JPH06284039A - Radio communication equipment - Google Patents

Abstract

PURPOSE:To evade the spurious response of a receiver without interrupting the reduction in size, weight and cost of this radio communication equipment by adjusting the resonance point of a resonator element in a filter. CONSTITUTION:The interruption area of a filter 6 is determined by the resonance point of a resonator element 7 to be changed in accordance with the capacitance value of a fixed capacitor 8 and a variable capacitance element 11. Thereby a band elimination filter for interfering wave (fTX-DELTAf) corresponding to optional transmission frequency f can be formed by changing control voltage impressed between the electrodes of the element 11 to control its capacitance. Even when an interrupting wave with the frequency (fTX-DELTAf) is received by an antenna 1, the generation of spurious response on the receiver side can be evaded without generating a component with frequency fTX as a mutual modulation component in a power amplifier 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a portable telephone or a cordless telephone in which an antenna is connected to a power amplifier for transmission and a high frequency amplifier for reception via a duplexer to communicate using different frequencies for transmission and reception. Etc. regarding a wireless communication device.

[0002]

2. Description of the Related Art FIG. 7 is a block diagram showing a configuration of an antenna peripheral portion of a conventional wireless communication apparatus. In the figure, 1 is an antenna shared by both transmission and reception, 2 is a power amplifier for transmission that amplifies the power of a transmission signal transmitted from this antenna 1, and 3 is reception received by this antenna 1. It is a high frequency amplifier for reception that performs high frequency amplification of a signal. Reference numeral 4 is a duplexer for guiding the transmission signal power-amplified by the power amplifier 2 to the antenna 1 and guiding the reception signal received by the antenna 1 to the high-frequency amplifier 3.

Next, the operation will be described. In the following description, the case where the reception frequency f _RX is higher than the transmission frequency f _TX will be described.

When this radio communication device is communicating, the antenna 1 receives a disturbing signal whose frequency is f _TX -Δf (where Δf is the difference between the reception frequency f _RX and the transmission frequency f _TX ). In this case, as shown in FIG. 8, a frequency f _RX equal to the reception frequency is generated as an intermodulation (hereinafter referred to as IM) component of the power amplifier 2 for transmission, and a spurious response is generated in the receiver of the wireless communication device. To do.

Conventionally, in order to avoid the occurrence of such spurious response in the receiving section of the wireless communication device, the transmitting side of the duplexer 4 has a bandpass structure, or as shown in FIG. By placing the isolator 5 between the duplexers 4,
This has been dealt with by preventing an interfering signal having a frequency of f _TX -Δf from flowing into the power amplifier 2.

[0006]

Since the conventional radio communication device is configured as described above, in order to avoid the spurious response of the receiver which occurs when the interfering signal of the frequency f _TX -Δf is received, When the duplexer 4 has a bandpass configuration, the shape of the duplexer 4 becomes large, and when the isolator 5 is inserted, not only a space for disposing the isolator 5 is required but also a transmission wave loss is generated. Therefore, there is a problem in that it hinders downsizing, weight reduction, and power consumption reduction of the wireless communication device.

The present invention has been made to solve the above problems, and spurious response of a receiver due to a transmitted IM wave component can be achieved without hindering downsizing, weight reduction and power consumption reduction of the device. It is an object of the present invention to obtain a wireless communication device that can avoid.

[0008]

According to a first aspect of the present invention, there is provided a radio communication device, wherein a resonance element, its resonance element and a variable capacitance element for adjusting the resonance point of this resonance element are provided at a connection point between a power amplifier and a duplexer. The control of the control unit based on the command, which is set by the command unit and whose content is stored in the storage unit, by connecting the filter including the It is decided by.

According to a second aspect of the present invention, there is provided a wireless communication device in which a filter including a resonance element and a variable capacitance element for adjusting a resonance point of the resonance element is connected to a connection point between a duplexer and a high frequency amplifier. Is.

Further, in the wireless communication apparatus according to the invention of claim 3, the setting of the command for determining the control voltage is performed by an external input through serial communication.

[0011]

According to the variable voltage source of the present invention, the variable capacitance element of the filter connected to the connection point of the power amplifier and the duplexer is set by the instruction unit and the contents are stored in the storage unit. By applying a control voltage of a voltage value determined by the control of the control unit based on the above, and adjusting the resonance point of the resonance element of the filter, it is possible to reduce the size, weight and power consumption of the device. To realize a wireless communication device capable of avoiding spurious response in a receiver.

