CN1250985A - Radio communication device, and integrated circuit used in such device - Google Patents

Abstract

To minimize complexity in the internal frequency configuration of equipment and increase in the number of parts caused by the complexity. In this multiband/multimode radio communication equipment, the oscillation frequency of an RF local synthesizer 17 is used, by changing a frequency dividing ratio corresponding to a communication mode through a variable frequency divider 22. A reception intermediate frequency is equalized in respective communication bands, and in the case of the same modulating system, a reception IF filter 5 and a reception intermediate frequency variable gain amplifier 6 are used in common. Moreover, the oscillation frequency of a local synthesizer 20 for quadrature modulation is used by changing the frequency dividing ratio corresponding to the communication mode as well. Furthermore, a transmission intermediate frequency variable gain amplifier 12 and a transmission intermediate frequency filter 13 are used in common at different transmission intermediate frequencies in respective communication bands.

Description

Wireless communication device and integrated circuit used in the device

The present invention relates to a multi-mode wireless communication device and a multi-band wireless communication terminal capable of performing communications using a plurality of wireless communication frequency bands and a plurality of wireless communication systems with one wireless communication terminal. In particular, it relates to a wireless communication device such as a wireless communication terminal capable of selectively using a PCS band CDMA system, a cellular band CDMA system, or an AMPS system, and an integrated circuit used in the device.

In the field of mobile communication, analog communication in a frequency band of 800 to 900 MHz has conventionally been performed. However, with the urgency of frequency resources and the development of various digital communication methods, the frequency band is changing from the previous use of analog communication to digital communication. Currently, digital mobile communication systems in the frequency band of 1800 to 2000 MHz are being utilized.

Under such circumstances, it is desired that the mobile communication terminal owned by the user be able to support various communication systems, and at the same time, be able to select a communication system according to service content, communication cost, or service provision area. However, if two communication systems using different frequency bands such as the 800-900MHz band and the 1800-2000MHz band are made to correspond to each other, the frequency structure inside the radio of the mobile communication terminal device will be complicated and the number of components will increase. Therefore, it is difficult to realize a mobile communication device that is small in size and light in weight.

FIG. 9 shows the configuration of a wireless unit of a conventional dual-band terminal. That is, it is a mobile communication terminal capable of selectively using multiple communication systems, for example, the PCS-CDMA system in the 1900MHz band used in the United States, and the cellular CDMA and cellular AMPS in the 800MHz band.

Operation of the receiving system In the case of PCS mode, the signal (1930.00～1989.95MHz) received by the antenna 1 is demultiplexed by the antenna duplexer 2, amplified in the low noise amplifier 3A, and passed through a bandpass filter (not shown in the figure) ) enters the down-converter 4A, mixes with the RF local signal (1719.62-1779.57MHz) used by the PCS, and converts the frequency into a receiving intermediate frequency (210.38MHz) used by the PCS.

Next, by only taking out the desired signal PCS-CDMA with receiving intermediate frequency filter 5A, by PCS with receiving intermediate frequency variable gain amplifier 6A amplified to a predetermined signal level, through channel switching switch 7 in quadrature modem 8 and quadrature modem 8 The inter-demodulation uses the local signal (210.38MHz) to mix and become the received CDMA baseband composite signal, implement appropriate filtering processing, A/D conversion processing, and input to the CDMA modulation and demodulation receiving unit.

On the other hand, in the case of the cellular CDMA mode and the AMPS mode, the signal (869.04-893.97 MHz) received by the antenna 1 is demultiplexed by the antenna duplexer 2, amplified in the low-noise amplifier 3B, and passed through a band-pass filter ( (not shown) enters the down-converter 4B, mixes with the RF local signal (964.42-979.35MHz) for cellular, and converts it into a receiving intermediate frequency (85.38MHz) for cellular.

Secondly, under the cellular CDMA mode, through the channel switch 9, the cellular CDMA receiving intermediate frequency filter 5B that only takes out the desired signal is amplified to a predetermined signal level with the cellular CDMA receiving intermediate frequency variable gain amplifier 6B, and passed through The channel changeover switch 7 mixes with the local signal (85.38MHz) for quadrature demodulation in the quadrature demodulator 8 to become a composite signal for receiving the CDMA baseband, implement appropriate filter processing, A/D conversion processing, and input to CDMA modulation and demodulation receiving unit.

In addition, in the cellular AMPS mode, through the channel switching switch 9, through the cellular AMPS receiving intermediate frequency filter 5C that only extracts the desired signal, after the predetermined frequency conversion, amplification, and FM detection processing are implemented in the cellular AMPS receiving intermediate frequency unit 10 , input to the receiving baseband unit (not shown) for AMPS.

