WO2021084633A1 - Transmitter and transmitter/receiver - Google Patents

Abstract

A transmitter (1) is configured so as to comprise: a chirp rate setting unit (51) that sets a chirp rate α of a signal to be transmitted on the basis of a regulatory value EIRP of a transmitted power density SP in the signal to be transmitted; a signal generating unit (52) that generates the signal to be transmitted, varying in frequency according to the chirp rate α set by the chirp rate setting unit (51); and a transmitting unit (53) that transmits the signal to be transmitted, the signal being generated by the signal generating unit (52).

Description

Transmitter and transmitter / receiver

The present invention relates to a transmission device that transmits a transmission signal and a transmission / reception device that transmits a transmission signal and generates a reception signal.

When the transmission power per unit frequency of the transmission signal transmitted from the transmission device (hereinafter referred to as "transmission power density") becomes large, the transmission device causes radio wave interference to the communication device existing in the vicinity of the transmission device. May give. In order to prevent radio wave interference, some countries have set a regulation value for the transmission power density of the transmission signal transmitted from the transmission device.
For example, the Radio Law of Japan stipulates the upper limit of electric field strength as equivalent to the regulation value of transmission power density (hereinafter, simply referred to as "regulation value"). Specifically, the Radio Law of Japan stipulates the upper limit of the electric field strength at a point 3 m from the weak radio station, for example, when a weak radio station is installed as a transmitting device, according to the frequency of the transmitted signal. ing.

By the way, some transmitters spread the carrier frequency by a random code sequence for the purpose of lowering the transmission power density (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 1-66585

When the transmission signal transmitted from the transmission device is a signal whose carrier frequency is spread spectrum by a random code sequence, the transmission power density of the transmission signal may be larger than the regulation value.
There is a problem that a transmission device in which the transmission power density of a transmission signal becomes larger than the regulation value cannot be used in an environment where the transmission power density is regulated.

The present invention has been made to solve the above problems, and an object of the present invention is to obtain a transmission device and a transmission / reception device that can be used even in an environment where the transmission power density is regulated.

In the transmission device according to the present invention, the frequency changes depending on the chirp rate setting unit that sets the chirp rate of the transmission signal and the chirp rate set by the chirp rate setting unit based on the regulation value of the transmission power density in the transmission signal. It is provided with a signal generation unit that generates a transmission signal and a transmission unit that transmits a transmission signal generated by the signal generation unit.

According to the present invention, the transmission device is configured to include a chirp rate setting unit that sets the chirp rate of the transmission signal based on the regulation value of the transmission power density in the transmission signal. Therefore, the transmitter according to the present invention can be used even in an environment where the transmission power density is regulated.

It is a block diagram which shows the hardware of the transmission / reception device which concerns on Embodiment 1. FIG. It is a block diagram which shows the function of the transmission / reception device which concerns on Embodiment 1. FIG. It is a flowchart which shows the process of the transmission device 1 which concerns on Embodiment 1. FIG. It is explanatory drawing which shows the chirp signal which is a transmission signal. It is explanatory drawing which shows the transmission power density of the transmission signal when the transmission signal is a chirp signal. It is explanatory drawing which shows the transmission power density of a chirp signal when the chirp rate α of a chirp signal is larger than the chirp rate α of the chirp signal shown in FIG. 5 and does not satisfy the relation of the equation (2). It is a block diagram which shows the function of the transmission / reception device which concerns on Embodiment 2. FIG. It is explanatory drawing which shows an example of the transmission power density SP which is larger than the regulation value EIRP. The transmission gain G _Tx, is an explanatory diagram showing a state of lowering the high transmission power density SP to the restriction value EIRP. It is explanatory drawing which shows an example of the transmission power density SP which is smaller than a regulation value EIRP. The transmission gain G _Tx, is an explanatory diagram showing a state of raising the low transmission power density SP to the restriction value EIRP.

Hereinafter, in order to explain the present invention in more detail, a mode for carrying out the present invention will be described with reference to the accompanying drawings.

Embodiment 1.
FIG. 1 is a configuration diagram showing the hardware of the transmission / reception device according to the first embodiment. The transmission / reception device shown in FIG. 1 includes a transmission device 1 and a reception device 2.
FIG. 2 is a configuration diagram showing the functions of the transmission / reception device according to the first embodiment.