According to the second aspect of the present invention, in the radio communication device, the filter whose resonance point of the resonance element is adjusted by the variable capacitance element is connected to the connection point of the duplexer and the high frequency amplifier, so that the frequency f _RX is reduced. It is also possible to support when the signal that causes spurious response is within the reception band.

In the wireless communication device according to the invention of claim 3, the command for determining the control voltage is input from the outside by serial communication to automate the setting of the command for adjusting the resonance point of the filter. It is possible.

[0014]

EXAMPLES Example 1. Embodiment 1 of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of the invention of claim 1. In the figure, 1 is an antenna, 2 is a power amplifier for transmission, 3 is a high frequency amplifier for reception, 4
Is a duplexer, which is the same as or equivalent to those of the conventional one denoted by the same reference numeral in FIG. 7, and therefore detailed description thereof will be omitted.

Further, 6 is a filter connected to the connection point of the power amplifier 2 and the duplexer 4, 7 is a resonance element such as a dielectric resonator constituting the filter 6, and 8 and 9 are also fixed. The capacitors 10 are inductors. Reference numeral 11 is a variable capacitance element such as a varicap that finely adjusts the resonance point of the resonance element 7 by changing the value of the capacitance according to the voltage applied to the electrode.

Further, 12 is an A / D converter as a variable voltage source for generating a control voltage applied to the variable capacitance element 11 of the filter 6, and 13 is an inductor for the control voltage output from the A / D converter 12. A resistor applied to the variable capacitance element 11 via 10. 14 is this A
A CPU as a control unit that controls the voltage value of the control voltage output from the / D converter 12, 15 is the CPU 1
4 is a keypad as an instruction unit for setting an instruction to control the A / D converter 12, and 16 is a storage unit for storing the contents of the instruction set by the keypad 15. Note that the CPU 14, the keypad 15, the storage unit 16, and the like are shared by those provided in the wireless communication device.

Next, the operation will be described. Filter 6
Is a fixed capacitor 8 in which a resonant element 7 is connected in series.
The variable capacitance element 11 is connected in parallel to form a band elimination filter, and the pass band thereof is determined by the resonance point of the fixed capacitor 8 and the resonance element 7 that changes according to the capacitance value of the variable capacitance element 11. Therefore,
If the capacitance is controlled by changing the control voltage applied between the electrodes of the variable capacitance element 11, a band elimination filter for the interference wave f _TX −Δf with respect to an arbitrary transmission frequency f _TX can be formed. it can. As a result, even when the interference wave having the frequency f _TX −Δf is received by the antenna 1, the component of the frequency wave f _RT is not generated as the IM component of the power amplifier 2, and the spurious response on the receiver side is avoided. It becomes possible.

The storage unit 16 stores in advance the content of the command set for each channel by the keypad 15. The CPU 14 reads the content of the command corresponding to the channel from the storage unit 16 and sends the digital data indicating the voltage value of the control voltage to be output to the A / D converter 12. The A / D converter 12 converts the received digital data into an analog voltage, and applies it as a control voltage from the resistor 13 to the variable capacitance element 11 via the inductor 10. Here, the A / D converter 12
If an 8-bit configuration is used as the CPU 14 and the effective applied voltage of the variable capacitance element 11 is V, V
The voltage applied to the variable capacitance element 11 can be variably controlled in step / 256.

Next, a method of setting the instruction in the storage unit 16 will be described. Here, when the filter 6 is incorporated in the housing of the wireless communication device, the resonance point may change depending on whether or not there is a shield member at an adjacent position, so that the same as when the wireless communication device is used. It is necessary to set the instruction under the condition of. FIG. 3 is a block diagram showing a method of setting this command. In the figure, 20 is a signal generator that generates a signal wave for each channel, and 21 is a signal generator that generates an interference wave. 22 is these signal generators 20 and 2
The combiner 23 combines the outputs of 1 and 23.
2 is a circulator connected to 2, and 24 is a power meter branched and connected by the circulator 23. Reference numeral 25 is an attenuator connected to the circulator 23, 26 is the wireless communication device connected to the attenuator 25, and 27 is a signal plus noise plus distortion versus noise for measuring the amount of spurious response of the wireless communication device 26. It is a positive strain ratio meter (hereinafter referred to as SINAD meter).