As the operation of the transmission system, in the case of the PCS-CDMA mode and the cellular CDMA mode, the transmission baseband composite signal input from the CDMA modulation and demodulation transmission unit (not shown) is combined with the quadrature modulator 11 in the quadrature modulator 11. The machine signal is mixed, and the frequency is converted to the sending intermediate frequency (130.38MHz).

After the transmission intermediate frequency signal is amplified to a desired level by the transmission intermediate frequency variable gain amplifier 12, spurious components and noise components outside the desired frequency band are removed by the transmission intermediate frequency filter 13.

Under the PCS-CDMA mode, the sending intermediate frequency signal is input into the up-converter 15A for PCS-CDMA through the channel switching switch 14, mixed with the RF local signal for PCS, and converted into the PCS sending frequency (1850.00～1909.95MHz ). Then, the signal is amplified to a desired level by a power amplifier 16A through a band-pass filter and a driver amplifier (not shown), and transmitted from the antenna 1 through the antenna duplexer 2 .

In the cellular CDMA mode, the transmitting intermediate frequency signal is input to the cellular up-converter 15B through the channel switch 14, mixed with the cellular RF local signal, and converted to the cellular transmitting frequency (824.04-848.97MHz). Then, the signal is amplified to a desired level by the power amplifier 16B through a band-pass filter and a driver amplifier, and transmitted from the antenna 1 through the antenna duplexer 2 .

In the cellular AMPS mode, the transmission signal from the AMPS transmission baseband unit is input to the frequency control input terminal of the voltage-controlled oscillator (VCO) of the local frequency synthesizer 20 for quadrature modulation that generates the local signal for quadrature modulation, FM modulation is added to the local signal for quadrature modulation, and the signal is sent to the transmission intermediate frequency variable gain amplifier 12 by an appropriate method and amplified to a desired level. Subsequent operations are substantially the same as in the cellular CDMA mode described above.

The above-mentioned various local signals are respectively used in the RF local frequency synthesizer 17 for PCS, the RF local frequency synthesizer 18 for cellular, the local frequency synthesizer 19 for quadrature demodulation, and the local frequency synthesizer 20 for quadrature modulation. Generated in. Each frequency synthesizer is composed of VCO, loop filter, frequency divider, phase comparator and so on.

In addition, the local signal for quadrature demodulation and the local signal for quadrature modulation use two signals with a phase difference of 90 degrees. In order to generate these signals, a signal multiplied by 2 is generated in advance, and in the process of dividing it by 2, two signals with a phase difference of 90 degrees are obtained.

In this case, the frequency generated by the local frequency synthesizer 19 for quadrature demodulation is doubled at first, and is 420.76 MHz in the PCS mode and 260.76 MHz in the cellular mode. In addition, the local frequency synthesizer for quadrature modulation is 1260.76MHz.

However, the aforementioned conventional dual-band terminal has a problem that it cannot be small, lightweight, and inexpensive.

1. The number of frequency synthesizers is up to 4. In particular, RF local frequency synthesizers for PCS and RF local frequency synthesizers for cellular, which require low-noise performance, use relatively large and expensive modules as components for the VCO, so it is not possible to realize small and lightweight terminals and low prices.

2. Although receiving CDMA uses IF filters and receiving IF variable gain amplifiers to process similar received signals, in PCS-CDMA mode and cellular CDMA mode, two systems are required because the receiving IF is different. Since these components are also relatively large and expensive, it becomes an obstacle to realizing a terminal that is small, lightweight, and low-priced.

3. Since the generation frequency of the local frequency synthesizer for quadrature demodulation is 420.76MHz in PCS mode and 260.76MHz in cellular mode, there is a huge difference. Therefore, it is necessary to switch the loop constants that constitute the PLL according to the mode. , increasing the circuit scale. This point will also hinder the miniaturization, light weight and low price of the terminal.

Among conventional dual-band terminals, terminals that can selectively use PCS-CDMA mode, cellular CDMA mode, and cellular AMPS mode have been described. Problems 1 to 3 above also exist in the video terminal. In addition, the above-mentioned problems 1 and 3 also exist in a dual-frequency terminal capable of selectively using the PCS-CDMA mode and the cellular AMPS mode.

The object of the present invention is to solve the problems of the above-mentioned conventional dual-frequency terminal, and to provide a wireless terminal that can minimize the complexity of the internal frequency configuration of the device and the increase in the number of parts caused by it, and achieve small size, light weight and low price. communication device. Furthermore, the object is to provide an integrated circuit used in the wireless communication device.

