JPH08146U - Wireless transmitter - Google Patents

Abstract

(57) [Summary] (Modified) [Purpose] An amplifier circuit has an amplifier and an attenuator, and P is placed between the transmission line of the attenuator and the ground so as to obtain matching.
In a wireless transmitter configured with an IN diode interposed, consistency is ensured, abnormal transmission does not occur, and the gain of amplification can be controlled. In addition, frequency characteristics can be obtained as ideal. To do so. [Configuration] PIN diodes 9, 10, 16, 17
Coils 11, 12, 18 for removing parasitic capacitance,
19 or microstrip lines are connected in parallel. [Effect] In the PIN diode, when the coil or the microstrip line is connected in parallel, the parasitic capacitance is removed, the ideal matching as designed is secured, and as a result, abnormal transmission does not occur, Further, the gain of amplification is as designed and controllable, and in addition, the frequency characteristic is as designed and obtained as ideal.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a wireless transmitter, and more particularly to a wireless transmitter in which a widening circuit includes an amplifying unit and an attenuating unit in order to widen an amplification width of an amplifying circuit.

[0002]

[Prior art]

 In a radio transmitter in which an amplification circuit includes an amplification unit composed of, for example, a transistor and the like, and an attenuation unit that attenuates a signal, conventionally, in order to obtain consistency between the amplification unit and the attenuation unit, the input unit and the output unit of the attenuation unit are used. It is known to interpose a PIN diode between the ground and the ground.

[0003]

[Problems to be solved by the device]

 A radio transmitter in which an amplifier circuit includes an amplifier and an attenuator, and a PIN diode is interposed between the input and the output of the attenuator and the ground, the PIN diode functions as a capacitor when operating. Since it has a parasitic capacitance, the matching actually obtained is not as designed, and as a result abnormal oscillation may occur. However, there is a problem that the frequency characteristic deviates from the design value and an ideal value cannot be obtained.

The present invention has been made in view of the above circumstances, and an amplifier circuit includes an attenuator and an amplifier, and provides matching between an input and an output of the attenuator and a ground. In a wireless transmitter configured with a PIN diode interposed, the PIN diode does not have parasitic capacitance during operation, and as a result, abnormal oscillation may occur during actual operation. In addition, the present invention provides a wireless transmitter in which the gain of the amplifier circuit is the theoretical value and sufficient control can be performed, and in addition, the frequency characteristics are as designed and ideal values are obtained. .

[0005]

[Means for Solving the Problems]

 In this invention, an amplifier circuit is composed of an amplifier and an attenuator, and a PIN diode for ensuring the matching between the amplifier and the attenuator is interposed between the transmission line of the attenuator and the ground. A wireless transmitter configured by connecting the PIN diode in parallel with a coil or a microstrip line for removing parasitic capacitance.

The detailed configuration is as follows: An oscillation circuit that oscillates a signal of a specific frequency by applying a voltage, a modulation circuit that modulates the amplitude of the signal from the oscillation circuit to a desired level, and a signal from the modulation circuit to a predetermined level. Amplifier circuit that amplifies so that the power becomes equal to the power of the amplifier, a filter circuit that removes unnecessary signals from the signal from the amplifier circuit, and a power supply that applies a predetermined voltage to the oscillator circuit, the modulation circuit, and the amplifier circuit. A circuit, the amplification circuit includes an amplification unit that amplifies the power of the input signal and an attenuator that attenuates the power of the input signal to a desired level, and the transmission line of the attenuation unit. A PIN diode is provided between the amplifier and the attenuator for matching between the amplifier and the attenuator, and a PIN or a microstrip line for removing the parasitic capacitance is added to the PIN diode. It is a wireless transmitter configured by connecting in parallel.

[0007]

[Action]

 The PIN diode for matching is connected in parallel with the coil or the microstrip line and does not generate parasitic capacitance.

[0008]

【Example】

 This invention will be described in detail based on the embodiment shown in FIGS. However, the present invention is not limited to this embodiment.

As shown in FIG. 1, the wireless transmitter 1 includes an oscillation circuit 2, a modulation circuit 3, an amplification circuit 4, a filter circuit 5, and a power supply means 6. The oscillator circuit 2 oscillates a signal of a specific frequency when a voltage is applied. The modulation circuit 3 modulates the amplitude of the signal from the oscillation circuit 2 to a desired level. The amplifier circuit 4 amplifies the signal from the modulation circuit 3 so as to have a predetermined power. The amplifier circuit 4 includes an attenuator 7 and an amplifier 8. The filter circuit 5 is for removing unnecessary signals from the signals from the amplifier circuit 4. The power supply means 6 applies a predetermined voltage for each function to the oscillation circuit 2, the modulation circuit 3 and the amplification circuit 4.