First, the signal generator 20 generates a signal of frequency f _RX , and the signal generator 21 generates an interference wave of frequency f _TX -Δf. These signals and interfering waves are combined by the coupler 2
The signals are combined in 2, and input to the wireless communication device 26 via the circulator 23 and the attenuator 25. Wireless communication device 26
Then, while changing the command set from the keypad 15, the amount of spurious response is measured by the SIDAN meter 27 each time, and the content of the command when the spurious response becomes the minimum is stored in the storage unit 16. This operation is performed for each channel, and the content of the instruction that minimizes the spurious response for all channels is stored in the storage unit 16.
Set to each.

Example 2. Further, although the case where the filter 6 is connected to the connection point of the power amplifier 2 for transmission and the duplexer 4 has been described in the first embodiment, it is connected to the connection point of the duplexer 4 and the high frequency amplifier 3 for reception. You may do it. FIG. 4 is a block diagram showing an embodiment of such an invention described in claim 2, and the same reference numerals as those of the corresponding portions of the embodiment 1 shown in FIG. To do. In this way, by connecting the filter 4 to the connection point between the duplexer 4 and the high-frequency amplifier 3 for reception, in the receiver of the wireless communication device,
Even in the case where the signal causing the spurious response of the frequency f _RX is within the reception band, it is possible to deal with it in the same manner as in the case of the first embodiment.

Example 3. Further, in each of the above embodiments, the instruction is set by the keypad 15, but the instruction may be set by serial communication from the outside. FIG. 5 is a block diagram showing an embodiment of such an invention described in claim 3, in which 17 is a C as a control unit.
The PU 14 is an interface unit that acts as a command unit for setting a command for controlling the A / D converter 12 serving as a variable voltage source. The PU 14 interfaces a command input from the outside by serial communication and inputs it to the CPU 14. To do. Therefore, if the signal serially transmitted from the outside can be processed by the CPU 14 as it is, the command unit (interface unit) 17 may be a simple connector.

As described above, when the instruction can be set by the serial communication from the outside, the storage of the content of the instruction in the storage unit 16 can be automated. FIG. 6 is a block diagram showing the automatic instruction setting method. In the figure, 28 is a personal computer (hereinafter referred to as a personal computer) for automatically setting instructions. Note that, in FIG. 6, the respective devices shown in FIG. 3 connected to the wireless communication device 26 via the attenuator are omitted.

In this case as well, the composite signal of the signal of frequency f _RX and the interfering wave of frequency f _TX -Δf is input to the radio communication device 26 for each channel. Then, the personal computer 28 sends a command for setting to the interface section 17 of the wireless communication device 26 by serial communication, and while changing the command, the SID
The amount of spurious response measured by the AN meter 27 is read. The personal computer 28 instructs the CPU 14 of the wireless communication device 26 to store the content of the command when the spurious response becomes the minimum in the storage unit 16. Such an operation is performed for each channel, and the content of the instruction that minimizes the spurious response is automatically set in the storage unit 16 for all channels.

[0025]

As described above, according to the first aspect of the present invention, the variable capacitance element of the filter connected to the connection point between the power amplifier and the duplexer is set in the command section, and its contents are stored in the storage section. Since the control voltage of the voltage value determined based on the command stored in is applied to adjust the resonance point of the resonance element of the filter, the device can be made smaller, lighter and consume less power. There is an effect that a wireless communication device capable of avoiding a spurious response in a receiver can be obtained without hindrance.

According to the second aspect of the invention, since the filter in which the resonance point of the resonance element is adjusted by the variable capacitance element is connected to the connection point between the duplexer and the high frequency amplifier, the frequency f _RX is increased. Even if the signal that causes the spurious response is within the reception band, it is possible to cope with the situation.

Further, according to the invention of claim 3, since the command for adjusting the resonance point of the filter is inputted from the outside by serial communication, the setting of the command is automatically performed by a personal computer or the like. There is an effect that can be done.

[Brief description of drawings]

FIG. 1 is a block diagram showing a main part of a wireless communication device according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram showing the characteristics of the filter in the above embodiment.

FIG. 3 is a block diagram for explaining an instruction setting method in the above embodiment.

FIG. 4 is a block diagram showing a main part of a wireless communication device according to a second embodiment of the present invention.

FIG. 5 is a block diagram showing a main part of a wireless communication device according to a third embodiment of the present invention.

FIG. 6 is a block diagram for explaining an instruction setting method in the above embodiment.

FIG. 7 is a block diagram showing a main part of a conventional wireless communication device.

FIG. 8 is an explanatory diagram showing a transmission IM component of a conventional wireless communication device.

FIG. 9 is a block diagram showing a main part of another conventional wireless communication device.