In FIG. 1, an EEPROM (Electrically Erasable Program Read-Only Memory) 11 stores a program or the like showing a processing procedure of an FPGA (Field Programmable Gate Array) 12, which will be described later.
The FPGA 12 reads the program stored in the EEPROM 11 and operates according to the processing procedure indicated by the program in synchronization with the clock signals of _{the frequencies f CLK and FGPA output from the clock 13 described later.}
The FPGA 12 sets the chirp rate α of the transmission signal by operating according to the processing procedure indicated by the program, and outputs the chirp rate α to the DDS (Direct Digital Synthesizer) 14, which will be described later.
_{Further, the FPGA 12 sets the transmission gain G Tx} of the transmission signal by operating according to the processing procedure indicated by the program, and sets the transmission gain G _Tx to the transmission variable attenuator (hereinafter, referred to as “ATT”) 17 described later. Output.
However, in transmission and reception apparatus shown in FIG. 1, for convenience of explanation, FPGA 12 is, the gain is assumed to set the transmission gain _{G Tx} "1".

The EEPROM 11 and the FPGA 12 execute the function of the chirp rate setting unit 51 shown in FIG.
The chirp rate setting unit 51 sets the chirp rate α of the transmission signal based on the regulation value EIRP of the transmission power density in the transmission signal.
The chirp rate setting unit 51 outputs the chirp rate α to the signal generation unit 52, which will be described later.

The clock 13 oscillates a clock signal having a frequency of f _CLK.
The clock 13 is the clock signal of frequency _{f CLK,} as the system clock of DDS14, frequency _{f CLK,} and generates a _DDS clock signal, and outputs the frequency _{f CLK,} the _DDS clock signal DDS14.
The clock 13 is the clock signal of frequency _{f CLK,} as the operation clock of the FPGA 12, the frequency _{f CLK,} and generates a clock signal of _FGPA, and outputs the frequency _{f CLK,} a clock signal of _FGPA the FPGA 12.
The clock 13 is the clock signal of frequency _{f CLK,} as a sampling clock described later ADC 26, the frequency _{f CLK,} and generates a clock signal of the _ADC, and outputs the frequency _{f CLK,} the clock signal of the _ADC to the ADC 26.
The clock 13 is the clock signal of frequency _{f CLK,} as the operation clock of the processor 27 to be described later, the frequency _{f CLK,} and generates a clock signal of _Pro, and outputs the frequency _{f CLK,} a clock signal of _Pro processor 27.

The DDS 14 is a device capable of very high-speed frequency sweeping from low frequency to high frequency, and operates in synchronization with the clock signals of _{frequencies f CLK and DDS output from the clock 13 to generate a chirp signal.} Generate.
The DDS 14 outputs the generated chirp signal to a bandpass filter (hereinafter, referred to as “BPF”) 15 described later.
The clock 13 and the DDS 14 execute the function of the signal generation unit 52 shown in FIG.

The signal generation unit 52 generates a transmission signal whose frequency changes according to the chirp rate α set by the chirp rate setting unit 51, and outputs the transmission signal to each of the transmission unit 53 and the reception unit 54.

Among the frequency components included in the transmission signal output from the DDS 14, the BPF 15 includes a frequency component whose frequency is lower than the lower limit frequency of the chirp signal which is the transmission signal (hereinafter, referred to as “start frequency”) and the chirp. It blocks passage with frequency components whose frequency is higher than the upper limit frequency of the signal (hereinafter referred to as "end frequency").
Therefore, the BPF 15 passes only the frequency components included in the frequency band between the start frequency and the end frequency among the frequency components included in the transmission signal output from the DDS 14.

The distributor (hereinafter referred to as “div”) 16 distributes the transmission signal that has passed through the BPF 15 into two.
The div 16 outputs one transmitted signal after distribution to the ATT 17, and outputs the other transmitted signal after distribution to a mixer (hereinafter, referred to as “MIX”) 24 described later.
ATT17 is the transmission gain _{G Tx} outputted from the FPGA 12, and multiplies the transmission signal output from the Div16, and outputs to the transmitting antenna 18 to be described later transmission signal after transmission gain multiplication.
However, in transmission and reception apparatus shown in FIG. 1, for convenience of explanation, the FPGA 12, the gain is set the transmission gain _{G Tx} of "1", ATT17 also amplifies the transmission signal and does not even attenuation of the transmitted signal .. Therefore, the transmission / reception device shown in FIG. 1 corresponds to the fact that the ATT 17 is not provided.