In order to achieve the above object, the wireless communication device of the present invention is capable of selectively performing any one of communication using a first communication frequency band and communication using a second communication frequency band lower in frequency than the first communication frequency band. The device is characterized in that the oscillation frequency of the local signal oscillator that generates the radio frequency is selected as a common multiple of the local signal frequency required in each communication mode, these signals are generated by one system oscillator, and the distribution is changed according to the communication mode. Frequency ratio is used.

That is, in the wireless communication device of the present invention, the RF local frequency synthesizer that needs two systems conventionally used in each communication frequency band can be constituted with one system, so the parts of the VCO module are reduced, and the device is small and light. , Low price has effect.

In addition, the reception intermediate frequency is made the same when any communication frequency band is used, and the reception intermediate frequency filter and reception intermediate frequency amplifier can be shared when almost the same modulation method is used in both communication frequency bands.

By adopting such a configuration, since two systems of reception intermediate frequency filters and amplifiers conventionally used in each communication frequency band can be configured with one system, it is effective in terms of small size, light weight, and low price of the device.

In addition, the transmission intermediate frequencies in the respective communication frequency bands are set to an integer ratio to each other, and the oscillation frequency of the local signal oscillator for converting the transmission baseband signal into the transmission intermediate frequency signal is selected as the local frequency required in each communication mode. The common multiple of the signal is generated by a fixed frequency synthesizer and used by changing the frequency division ratio according to the communication mode.

According to such a configuration, the oscillation frequency of the oscillator generating the local signal can be fixed. That is, if the reception intermediate frequencies are made equal, conversely, the transmission intermediate frequencies differ among the respective communication frequency bands. However, if these frequencies are set so that these frequencies are an integer ratio to each other, the oscillation frequency of the oscillator that generates the local signal can be selected as a common multiple of the local frequency required in each communication mode, and the signal can be generated with a fixed oscillator , and use it by changing the frequency division ratio according to the communication mode. Therefore, since the oscillation frequency of the oscillator that generates the local signal can be fixed, it is not necessary to switch the loop constant in the local oscillator for quadrature modulation as in the past, so that the circuit can be simplified, and the device can be small and light. It is effective in terms of quantity and low price. In addition, by employing a configuration in which different transmission intermediate frequencies in the respective communication bands can be shared by the transmission intermediate frequency amplifier and the transmission intermediate frequency filter, it is also effective in terms of small size, light weight, and low price of the device.

Furthermore, in the device of the present invention, since at least part of the PLL circuits of the first and second oscillators and the first and second variable frequency dividers can be installed inside, it is made to have a function of selective frequency division according to the communication mode. Therefore, by using an integrated circuit having such a structure, it is possible to easily configure a wireless communication device.

FIG. 1 is a block diagram showing the configuration of a first embodiment of the wireless communication device of the present invention.

Fig. 2 is a block diagram showing the configuration of a second embodiment of the wireless communication device of the present invention.

Fig. 3 is a block diagram showing the configuration of a third embodiment of the wireless communication device of the present invention.

Fig. 4 is a block diagram showing the configuration of a fourth embodiment of the wireless communication device of the present invention.

Fig. 5 is a block diagram showing the configuration of a fifth embodiment of the wireless communication device of the present invention.

FIG. 6 shows, as a sixth embodiment of the wireless communication device of the present invention, desired characteristics of a transmission intermediate frequency filter used in the wireless communication devices shown in the fourth and fifth embodiments described above.

Fig. 7 is a block diagram showing the configuration of an integrated circuit in a seventh embodiment of the wireless communication device of the present invention.

FIG. 8 is used to illustrate the frequency structure in the embodiment of the present invention.

FIG. 9 is a block diagram showing the configuration of a conventional wireless communication device.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, the same reference numerals denote the same or corresponding parts.

The first embodiment of the wireless communication device of the present invention shown in FIG. 1 is the first digital communication system that can selectively use the first communication frequency band and the same as using the second communication frequency band lower than the frequency of the first frequency band. An embodiment of the second digital communication system of the modulated signal method.

In FIG. 1 , an antenna 1 is an antenna capable of transmitting and receiving communication signals in any one of a first communication frequency band and a second communication frequency band. The operation of the receiving system will be described. In the first communication mode, the signal received by the antenna 1 is demultiplexed by the antenna duplexer 2, input to the low-noise amplifier 3A to be amplified, passed through the channel switch 21 from the band-pass filter (not shown), and input to the Down frequency converter 4. Here, it is mixed with the RF local signal for the first communication frequency band, and converted into a receiving intermediate frequency.

Next, through the reception intermediate frequency filter 5 that only takes out the desired signal, it is amplified to a predetermined signal level by the reception intermediate frequency variable gain amplifier 6, and mixed with the local signal for quadrature demodulation in the quadrature demodulator 8 frequency, it becomes the received baseband composite signal, performs appropriate filter processing, A/D conversion processing, and inputs it to the modulation and demodulation receiving unit.

