JP4081035B2 - Radar-mounted semiconductor power amplifier and radar transmitter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To control power for each pulse output signal, and to achieve high power efficiency in a semiconductor power amplifier used for a long/short compound pulse system radar device. <P>SOLUTION: An excitation signal comprising a long pulse excitation signal and a short pulse excitation signal outputted from a signal generator is inputted to an amplifier 12 via a voltage-controlled attenuator 16. The amplifier 12 outputs a long pulse output signal and a short pulse output signal, and radiates them from an antenna 36. The amplifier 12 operates as an AB-class amplifier, an A-class amplifier, or a B-class amplifier. A switch circuit 14 is provided at the power supply line of the amplifier 12, and an idling current is shut off when no excitation signals are inputted. The voltage-controlled attenuator 16 controls power for each pulse signal according to a control voltage from a pulse length determination circuit 18. The switch circuit 14 and the voltage-controlled attenuator 16 operate based on a control pulse signal outputted by a control pulse generation circuit 30. <P>COPYRIGHT: (C)2006,JPO&amp;NCIPI

Description

  The present invention relates to a semiconductor power amplifying device used in a transmission device such as an aerial surveillance radar device, a weather radar device, and a marine radar device.

  In recent years, semiconductor power amplifiers using FETs, bipolar transistors, etc. have been used in conventional surveillance, radar, weather radar, marine radars, etc. from the viewpoint of maintainability, reliability, and durability. It tends to be used in place of an electron tube power amplifier using the above.

  However, since the semiconductor power amplifier has not yet obtained the output power equivalent to that of the electron tube power amplifier, the radar apparatus compensates for the shortage of output power by using a long pulse output signal in which the transmission pulse length is extended. Further, since the radar apparatus cannot perform the transmission operation and the reception operation at the same time, there arises a problem that the undetectable area is expanded by extending the transmission pulse length. To solve this problem, a short pulse output signal with a short pulse length is radiated separately, and a long and short composite pulse method that combines a distant reception signal obtained with the long pulse output signal and a nearby reception signal obtained with the short pulse output signal. It is dealt with by adopting.

  A radar apparatus using a long / short composite pulse is disclosed on the Internet. A semiconductor power amplifier used in a radar apparatus is disclosed in Japanese Patent Laid-Open No. 9-321550.

JP-A-9-321550 Internet <URL: http://www9.ocn.ne.jp/~h-r-cab/solid_radar.htm>

  In the long / short composite pulse method, the output power required when the short pulse output signal is emitted is necessary for positioning a target at a distance below the minimum detection distance for the long pulse output signal, that is, a target in the vicinity. Determined by minimum output power. This output power is smaller than the output power required in the method of detecting the entire region only by a pulse train having a single pulse length, but is generally required when emitting a long pulse output signal. Will be bigger. Therefore, the output power is changed for each long and short pulse, and when the short pulse output signal is emitted, the output power is radiated with the output power necessary for positioning of the nearby target, and when the long pulse output signal is emitted, according to the extension of the pulse length. From the viewpoint of reducing power consumption, it is preferable to satisfy a desired detection region without excessive or insufficient power by radiating with reduced output power.

However, conventional radar semiconductor power amplifiers are mainly class C amplifiers, and fine power control for each pulse is difficult. This is because in the class C amplifier, the relationship between the input signal and the output signal is nonlinear, the input signal level reaches a level at which the output signal appears, and the output signal level reaches the maximum level with a rapid gain increase. . Therefore, the control of the output power for each pulse is not realized, and the same output power is radiated even when the long pulse output signal is radiated as when the short pulse output signal is radiated, and the average power consumption is large. Yes. Figure 7 is shows the output power of the conventional radar device using the class-C power amplifier, the power of P _U indicates to become excessive during long pulse output signal radiation. Here, the C-class amplifier conventionally has become the mainstream, it is because can achieve high power efficiency by the idling current is not required. Therefore, even when a class AB amplifier, a class A amplifier, or a class B amplifier is used, a power amplifier that is advantageous from the viewpoint of output power control can be obtained as long as power efficiency comparable to that of a class C amplifier can be realized. It can be realized.

  The present invention has been made paying attention to such a problem, and enables control without excess or deficiency in output power by using a class AB amplifier, a class A amplifier, or a class B amplifier. The semiconductor power amplifier which realizes the power efficiency which is not inferior to the class C amplifier by shutting off the power supply is provided.

