be selected. Further, for example, when a 60.2 GHz channel is used in the second use frequency band F _B , the second frequency synthesizer 5 uses two channels f _A0 and f _A1 belonging to the first use frequency band F _A. Correspondingly, a local oscillation signal of 55.2 GHz or 55.1 GHz is oscillated. Other configurations are the same as those in the second embodiment.

In the multiband radio communication apparatus as described above, the first frequency synthesizer 2 has the second use frequency band channel selection means, and the first use frequency band channel selection means uses the center frequency of the local oscillation signal. Is variable so as to correspond to the center frequency of the channels f _A0 and f _A1 . With this configuration, it is possible to deal with the two channels f _A0 and f _A1 belonging to the first used frequency band F _A without increasing the number of frequency synthesizers.

In the third embodiment, there are two channels belonging to the first used frequency band F _A , but the present invention is not limited to this example, and there are three or more channels belonging to the first used frequency band F _A. There may be.

  1 baseband unit, 2 first frequency synthesizer (first frequency oscillating unit), 3 first mixer (first frequency converting unit), 4 transmission frequency selection switch, 5 second frequency synthesizer (second frequency oscillating unit), 6 Second mixer (second frequency converter), 7A-7C amplifier, 8A-8C antenna, 9 Third frequency synthesizer, 10 Third mixer.

Claims (3)

The first used frequency band that is the lowest used frequency band among the plurality of discontinuous used frequency bands, and the second used frequency that is higher than the first used frequency band among the plurality of used frequency bands. A multiband wireless communication device used in a wireless communication system capable of wireless communication selectively using a band,
A baseband unit that generates a baseband signal for information to be transmitted;
A first frequency oscillating unit configured to oscillate a signal of the first frequency in the first use frequency band,
A first frequency converter that up-converts a baseband signal from the baseband unit into a first transmission signal in the first used frequency band using a signal from the first frequency oscillator;
A second frequency oscillating unit for oscillating a signal having a frequency difference between the first used frequency band and the second used frequency band;
A second frequency converter that up-converts the first transmission signal from the first frequency converter to a second transmission signal in the second used frequency band using a signal from the second frequency oscillator;
A multiband wireless communication apparatus comprising: a signal transmission unit capable of selectively amplifying and transmitting the first transmission signal and the second transmission signal to the outside. The first frequency oscillating unit includes channel selection means for first use frequency band for selecting a desired channel from a plurality of channels belonging to the first use frequency band. The multiband wireless communication device described. The second frequency oscillating unit includes second used frequency band channel selection means for selecting a desired channel from a plurality of channels belonging to the second used frequency band. Or the multiband radio | wireless communication apparatus of Claim 2.

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