On the other hand, in the second communication mode, the signal received by the antenna 1 is demultiplexed by the antenna duplexer 2, input to the low-noise amplifier 3, passed through the channel switch 21 from the band-pass filter (not shown), and input to the step-down frequency converter 4. Here, it is mixed with the RF local signal of the second communication frequency band, and frequency-converted to the same receiving intermediate frequency as that of the first communication mode above.

Since the subsequent processing is the same as that in the first communication mode, processing circuits after the reception intermediate frequency filter 5 are shared between the two communication modes.

In the above operation, the RF local signals for the first and second communication bands are generated by k-dividing and l-frequency-dividing the VCO oscillation output of the common RF local frequency synthesizer 17 by the variable frequency divider 22 .

When the transmission system is in operation, in the first and second communication modes, the transmission baseband complex signal input from the modem transmission unit (not shown) is compared with the local signal for quadrature modulation in the quadrature modulator 11. Mixing, frequency conversion to send intermediate frequency. After the transmission intermediate frequency signal is amplified to a desired level by the transmission intermediate frequency variable gain amplifier 12, spurious components and noise components outside the desired frequency band are removed by the transmission intermediate frequency filter 13. Here, although the transmission intermediate frequency in the first communication mode and the transmission intermediate frequency in the second communication mode are different, they have an integer ratio n:m relationship. Therefore, the VCO oscillation output of the common quadrature modulation local frequency synthesizer 20 is frequency-divided by m in the first communication mode by the variable frequency divider 23 for the quadrature modulation local signal, and in the second communication mode Generated by dividing by n.

In the first communication mode, the transmission intermediate frequency signal is input to the upconverter 15A through the channel switch 14, mixed with the RF local signal for the first communication frequency band, and converted to the transmission frequency of the first communication frequency band. Then, the signal is amplified to a desired level by the power amplifier 16A through a band-pass filter and a driver amplifier, and then transmitted from the antenna 1 through the antenna duplexer 2 .

In the second communication mode, the transmission intermediate frequency signal is input to the upconverter 15B through the channel switch 14, mixed with the RF local signal for the second communication frequency band, and converted to the transmission frequency of the second communication frequency band. Then, the signal is amplified to a desired level by the power amplifier 16B through a band-pass filter and a driver amplifier, and then transmitted from the antenna 1 through the antenna duplexer 2 .

The relationship between the respective frequencies will be described using FIG. 8 .

Here, each frequency is defined as follows.

Downlink frequency of the 1st communication frequency band: FR1

Downlink frequency of the second communication band: FR2

Uplink frequency of the first communication frequency band: FT1=FR1-D1

Uplink frequency of the second communication frequency band: FT2=FR2-D2

RF native frequency synthesizer output frequency: F_VCO

RF local signal frequency for the first communication frequency band: L01=F_VCO/k

RF local signal frequency for the second communication frequency band: L02=F_VCO/l

Wherein, D1 and D2 are the frequency intervals of transmitting and receiving in each communication system, which are taken as positive values.

In FIG. 8 , the local frequency is on the upper side for the first communication frequency band, whereas the local frequency is lower for the second communication frequency band. However, in the present invention, the method of selecting the local frequency is not necessarily limited to the above.

Here, the receiving intermediate frequency becomes

F-VCO/k-FR1＝FR2-F_VCO/1 (1)

The receiving intermediate frequency in the first communication mode and the receiving intermediate frequency in the second communication mode start from the condition that the relationship of the integer ratio n:m becomes

m{F_VCO/k-(FR1-D1)}=

n{(FR2-D2)-F_VCO/l} (2)

Among them, since there are 5 unknowns k, l, m, n, and F_VCO, they cannot be determined at the same time. However, from the given frequency conditions FR1, FR2, FT1, and FT2 of the two communication systems, each unknown number can be obtained as minimal combination.

As above, due to

(A) RF native frequency synthesizer sharing one system in two communication modes

(B) The receiving IF filter and the receiving IF variable gain amplifier of the same system are shared in two communication modes

(C) The oscillation frequency of the oscillator that generates the local signal for quadrature modulation and quadrature demodulation is fixed to the same frequency in both communication modes

Therefore, it is effective in terms of small size, light weight, and low price of the terminal.

FIG. 2 shows the configuration of a second embodiment of the wireless communication device of the present invention. The wireless communication device of this embodiment is an example of a first digital communication system capable of selectively using a first communication frequency band and a second communication system of a second communication frequency band of a lower frequency and a different modulation signal method than that. Here, the AMPS system in the United States is assumed as the second communication system.