The present invention relates to an amplifier circuit including a semiconductor amplifier , a switch circuit connected to a power supply terminal of the amplifier circuit, and an amplifier connected to an input terminal of the amplifier circuit to control the amplitude of the input signal. A semiconductor power amplifying apparatus for mounting on radar including an amplitude control circuit that outputs to a circuit, including a control pulse generation circuit that outputs a control pulse signal for controlling the switch circuit and the amplitude control circuit, and the amplitude control circuit Controls the amplitude of the signal output to the amplifier circuit based on the pulse time length at which the control pulse signal is on level, the switch circuit is turned on or off based on the level of the control pulse signal, The semiconductor amplifying element is in a state where an idling current flows when the switch circuit is on, and is idle when the switch circuit is off. A state in which current is interrupted, the amplifier circuit, and outputs a signal output from the amplitude control circuit and the switching circuit is amplified when on.

In the semiconductor power amplifying apparatus for mounting on radar according to the present invention, the control pulse generating circuit includes a short pulse that is on level with a first pulse time length and a second pulse that is longer than the first pulse time length. The control pulse signal including a long pulse having an on level with a pulse time length is output to the amplitude control circuit, and the amplitude control circuit has a level corresponding to the pulse time length of the control pulse signal. And an amplitude adjustment circuit that adjusts the amplitude of the signal output to the amplifier circuit based on the level of the amplitude control signal, and the amplitude adjustment circuit includes the control pulse generation circuit. The amplitude of the output signal when the short pulse is being output from the output signal is the amplitude of the output signal when the long pulse is being output from the control pulse generating circuit. As larger than, it is preferable to adjust the amplitude of the signal outputted to the amplifier circuit.

In the semiconductor power amplifying apparatus for mounting on radar according to the present invention , the control pulse generation circuit includes a short pulse period in which the short pulse is output from the control pulse generation circuit, and the long pulse from the control pulse generation circuit. The control pulse signal is output so that a long pulse period in which the control pulse signal is maintained at an off level is alternately repeated, and the pulse time length discriminating circuit outputs each short pulse period. A monostable multivibrator that changes the level of the output signal triggered by the level change of the control pulse signal at the end of the operation, and outputs the output signal as the amplitude control signal to the amplitude adjustment circuit, the monostable multivibrator Starts outputting a signal corresponding to the long pulse at the end of the short pulse period, and the short pulse period ends. After a long pulse period next to the short pulse period and before the start of the next short pulse period after the short pulse period, It is preferable to start outputting a signal corresponding to a pulse and maintain a state in which a signal corresponding to a short pulse is output during the next short pulse period.

In the radar-mounted semiconductor power amplification device according to the present invention, the amplitude adjustment circuit includes a variable attenuation circuit in which an attenuation amount changes according to a level of the amplitude control signal, and the variable attenuation circuit includes the amplitude It is preferable that the amount of attenuation when the level of the control signal is a level corresponding to a long pulse is larger than the amount of attenuation when the level of the amplitude control signal is a level corresponding to a short pulse .

Further, the radar-mounted semiconductor power amplifying device according to the present invention is used as a transmission power amplifying device, and a signal generator for outputting an excitation signal to the amplitude control circuit, and the excitation signal during a period when the control pulse signal is on level. A radar transmitter including a frequency changing circuit that changes the frequency of the signal can be configured.

Further, the radar-mounted semiconductor power amplification device according to the present invention is used as a transmission power amplification device, and the distance is longer than the long pulse minimum detection distance, which is the distance that the electromagnetic wave propagates in half the second pulse time length. Positioning of a target is performed when the long pulse is output from the control pulse generation circuit, and positioning of a target at a distance equal to or shorter than the long pulse minimum detection distance is performed, and the short pulse is detected from the control pulse generation circuit. It is possible to configure a radar transmission device that performs when output.

  According to the present invention, even when a class AB amplifier, a class A amplifier, or a class B amplifier is used in a radar transmitter, a performance equivalent to that of a class C amplifier and low power consumption can be realized. Can do. Also, in a long / short composite pulse system radar device, when radiating a short pulse output signal, it radiates with the output power necessary for positioning a nearby target, and when radiating a long pulse output signal, it is reduced according to the extension of the pulse length. It is possible to perform control such that radiation is performed with the output power thus generated, and it is possible to suppress excess or deficiency of the output power.