The amplifier circuit 4 is provided with a attenuation unit 7 that receives a signal from the modulation circuit 3 and attenuates the signal to a desired level. As shown in FIG. 2, the attenuator 7 is composed of two PIN diodes 9 and 10 connected in series. The PIN diodes 9 and 10 each have a coil 11 for removing or reducing parasitic capacitance. And 12, that is, the inductance elements are connected in parallel. The capacitors 13 and 14 are for cutting a direct current and passing a high frequency of 100%. L ₁ , L ₂ , L ₃ and L ₄ are inductance elements for cutting high frequency signals and passing 100% of direct current.

As shown in FIG. 2, the amplification section 8 includes an AMP 15 that amplifies signal power, and amplifies the signal from the attenuating section 7. Therefore, the amplifier circuit 4 can amplify the signal in a wider range of the total amplification range of the attenuation range of the water reducing section 7 and the amplification range of the amplification section 8.

The wireless transmitter 1 includes a PIN diode 16 and a ground line between the transmission line of the attenuator 7 and the ground in order to obtain the matching impedance (50Ω) between the attenuator 7 and the amplifier 8 in the amplifier circuit 4. 17 is interposed. That is, the PIN diodes 16 and 17 each stabilize the impedance between the transmission line and the ground by appropriately changing the direct current. In addition, the PIN diodes 16 and 17 have parasitic capacitances, but coils 18 and 19 for removing the parasitic capacitances and supplementing the stability of the impedance, that is, inductance elements are connected in parallel. The impedance of the AMP 15 of the amplifier 8 is 50Ω.

The wireless transmitter 1 is configured as described above. Here, when the wireless transmitter 1 is made to function, the power supply means 6 applies a predetermined voltage for each function to the oscillation circuit 2, the modulation circuit 3, the amplification circuit 4 and the filter circuit 5. At the same time, the oscillator circuit 2 oscillates a signal of a specific frequency by applying a voltage. The modulation circuit 3 receives the signal from the oscillation circuit 2 and modulates the amplitude of the signal to a desired level.

The amplifier circuit 4 amplifies the signal modulated by the modulation circuit 3 to a desired level so as to have a predetermined power. That is, the amplifier circuit 4 attenuates the signal input by the attenuator 7 to a desired magnitude of electric power, and the amplifier 8 amplifies the signal from the attenuator 7 to a desired magnitude of electric power. The filter 5 transmits, from the antenna 20, a signal obtained by removing unnecessary signals from the signals from the amplifier circuit 4.

Here, in the amplifier circuit 4, the PIN diodes 9 and 10 forming the attenuator 7 are said to have coils 11 and 12 connected in parallel and have the parasitic capacitance removed at all or almost all of them. Since it is removed as much as possible, the function of damping is performed almost according to the theoretical value. Therefore, both the PIN diodes 9 and 10 can have a larger attenuation width than in the case where there is a parasitic capacitance.

Here, the maximum attenuation amount when the PIN diodes 9 and 10 are used alone is −13 dB per PIN diode, whereas under the same conditions, the PIN diodes 9 and 10 are respectively reduced. The maximum attenuation when using the coils 11 and 12 connected in parallel was -23 dB per PIN diode.

FIG. 3 shows the variable voltage of the attenuator 7 when the PIN diodes 9 and 10 are used alone and when the coils 11 and 12 are connected in parallel to the PIN diodes 9 and 10, respectively. The relationship of the amount of attenuation with respect to is shown. FIG. 4 shows the variable voltage of the amplifier circuit 4 when the PIN diodes 9 and 10 are used alone and when the coils 11 and 12 are connected in parallel to the PIN diodes 9 and 10, respectively. The relationship of amplification gain is shown.