In this case, since the signal modulation method, that is, the occupied frequency bandwidth of the received signal differs between the first and second communication modes, it is not possible to share the reception IF filter as in the first embodiment. Therefore, in the second embodiment, the output of the down-converter 4 is switched with the channel selector switch 9, the same processing as that of the first embodiment is implemented in the first communication mode, and the AMPS receiving intermediate frequency is used in the second communication mode. The filter 5C is input to the AMPS receiving baseband unit after performing predetermined frequency conversion, amplification, and FM detection processing in the AMPS receiving intermediate frequency unit 10 .

For the transmission system, in the second embodiment, in any mode of the first communication mode and the second communication mode, the baseband composite signal is input from the modem transmission unit to the quadrature modulator 11, and the subsequent The processing is the same as that of the first embodiment.

According to the second embodiment, even when different signal modulation schemes are used in the first communication frequency band and the second communication frequency band, the advantages (A) and (C) described in the first embodiment can be enjoyed.

Next, FIG. 3 shows the configuration of a third embodiment in which the process of transmitting and receiving AMPS signals in the above-mentioned second embodiment is modified. The third embodiment is different from the second embodiment in the following two points.

The first point, on the receiving side, after passing through the AMPS receiving intermediate frequency filter 5C, the circuit through the channel switching switch 24 to input to the receiving intermediate frequency variable gain amplifier 6 and quadrature demodulator 8 is shared with the first communication mode .

The second point, on the sending side, the AMPS transmission signal is not a baseband composite FM signal, but the signal before FM modulation is input to the frequency control input terminal of the VCO constituting the local frequency synthesizer 20 for quadrature modulation, so that the oscillation frequency Offset added to FM modulation.

Various processing methods for transmitting and receiving AMPS signals in the second and third embodiments are not limited to combinations thereof, and may be changed. Even if any combination method is selected, the advantages (A) and (C) described in the first embodiment can be enjoyed.

Furthermore, the second and third embodiments also have the first digital communication system that can selectively use the first communication frequency band, and the second digital communication system that has a lower frequency than that and has the same signal modulation method in the second communication frequency band. The system and the wireless communication device of the third communication system having a different signal modulation method in the second communication frequency band can be directly used without adding any new structure. This is because the structure of the first embodiment is included in the structures of these embodiments. Therefore, the advantages of (A), (B), and (C) described in the first embodiment can be enjoyed.

In FIG. 4, as a fourth embodiment of the wireless communication device of the present invention, three PCS-CDMA systems, a cellular CDMA system with an 800 MHz frequency band, and a dual-frequency cellular AMPS system that can selectively use the 1900 MHz frequency band used in the United States are shown. A specific configuration example of a mobile communication terminal of such a communication system.

In FIG. 4, the received AMPS signal processing uses the method of the above-mentioned second embodiment, and the transmitted AMPS signal processing uses the method of the above-mentioned third embodiment.

PCS-CDMA system

Downlink frequency: 1930.00-1989.95MHz

Uplink frequency: 1850.00-1909.95MHz

Cellular CDMA system and AMPS system

Downlink frequency: 869.04-893.97MHz

Uplink frequency: 824.04-848.97MHz

Based on such a frequency relationship and the above formulas (1) and (2), the combination having the minimum value among the combinations of frequency division numbers k, l, m, and n of the respective local signals is the following combination.

k=1

l=3

m=1

n=2

At this time, the frequency (unit: MHz) of each part is as follows.

[Receiving RF frequency] PCS: 1930.00-1989.95

Cellular: 869.04-893.97

[RF local frequency] PCS: 2100.00-2159.95

Cellular: 699.04-723.97

[RF-VCO oscillation frequency] PCS: 2100.00-2159.95

Cellular: 2097.12-2171.91

[Receiving IF frequency] PCS: 170.0

Cellular: 170.0

[Quadrature demodulation local VCO oscillation frequency] PCS: 170.0

Cellular: 170.0

[Sending IF frequency] PCS: 250.0

Cellular: 125.0

[Quadrature modulation local VCO oscillation frequency] PCS: 250.0

Cellular: 250.0

In the fourth embodiment, the generation of the quadrature local signals in the quadrature demodulator 8 and the quadrature modulator 11 assumes that a 90-degree phase shifter using an analog circuit composed of resistors and capacitors, etc., is used as another quadrature The generation method of the local signal is shown in the structure of the fifth embodiment of FIG. 5 by using the quadrature signal generated in the process of dividing the frequency signal of 2 times or 4 times the frequency of the desired frequency into the desired frequency. Case. In this case, the frequency (unit: MHz) consists of