Embodiments of the present invention will be described with reference to the drawings. Figure 1 shows what the semi conductor power amplifying apparatus 1 was applied to the radar apparatus of long and short pulse complex method.

  The radar device described here emits short pulse output signals and long pulse output signals alternately, and synthesizes a distant received signal obtained by the long pulse output signal and a nearby received signal obtained by the short pulse output signal. By doing so, positioning of a target over a wide range is enabled.

  FIG. 2 shows the state of the short pulse output signal and the long pulse output signal. These output signals are output from the semiconductor power amplifier 1 and radiated from the antenna 36 via the circulator 38. When the pulse output signal radiated from the antenna 36 is applied to the target as an electromagnetic wave, a part of the power of the pulse output signal is reflected by the target to generate a reflected wave. The reflected wave is received by the antenna 36 and guided to the receiving device via the circulator 38. The received reflected wave includes information on the direction of the target, the distance to the target, and the reflection intensity, and the radar apparatus performs positioning of the target by processing this information.

In the radar device design, the output power P _L of the long pulse output signal and the pulse of the long pulse output signal are determined based on how far the target is positioned, what is the maximum output power of the device, etc. The length t _L is determined.

In order to extend the distance at which positioning is possible, the output power P _L may be increased or the pulse length t _L may be increased. This is because the receiving device of the radar device recognizes the presence of the target with the amount of received power. This means that the same distance measurement performance can be obtained if the amount of power obtained by the product of P _L and t _L is the same. Therefore, as long as the pulse length t _L is increased, the output power P _L can be reduced as long as the receiver performance of the radar apparatus permits.

However, since the radar apparatus cannot perform the transmission operation and the reception operation at the same time, the distance of the electromagnetic wave that can propagate in half the pulse length t _L , that is, the distance of the target existing at the distance below the minimum detection distance with respect to t _L. Positioning cannot be performed. Therefore, in determining P _L and t _L, the minimum detection distance with respect to t _L must be taken into consideration.

The target positioning of the objects present in the minimum detection distance following distance with respect to the pulse length t _L is short pulse output signal is used. The pulse length t _S of the short pulse output signal is determined according to the specifications for the distance resolution, and the minimum detection distance is determined along with it, and the output power P _S of the short pulse output signal is relative to t _L. It is determined based on the minimum output power required for positioning a target existing at a distance equal to or smaller than the minimum detection distance.

  Needless to say, not only the attenuation of the electromagnetic wave but also the directivity pattern of the antenna 36 needs to be considered when obtaining the required output power.

In general radar apparatus specifications, P _S determined in this way is larger than P _L , and the required output power differs between short pulse output signal emission and long pulse output signal emission. . In order to minimize the output power and reduce the power consumption, it is necessary to control the output power for each pulse.

  From this point of view, the transmission apparatus requires a circuit that generates a signal that controls the pulse length and generation timing of each of the short pulse output signal and the long pulse output signal, and a circuit that controls the power for each pulse. The circuit shown in FIG. 1 specifically realizes them, and the operation thereof will be described below together with signals handled by each circuit.

  The signals from (a) to (f) in FIG. 3 and the operation of each circuit that outputs them will be described. The excitation signal shown in FIG. 3A is a high-frequency signal that has been amplitude-modulated by a pulse, and includes a short pulse excitation signal and a long pulse excitation signal. This signal is amplified by the amplifier 12, is radiated as an electromagnetic wave to the target, and is used for positioning of the target. The high-frequency oscillation circuit 28 and the control pulse generation circuit 30 provided in the signal generation unit 2 of the radar apparatus. Generated by the timing adjustment circuit 32 and the long / short pulse modulator 34.

The control pulse generation circuit 30 generates a control pulse signal that determines the pulse length and generation timing. The state of the control pulse signal is shown in FIG. This signal is input to the long / short pulse modulator 34 after the timing adjustment circuit 32 adjusts the rise time and fall time. The control pulse signal output from the timing adjustment circuit 32 has a rise time that is later by Δ ₁ than the rise time of the original control pulse signal, and its fall is earlier by Δ ₂ than the original control pulse signal. Therefore, the pulse of the excitation signal is also adjusted for the rise time and fall time accordingly. The situation can be easily grasped by comparing FIG. 3 (a) and FIG. 3 (b). Thus, the timing adjustment of the pulse of the excitation signal is performed in order to accurately control the idling current in the semiconductor amplifying element 10 and to stabilize the output power from the radar apparatus at the time of rising and falling. It is.