[Explanation of symbols]

 1 Antenna 2 Power Amplifier 3 High Frequency Amplifier 4 Duplexer 6 Filter 7 Resonant Element 11 Variable Capacitance Element 12 Variable Voltage Source (A / D Converter) 14 Control Section (CPU) 15 Command Section (Keypad) 16 Memory Section 17 Command Section (Interface) Part)

[Procedure amendment]

[Submission date] July 23, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0016

[Correction method] Change

[Correction content]

Further, 12 is a variable voltage source for generating a control voltage applied to the variable capacitance element 11 of the filter 6.
D / A converter , 13 is this D / A converter
A resistor to be applied to the variable capacitance element 11 and the control voltage output of the motor 12 via the inductor 10. 14 is this D
A CPU as a control unit that controls the voltage value of the control voltage output from the A / A converter 12, 15 is the CPU 1
Reference numeral 4 is a keypad as an instruction unit for setting an instruction to control the D / A converter 12, and reference numeral 16 is a storage unit for storing the contents of the instruction set by the keypad 15. Note that the CPU 14, the keypad 15, the storage unit 16, and the like are shared by those provided in the wireless communication device.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0018

[Correction method] Change

[Correction content]

The storage unit 16 stores in advance the content of the command set for each channel by the keypad 15. The CPU 14 reads the content of the command corresponding to the channel from the storage unit 16 and sends the D / A converter 12 digital data indicating the voltage value of the control voltage to be output. The D / A converter 12 converts the received digital data into an analog voltage, and applies it as a control voltage from the resistor 13 to the variable capacitance element 11 via the inductor 10. Here, the D / A converter 12
If an 8-bit configuration is used as the CPU 14 and the effective applied voltage of the variable capacitance element 11 is V, V
The voltage applied to the variable capacitance element 11 can be variably controlled in step / 256.

[Procedure 3]

[Document name to be amended] Statement

[Name of item to be corrected] 0022

[Correction method] Change

[Correction content]

Example 3. Further, in each of the above embodiments, the instruction is set by the keypad 15, but the instruction may be set by serial communication from the outside. FIG. 5 is a block diagram showing an embodiment of such an invention described in claim 3, in which 17 is a C as a control unit.
The PU 14 is an interface unit that acts as a command unit for setting a command for controlling the D / A converter 12 as a variable voltage source, and inputs a command input from the outside by serial communication to the CPU 14. To do. Therefore, if the signal serially transmitted from the outside can be processed by the CPU 14 as it is, the command unit (interface unit) 17 may be a simple connector.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] Explanation of code

[Correction method] Change

[Correction content]

[Explanation of Codes] 1 Antenna 2 Power Amplifier 3 High Frequency Amplifier 4 Duplexer 6 Filter 7 Resonance Element 11 Variable Capacitance Element 12 Variable Voltage Source ( D / A Converter ) 14 Control Section (CPU) 15 Command Section (Keypad) 16 Storage Section 17 Command part (interface part)

[Procedure Amendment 5]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 1

[Correction method] Change

[Correction content]

[Figure 1]

Claims (3)

[Claims] 1. A wireless communication device in which a power amplifier for transmission and a high frequency amplifier for reception are connected to an antenna shared by transmission and reception via a duplexer, and communication is performed using different frequencies for transmission and reception. , A resonance element and a filter having a variable capacitance element that adjusts the resonance point of the resonance element by changing the electrostatic capacitance according to the applied voltage are connected to the connection point between the power amplifier and the duplexer. A variable voltage source that generates a control voltage to be applied to the variable capacitance element of the filter, a control unit that controls the value of the control voltage output by the variable voltage source, and a control unit that controls the variable voltage source. A wireless communication device comprising: a command unit for setting a command, and a storage unit for storing the content of the command set by the command unit. 2. A wireless communication device in which a power amplifier for transmission and a high frequency amplifier for reception are connected to an antenna shared by transmission and reception via a duplexer, and communication is performed using different frequencies for transmission and reception. A resonance element and a filter having a variable capacitance element that adjusts the resonance point of the resonance element by changing the electrostatic capacitance according to the applied voltage are connected to the connection point between the duplexer and the high-frequency amplifier. A variable voltage source that generates a control voltage to be applied to the variable capacitance element of the filter, a control unit that controls the value of the control voltage output by the variable voltage source, and a control unit that controls the variable voltage source. A wireless communication device comprising: a command unit for setting a command, and a storage unit for storing the content of the command set by the command unit. 3. The wireless communication device according to claim 1, wherein the command unit is an interface unit that interfaces a command input from the outside by serial communication and inputs the command to the control unit. .