m=2

n=4

[Receiving IF Frequency] PCS: 1930.00～1989.95

Cellular: 869.04～893.97

[RF local frequency] PCS: 2100.00～2159.95

Cellular: 699.04～723.97

[RF-VCO oscillation frequency] PCS: 2100.00～2159.95

Cellular: 2097.12～2171.91

[Receiving IF frequency] PCS: 170.0

Cellular: 170.0

[Quadrature modulation local VCO oscillation frequency] PCS: 340.0

Cellular: 340.0

[Sending IF frequency] PCS: 250.0

Cellular: 125.0

[Quadrature modulation local VCO oscillation frequency] PCS: 500.0

Cellular: 500.0

In the fourth and fifth embodiments, the IF filter 13 is commonly transmitted regardless of the PCS system or the cellular system. FIG. 6 shows frequency characteristics of filters for enabling such sharing as a sixth embodiment.

First, the passband must include 125MHz and 250MHz. Secondly, for the stop band, it is important to mix the high-order harmonics of the transmitted intermediate frequency signal and the high-order harmonics of the RF local signal, so that no spurious frequencies are generated within the transmission frequency band of each system or near the system, and it is necessary to determine the stop band. band to prevent spurious frequencies from occurring. Higher harmonics have higher strength as their order is smaller. Therefore, considering the combination of small orders, the 5th harmonic of the transmission intermediate frequency signal in the cellular mode and the 2nd harmonic of the RF local signal occur near the intermediate frequency band of the cell. wave frequency difference. Therefore, it is necessary to use a filter to block 625 MHz, which is the fifth harmonic of the transmission intermediate frequency signal in the cellular system. The attenuation is more than 20dB.

Next, a seventh embodiment of the wireless communication device of the present invention will be described. Since it is desired to divide the output of the RF local frequency synthesizer 17 in the first to third embodiments by k and l, the variable frequency divider 22 and the output of the local frequency synthesizer 20 for quadrature modulation by m The variable frequency divider 23 for frequency division by n is included in the integrated circuit constituting the wireless unit. Therefore, the structure of the integrated circuit including these variable frequency dividers 22 and 23 is shown in FIG. 7 .

The integrated circuit 25 of FIG. 7 includes variable frequency dividers 22, 23, RF local frequency synthesizer 17, and part of the PLL circuit of the local frequency synthesizer 20 for quadrature modulation, namely a phase frequency comparator (PFC) and a divider. frequency converter.

Receive a signal (mode signal in the figure) indicating communication in a certain communication frequency band supplied from the control circuit of the wireless communication device, so that the variable frequency division that divides the output of the RF local frequency synthesizer 17 can be switched. The frequency division ratios k and l of the device 22 and the frequency division ratios m and n of the variable frequency divider 23 for dividing the output of the local frequency synthesizer 20 for quadrature modulation. By using this integrated circuit 25, the wireless communication device of the present invention can be easily configured.

As described above, the wireless communication device of the present invention is a wireless communication device in which the number of components is reduced as much as possible by devising a frequency configuration, and has a wireless communication system capable of selectively using communication bands of different frequencies. Device miniaturization, light weight and low price effect.

Claims (14)