Based on t _S and t _L described above, the pulse length of the control pulse signal is t _S '= Δ ₁ + t _S + Δ ₂ and the pulse length of the long pulse signal is t _L ' = Δ _1. + T _L + Δ ₂ is determined, and the generation interval of the long pulse signal and the short pulse signal may be determined based on the specifications of the radar apparatus. In the timing adjustment circuit 32, design parameters may be set so that the rising edge is advanced by Δ ₁ and the falling edge is delayed by Δ ₂ .

The excitation signal thus generated is input to the voltage controlled attenuator 16 and subjected to amplitude control. The amplitude V _S of the short pulse excitation signal subjected to amplitude control and the amplitude V _L of the long pulse excitation signal subjected to amplitude control are determined based on P _S and P _L described above, respectively. Specifically, V _S is determined such that the output power when the signal having the amplitude V _S is input to the amplifier 12 is P _S, and the output power when the signal having the amplitude V _L is input to the amplifier 12 is P _L. V _L may be determined so that FIG. 3D shows the state of the excitation signal subjected to amplitude control.

  The voltage-controlled attenuator 16 is a variable attenuator whose amount of attenuation changes according to a voltage applied from the outside, and can be configured by using a Pin diode. In order for the voltage controlled attenuator 16 to control the amplitude of the excitation signal, an attenuation control signal is required, and this signal is supplied from the pulse length discrimination circuit 18.

  The pulse length determination circuit 18 receives the control pulse signal output from the control pulse generation circuit 30, and generates an attenuation control signal that is a signal reflecting the pulse length in the voltage level. FIG. 3C shows the state of the attenuation control signal. The pulse length discriminating circuit 18 is constituted by a monostable multivibrator triggered by the fall of the short pulse signal of the control pulse signal, and outputs a high potential with the fall of the short pulse signal, while the long pulse signal rises. Continues to maintain a high potential output and switches to a low potential between the fall of the long pulse signal and the rise of the short pulse signal. Further, it is preferable to use the level conversion circuit 22 using a transistor or the like according to the control voltage range of the voltage controlled attenuator 16.

The excitation signal subjected to the amplitude control is input to the amplifier 12 . Here, before describing the operation when the excitation signal is amplified, the configuration and basic operation of the amplifier 12 will be described.

FIG. 1 shows a semiconductor amplifying element 10 constituting an amplifier 12 using an FET. As the FET, it is preferable to use a GaAsFET having excellent high frequency characteristics. A bias voltage is applied to the gate of the FET so that the amplifier 12 operates in class AB, class A or class B.

When the amplifier 12 operates in class A, a drain current that changes linearly with respect to a change in the input signal flows, so that the output power of the amplifier 12 is proportional to the input power. In addition, when the amplifier 12 operates in class AB or class B, the drain current is saturated in almost half of the input signal, so the output power is not proportional to the input power, but the output power is not proportional to the input power. There is a monotonically increasing relationship.

  A switch circuit 14 is provided on the current supply line connected to the drain of the FET. The switch circuit 14 can be composed of an FET and a bipolar transistor as shown in FIG. The switch circuit 14 is supplied with a control pulse signal and performs switching based on on and off. When the switch circuit 14 is in an ON state, an idling current flows through the drain of the FET, thereby enabling an amplification operation.

  Here, the switch circuit 14 is provided in the current supply line connected to the drain. However, the switch circuit 14 may be provided in a circuit (not shown) for supplying the gate bias voltage to switch the gate bias voltage. Good.

  When the switch circuit 14 is turned on and the excitation signal is input and amplified, a drain current flows suddenly, so that a power supply having a large current allowance is required. In the configuration of FIG. 1, a large capacity capacitor 24 is provided in the power supply line, and sufficient electric charge is stored when the switch circuit 14 is turned off, so that no load is applied to the power supply even if the current consumption changes suddenly. It is said.

  Next, an operation when an excitation signal composed of a short pulse excitation signal and a long pulse excitation signal is amplified will be described.

The switch circuit 14 is switched on by Δ ₁ before the input of the short pulse excitation signal is started by the rising edge of the control pulse signal, and causes an idling current to flow through the amplifier 12 . The reason why the idling current is allowed to flow before the short pulse excitation signal is input is to reliably obtain the output power even at the rising edge. This operation is made possible by the timing adjustment circuit 32 adjusting the timing of the control pulse signal input to the long / short pulse modulator 34 as described above.