Further, the PIN diodes 16 and 17 are connected in parallel to the coils 18 and 19, respectively, and the parasitic capacitance is removed or almost completely removed. Sufficient matching is ensured between the impedances of 7 and the amplification section 8. Therefore, the operations of the modulation circuit 3 and the amplification unit 8 connected to the attenuator 7 are stable, and as a result, abnormal oscillation does not occur during actual operation. Further, since the gain of the amplifier circuit 4 is in accordance with the theory, it is possible to sufficiently control the entire device. In addition, since the frequency characteristic is as designed, it is possible to obtain an ideal frequency characteristic. In other words, the unstable behavior seen in the presence of parasitic capacitance was not observed.

In FIG. 5, under the same conditions, wireless transmission using the PIN diodes 16 and 17 alone and using the PIN diodes 16 and 17 with the coils 18 and 19 connected in parallel, respectively. The locus | trajectory of the impedance of the input or output of the attenuation part 7 with respect to the voltage change in the whole machine 1 is shown.

In the radio transmitter 1, in the amplifier circuit 4, the attenuator 7 is located on the front side and the amplifier 8 is located on the rear side, but the attenuator 7 is located on the rear side and the amplifier 8 is located on the front side. It may be configured to be placed.

In the radio transmitter 1, in the amplifier circuit 4, the PIN diodes 9 and 10 are connected in parallel with the coils 11 and 12, respectively, but the PIN diodes 9 and 10 are connected to microstrip lines, respectively. May be Similarly, the PIN diodes 16 and 17 of the amplifier circuit 4 may be replaced with the coils 11 and 12, respectively, and microstrip lines may be connected in parallel.

In the wireless transmitter 1, the attenuator 7 of the amplifier circuit 4 is configured to include two PIN diodes 9 and 10, but it may be configured to include only one PIN diode. Good.

[Effect of device]

 This invention interposes a PIN diode between the transmission line of the attenuating part that constitutes the amplifying circuit and the ground to obtain matching between the amplifying part and the attenuating part of the amplifying circuit, and the PIN diode has a parasitic capacitance. Since the coil or the microstrip line for eliminating the above is connected in parallel, the PIN diode ensures the matching as designed, and therefore the abnormal gain does not occur and the gain of the amplification is increased. Is a wireless transmitter that can be controlled as designed and as designed, and can take ideal values without the frequency characteristics deviating from the designed values.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a wireless transmitter according to an embodiment of the present invention.

FIG. 2 is a circuit diagram of an amplifier circuit of the embodiment shown in FIG.

FIG. 3 shows a case where a PIN diode that constitutes an attenuating portion of an amplifier circuit is used alone in the embodiment shown in FIG.
It is a characteristic curve figure which shows the relationship of the attenuation amount with respect to the variable voltage of an attenuator at the time of connecting a coil to IN diode in parallel.

FIG. 4 shows a case where a PIN diode that constitutes an attenuating portion of an amplifier circuit is used alone in the embodiment shown in FIG.
It is a characteristic curve figure which shows the relationship of the amplification gain with respect to the variable voltage of an amplifier circuit when connecting IN diode coil in parallel.

FIG. 5 is a diagram showing the entire apparatus in the embodiment shown in FIG. 1 when a PIN diode is used alone to obtain impedance matching between an attenuator and an amplifier and when a PIN diode is used in parallel with a coil; 5 is a characteristic curve diagram showing a locus of impedance of input or output of the attenuator with respect to voltage change in FIG.

[Explanation of symbols]

 1 Radio Transmitter 2 Oscillation Circuit 3 Modulation Circuit 4 Amplification Circuit 5 Filter Circuit 6 Power Supply Unit 7 Attenuator 8 Amplification Unit 9, 10, 16, 17 PIN Diode 11, 12, 18, 19 Coil

Claims (1)

[Scope of utility model registration request] 1. An oscillation circuit that oscillates a signal of a specific frequency by applying a voltage, a modulation circuit that modulates the amplitude of the signal from the oscillation circuit to a desired level, and the signal from the modulation circuit becomes a predetermined power. An amplifier circuit for amplifying, a filter circuit for removing unnecessary signals among signals from the amplifier circuit, and a power supply circuit for applying a predetermined voltage to the oscillation circuit, the modulation circuit and the amplifier circuit, The amplifier circuit includes an amplifier that amplifies the power of the input signal and an attenuator that attenuates the power of the input signal to a desired level, and an amplifier between the transmission line of the attenuator and the ground. A PIN diode for interposing the matching of the attenuator is interposed, and in addition, a coil or a microstrip line for removing a parasitic capacitance is connected in parallel to the PIN diode. Radio transmitter.