1. A wireless communication device capable of selectively using a first communication mode using a first communication frequency band for communication, and using substantially the same communication mode as the first communication mode in a second communication frequency band lower in frequency than the first communication frequency band. Communication in one of the second communication modes in which the modulated signal method communicates has the following functions, Wherein, in the first communication mode, the receiving unit uses the first local signal to down-convert the received signal of the first communication frequency band to the first received intermediate frequency, and in the second communication mode, uses the received signal of the second communication frequency band to use The second local signal is down-converted to the second receiving intermediate frequency, In the first communication mode, the transmitting unit up-converts the first transmission intermediate frequency signal to the above first communication frequency band using the first local signal, and in the second communication mode, uses the second transmission intermediate frequency signal to use the second local signal. The frequency of the machine signal is up-converted to the above-mentioned second communication frequency band, The above-mentioned first and second transmission intermediate frequency signals are generated by performing quadrature modulation on the transmission baseband composite signal frequency signal using the third and fourth local signals, respectively, It is characterized by: Above-mentioned the 1st and the 2nd local signal use the output signal of the 1st oscillator and have carried out the signal of k frequency division and l frequency division (k, l is a positive integer) respectively with the 1st variable frequency divider, Setting the above-mentioned first receiving intermediate frequency and the above-mentioned second receiving intermediate frequency to be equal, Setting the above-mentioned first transmission intermediate frequency and the above-mentioned second transmission intermediate frequency to an integer ratio n:m (m, n is a positive integer), As the third and fourth local signals, signals obtained by m-dividing and n-frequency-dividing the output signal of the second oscillator are used, respectively, by the second variable frequency divider. 2. The wireless communication device according to claim 1, characterized in that: In the first and second communication modes, the filters and amplifiers for passing the first and second reception intermediate frequency signals are shared. 3. The wireless communication device according to claim 1 or claim 2, characterized in that: In the first and second communication modes, the amplifiers and filters for passing the first and second transmission intermediate frequency signals are shared. 4. A wireless communication device capable of selectively using a first communication mode using a first communication frequency band for communication, and using a communication mode different from the first communication mode in a second communication frequency band lower in frequency than the first communication frequency band. Communication in one of the second communication modes in which communication is performed by means of modulated signals has the following functions, Wherein, in the above-mentioned first communication mode, the receiving unit down-converts the received signal of the first communication frequency band to the first receiving intermediate frequency by using the first local signal, and converts the received signal of the second communication frequency band to the first receiving intermediate frequency in the above-mentioned second communication mode. The signal uses the second local signal to down-convert to the second receiving intermediate frequency, In the above-mentioned first communication mode, the transmitting unit up-converts the first transmission intermediate frequency signal to the above-mentioned first communication frequency band using the above-mentioned first local signal, and in the above-mentioned second communication mode, uses the second transmission intermediate frequency signal to use the above-mentioned first 2 The local signal is up-converted to the above-mentioned second communication frequency band, The above-mentioned first and second transmission intermediate frequency signals are generated by performing quadrature modulation on the transmission baseband composite signal frequency signal using the third and fourth local signals, respectively, It is characterized by: Above-mentioned the 1st and the 2nd local signal use the output signal of the 1st oscillator and have carried out the signal of k frequency division and l frequency division (k, l is a positive integer) respectively with the 1st variable frequency divider, Setting the above-mentioned first receiving intermediate frequency and the above-mentioned second receiving intermediate frequency to be equal, Setting the above-mentioned first transmission intermediate frequency and the above-mentioned second transmission intermediate frequency to an integer ratio n:m (m, n is a positive integer), As the third and fourth local signals, signals obtained by m-dividing and n-frequency-dividing the output signal of the second oscillator are used, respectively, by the second variable frequency divider. 5. The wireless communication device according to claim 4, characterized in that: In the first and second communication modes, the amplifiers and filters for passing the first and second transmission intermediate frequency signals are shared. 6. A wireless communication device capable of selectively using a first communication mode using a first communication frequency band for communication, and using a communication mode different from the first communication mode in a second communication frequency band lower in frequency than the first communication frequency band. Communication in one of the second communication modes in which communication is performed by means of modulated signals has the following functions, Wherein, in the first communication mode, the receiving unit uses the first local signal to down-convert the received signal of the first communication frequency band to the first received intermediate frequency, and in the second communication mode, uses the received signal of the second communication frequency band to use The second local signal is down-converted to the second receiving intermediate frequency, In the first communication mode, the transmitting unit up-converts the first transmission intermediate frequency signal to the above first communication frequency band using the first local signal, and in the second communication mode, uses the second transmission intermediate frequency signal to use the second local signal. The frequency of the machine signal is up-converted to the above-mentioned second communication frequency band, The above-mentioned first transmission intermediate frequency signal is generated by performing quadrature modulation on the transmission baseband composite signal frequency signal using the third and fourth local signals respectively, and the above-mentioned second transmission intermediate frequency signal is obtained by performing FM modulation on the fourth local signal, It is characterized by: Above-mentioned the 1st and the 2nd local signal use the output signal of the 1st oscillator and have carried out the signal of k frequency division and l frequency division (k, l is a positive integer) respectively with the 1st variable frequency divider, Setting the above-mentioned first receiving intermediate frequency and the above-mentioned second receiving intermediate frequency to be equal, Setting the above-mentioned first transmission intermediate frequency and the above-mentioned second transmission intermediate frequency to an integer ratio n:m (m, n is a positive integer), As the third and fourth local signals, signals obtained by m-dividing and n-frequency-dividing the output signal of the second oscillator are used, respectively, by the second variable frequency divider. 