Amplifier 12 that are already supplied with idling current, output power receives the short pulse excitation signal and outputs a short pulse output signal which is a P _S. While the short pulse output signal is being output, the voltage controlled attenuator 16 exhibits a certain amount of attenuation so that the amplitude of the short pulse excitation signal becomes V _S.

The amplifier 12 continues to output P _S power during the pulse length t _S of the short pulse output signal, and stops outputting as the short pulse excitation signal falls. The control pulse signal falls after Δ ₂ from the fall of the short pulse excitation signal, and the idling current of the amplifier 12 is cut off.

The control pulse signal continues to maintain the low voltage level until Δ _{1 when} the input of the long pulse excitation signal starts. As a result, the switch circuit 14 remains off and the idling current of the amplifier 12 is cut off, so that no power is consumed in the amplifier 12 .

Next, the switch circuit 14 is switched on by Δ ₁ before the input of the long pulse excitation signal is started by the rising of the control pulse signal, and causes an idling current to flow through the amplifier 12 . Thereafter, similarly to the case where the short pulse excitation signal is input, a long pulse output signal whose output power is P _L is output, and the long pulse output signal and the short pulse output signal are alternately output.

FIG. 3 (e) shows the state of the drain current, and FIG. 3 (f) shows the state of the output power. Since there is a time difference of Δ ₁ and Δ ₂ between the excitation signal and the control pulse signal, there is a period when only the idling current flows in the drain current, and the idling current always flows when the excitation signal rises. You can see that it is in a state.

  In FIG. 1, the control pulse signal is supplied to the timing adjustment circuit 32, the pulse length determination circuit 18 and the switch circuit 14. However, at the same signal input end of each circuit, the level adjustment and waveform shaping are performed by the comparator 20 or the like. It is preferable to carry out. The comparator 20 in FIG. 1 is a specific circuit notation.

  A matching circuit for avoiding an increase in in-band amplitude ripple due to impedance mismatch, a decrease in signal level, and the like is provided at a connection end of a circuit that handles high-frequency signals such as the high-frequency oscillation circuit 28, the long / short pulse modulator 34, and the amplifier 12. 26 is preferably provided.

  FIG. 4 shows a configuration in which the output power is increased by connecting the semiconductor power amplification devices 1 according to the present invention in parallel. Outputs of the respective semiconductor power amplifying devices 1 are combined by the power combiner 40, and transmission power is output as one system. This is a particularly effective configuration when using a semiconductor having a smaller output power than that of an electron tube.

  The above has described an example of the long and short composite pulse system in which the short pulse output signal and the long pulse signal are radiated alternately at intervals. Another form of the system is as shown in FIG. This is a system in which a long pulse output signal and a short pulse output signal are continuously radiated by changing the frequency of an electromagnetic wave radiated within one pulse, and can be said to be a long / short composite pulse system using a single pulse. FIG. 6 shows a configuration when the semiconductor power amplification device 1 according to the present invention is applied to this system. The control pulse signal is input to the frequency change circuit 42, and the oscillation frequency of the high frequency oscillation circuit 28 is changed within the pulse time. The frequency is preferably changed by defining a certain frequency range and performing sweeping within that range.

It is a figure which shows the signal generation part in a semiconductor power amplifier and a radar apparatus. It is a figure which shows the mode of a short pulse output signal and a long pulse output signal. It is a figure which shows the timing of the signal handled with a semiconductor power amplifier. It is a figure which shows the structure which connected the semiconductor power amplifier device in parallel. It is a figure which shows the output signal in the long-short composite system by a single pulse. It is a figure which shows the structure at the time of applying a semiconductor power amplifier to the long-short composite system by a single pulse. It is the figure which showed the output electric power of the conventional radar apparatus using a class-C amplifier.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Semiconductor power amplifier 2, 2 Signal generation part, 10 Semiconductor amplifier, 12 Amplifier, 14 Switch circuit, 16 Voltage control attenuator, 18 Pulse length discrimination circuit, 20 Comparator, 22 Level conversion circuit, 24 Capacitor, 26 Matching circuit, 28 high frequency oscillation circuit, 30 control pulse generation circuit, 32 timing adjustment circuit, 34 long / short pulse modulator, 36 antenna, 38 circulator, 40 power combiner, 42 frequency change circuit.

Claims (6)

An amplifying circuit including a semiconductor amplifying element;
A switch circuit connected to a power supply terminal of the amplifier circuit;
Connected to said input terminal of the amplifier circuit, a semiconductor power amplifier device for a radar mount comprising an amplitude control circuit for controlling the amplitude of the input signal and outputs it to the amplifier circuit,
A control pulse generating circuit for outputting a control pulse signal for controlling the switch circuit and the amplitude control circuit;
The amplitude control circuit controls the amplitude of a signal output to the amplifier circuit based on a pulse time length at which the control pulse signal is on level,
The switching circuit is turned on or off based on the level of the control pulse signal,
The semiconductor amplifying element is in a state where an idling current flows when the switch circuit is on, and is in a state where the idling current is interrupted when the switch circuit is off,
The amplifier circuit includes a semiconductor power amplifier device for a radar mounted thereon and outputs the signal output from the amplitude control circuit and the switching circuit is amplified when on. A semiconductor power amplifier for mounting radar according to claim 1 ,
The control pulse generation circuit includes the short pulse that is turned on at a first pulse time length and the long pulse that is turned on at a second pulse time length longer than the first pulse time length. Output a pulse signal to the amplitude control circuit,
The amplitude control circuit includes a pulse time length determination circuit that outputs an amplitude control signal having a level corresponding to a pulse time length of the control pulse signal ;
The amplitude of the signal outputted to the amplifier circuit includes an amplitude adjustment circuit for adjustment based on the level of the amplitude control signal,
The amplitude adjustment circuit is configured such that the amplitude of the output signal when the short pulse is output from the control pulse generation circuit is greater than the amplitude of the output signal when the long pulse is output from the control pulse generation circuit. A radar-mounted semiconductor power amplification device , wherein the amplitude of a signal output to the amplification circuit is adjusted so as to increase. A radar-mounted semiconductor power amplification device according to claim 2 ,
In the control pulse generation circuit , the control pulse signal is turned off between a short pulse period in which the short pulse is output from the control pulse generation circuit and a long pulse period in which the long pulse is output from the control pulse generation circuit. Outputting the control pulse signal to be alternately repeated with a period maintained at a level ,
The pulse time length determination circuit changes the level of the output signal triggered by the level change of the control pulse signal at the end of each short pulse period, and outputs the output signal to the amplitude adjustment circuit as the amplitude control signal a monostable multivibrator seen contains,
The monostable multivibrator starts output of a signal corresponding to a long pulse at the end of a short pulse period, and after the short pulse period ends, the short pulse period exceeds the long pulse period next to the short pulse period. Until the start of the next short pulse period of the pulse period, after maintaining the state of outputting the signal of the long pulse corresponding level, the output of the signal of the short pulse corresponding level is started and the output of the next short pulse period is started. A semiconductor power amplifying apparatus for mounting on radar, which maintains a state of outputting a signal of a level corresponding to a short pulse . A radar-mounted semiconductor power amplifying device according to claim 3 ,
The amplitude adjustment circuit includes a variable attenuation circuit in which an attenuation amount changes according to a level of the amplitude control signal ,
The variable attenuation circuit is:
A radar-mounted semiconductor power characterized in that an attenuation amount when the level of the amplitude control signal is a level corresponding to a long pulse is larger than an attenuation amount when the level of the amplitude control signal is a level corresponding to a short pulse. Amplification equipment. A radar transmitter using the radar-mounted semiconductor power amplifier according to any one of claims 1 to 4 as a transmission power amplifier,
  A signal generator for outputting an excitation signal to the amplitude control circuit;
  A frequency changing circuit for changing the frequency of the excitation signal during a period in which the control pulse signal is on level;
  A radar transmitter comprising: A radar transmission device using the radar-mounted semiconductor power amplification device according to any one of claims 2 to 4 as a transmission power amplification device,
The positioning of the target object at a distance before Symbol electromagnetic wave at a second pulse duration of half the time exceeds the length pulse minimum detection distance which is a distance propagation, when the long pulse is outputted from the control pulse generating circuit to perform the positioning of the target object at a distance of less than the length pulse minimum detectable range, the radar transmitting apparatus characterized that you do when the short pulse is output from the control pulse generating circuit.

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