7. The wireless communication device according to claim 6, characterized in that: In the first and second communication modes, the amplifiers and filters for passing the first and second transmission intermediate frequency signals are shared. 8. A wireless communication device capable of selectively using a first communication mode using a first communication frequency band for communication, and using substantially the same communication mode as the first communication mode in a second communication frequency band lower in frequency than the first communication frequency band. The second communication mode in which communication is performed using a modulated signal method in the above-mentioned second communication frequency band, and communication is performed in any one of the third communication modes in which communication is performed using a modulated signal method different from that in the first communication mode, and has the following function, Wherein, in the first communication mode, the receiving unit down-converts the received signal of the first communication frequency band to the first receiving intermediate frequency using the first local signal, and converts the signal of the second communication frequency band to the first receiving intermediate frequency in the second and third communication modes. The receiving signal uses the second local signal down-converted to the second receiving intermediate frequency, In the first communication mode, the transmitting unit up-converts the first transmission intermediate frequency signal to the above first communication frequency band using the first local signal, and in the second and third communication modes, uses the second transmission intermediate frequency signal to use the above The frequency of the second local signal is up-converted to the above-mentioned second communication frequency band, The above-mentioned first and second transmission intermediate frequency signals are generated by performing quadrature modulation on the transmission baseband composite signal frequency signal using the third and fourth local signals, respectively, It is characterized by: Above-mentioned the 1st and the 2nd local signal use the output signal of the 1st oscillator and have carried out the signal of k frequency division and l frequency division (k, l is a positive integer) respectively with the 1st variable frequency divider, Setting the above-mentioned first receiving intermediate frequency and the above-mentioned second receiving intermediate frequency to be equal, Setting the above-mentioned first transmission intermediate frequency and the above-mentioned second transmission intermediate frequency to an integer ratio n:m (m, n is a positive integer), As the third and fourth local signals, signals obtained by m-dividing and n-frequency-dividing the output signal of the second oscillator are used, respectively, by the second variable frequency divider. 9. The wireless communication device according to claim 8, characterized in that: In the first and second communication modes, the filters and amplifiers for passing the first and second reception intermediate frequency signals are shared. 10. The wireless communication device according to claim 8 or claim 9, characterized in that: A configuration is adopted in which amplifiers and filters for passing the first and second transmission intermediate frequency signals are shared in the first, second, and third communication modes. 11. A wireless communication device capable of selectively using a first communication mode using a first communication frequency band for communication, and using substantially the same communication mode as the first communication mode in a second communication frequency band lower in frequency than the first communication frequency band. The second communication mode in which communication is performed using a modulated signal method in the above-mentioned second communication frequency band, and communication is performed in any one of the third communication modes in which communication is performed using a modulated signal method different from that in the first communication mode, and has the following function, Wherein, in the first communication mode, the receiving unit down-converts the received signal of the first communication frequency band to the first receiving intermediate frequency using the first local signal, and converts the signal of the second communication frequency band to the first receiving intermediate frequency in the second and third communication modes. The receiving signal uses the second local signal down-converted to the second receiving intermediate frequency, In the first communication mode, the transmitting unit up-converts the first transmission intermediate frequency signal to the above first communication frequency band using the first local signal, and in the second and third communication modes, uses the second transmission intermediate frequency signal to use the above The frequency of the second local signal is up-converted to the above-mentioned second communication frequency band, In the first and second communication modes, the above-mentioned first and second transmission intermediate frequency signals are generated by performing quadrature modulation on the transmission baseband composite signal frequency signal using the third and fourth local signals, respectively, In the third communication mode, the above-mentioned second transmission intermediate frequency signal is obtained by performing FM modulation on the fourth local signal, It is characterized by: Above-mentioned the 1st and the 2nd local signal use the output signal of the 1st oscillator and have carried out the signal of k frequency division and l frequency division (k, l is a positive integer) respectively with the 1st variable frequency divider, Setting the above-mentioned first receiving intermediate frequency and the above-mentioned second receiving intermediate frequency to be equal, Setting the above-mentioned first transmission intermediate frequency and the above-mentioned second transmission intermediate frequency to an integer ratio n:m (m, n is a positive integer), As the third and fourth local signals, signals obtained by m-dividing and n-frequency-dividing the output signal of the second oscillator are used, respectively, by the second variable frequency divider. 12. The wireless communication device according to claim 11, characterized in that: A filter and an amplifier for passing the first and second reception intermediate frequency signals are shared in the first and second communication modes. 13. The wireless communication device according to claim 11 or claim 12, characterized in that: A configuration is adopted in which amplifiers and filters for passing the first and second transmission intermediate frequency signals are shared in the first, second, and third communication modes. 14. An integrated circuit, characterized in that: At least a part of the PLL circuit for oscillating the first oscillator at a predetermined frequency is installed inside, and the output signal of the first oscillator is divided by k and l (k, l are positive integers) and then output. The first variable frequency divider is used to make the second oscillator oscillate at least a part of the PLL circuit at a predetermined frequency, and divides the output signal of the second oscillator by m frequency division and n frequency division (m, n is a positive integer) and outputs the second variable frequency divider, and has the function of selecting the frequency division number according to the communication mode.

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