BPF15, div16 and ATT17 execute the function of the transmission unit 53 shown in FIG.
The transmission unit 53 outputs the transmission signal generated by the signal generation unit 52 to the transmission antenna 18, so that the transmission signal is transmitted from the transmission antenna 18.

The transmitting antenna 18 transmits the transmission signal output from the ATT 17 toward the receiving device 2.
The receiving antenna 21 receives the transmission signal or the like transmitted from the transmission device 1 and outputs the received signal to the BPF 22 described later.

Of the frequency components contained in the signal output from the receiving antenna 21, the BPF 22 has a frequency component lower than the start frequency of the chirp signal and a frequency component higher than the end frequency of the chirp signal, similar to the BPF 15. Blocks passage with frequency components.
Therefore, the BPF 22 passes only the frequency components included in the frequency band between the start frequency and the end frequency among the frequency components included in the signal output from the receiving antenna 21.
The low noise amplifier (hereinafter referred to as “LNA”) 23 amplifies the signal that has passed through the BPF 22, and outputs the amplified signal to the MIX 24.

The MIX 24 generates a beat signal by mixing the amplified signal output from the LNA 23 and the transmission signal output from the div 16, and the beat signal is referred to as a low-pass filter (hereinafter, referred to as “LPF”) described later. ) Output to 25.
The LPF 25 passes the beat signal output from the MIX 24 and blocks the passage of noise such as harmonics output from the MIX 24.

_{The ADC 26 samples the beat signal that has passed through the LPF 25 according to the clock signals of frequencies f CLK and ADC} output from the clock 13, and converts the sampled beat signal from an analog signal to a digital signal.
The ADC 26 outputs a digital signal to the processor 27 as a reception signal of the receiving device 2.

The BPF22, LNA23, MIX24, LPF25 and ADC26 perform the function of the receiver 54 shown in FIG.
The receiving unit 54 generates a received signal from the signal received by the receiving antenna 21 and the transmission signal generated by the signal generating unit 52.

Each time the processor 27 receives a received signal from the ADC 26, the processor 27 stores the received signal in the memory 28 described later.
Further, the processor 27 performs a process of demodulating the data included in the received signal output from the ADC 26 in synchronization with the clock signals of _{the frequencies f CLK and Pro output from the clock 13, or sets a target from the received signal.} Perform detection processing, etc. The processor 27 outputs the demodulation processing result, the target detection processing result, and the like to each of the data storage 29 and the display unit 30 described later.

The processor 27 executes the function of the signal processing unit 55 shown in FIG.
The signal processing unit 55 performs a process of demodulating the data included in the received signal, a process of detecting a target from the received signal, and the like.

The memory 28 is a recording medium for recording a received signal.
The data storage 29 is realized by, for example, a magnetic storage medium or a semiconductor element memory.
The data storage 29 is a recording medium for recording the demodulation processing result or the target detection processing result output from the processor 27.
The display unit 30 displays the demodulation processing result or the target detection processing result output from the processor 27.

Next, the operation of the transmission / reception device shown in FIGS. 1 and 2 will be described.
FIG. 3 is a flowchart showing the processing of the transmission device 1 according to the first embodiment.
First, the chirp rate setting unit 51 sets the chirp rate α of the transmission signal based on the regulation value EIRP of the transmission power density in the transmission signal (step ST1 in FIG. 3).
Hereinafter, the chirp rate α setting process by the chirp rate setting unit 51 will be specifically described.

The chirp rate α is represented by the ratio of the frequency step width Δf to the time step width Δt of the chirp signal, as shown in the following equation (1). The time step width Δt is the length of the time zone in which the frequency is constant in the chirp signal, and corresponds to the time width of the clock signals of the _{frequencies f CLK and FPGA generated by the clock 13.} The frequency step width Δf is the frequency change width per time in the chirp signal.

FIG. 4 is an explanatory diagram showing a chirp signal which is a transmission signal.
For example, when the time step width Δt of the chirp signal is constant, the chirp ratio α increases as the frequency step width Δf increases, and the chirp ratio α decreases as the frequency step width Δf decreases.

FIG. 5 is an explanatory diagram showing the transmission power density of the transmission signal when the transmission signal is a chirp signal. In FIG. 5, SP ₁ is the transmission power density of the transmission signal when the transmission signal is a chirp signal. The transmission power density SP ₁ has the same value as the transmission power density of a transmission signal having a constant frequency when the chirp ratio α and f _{RBW satisfy the relationship of the following equation (2).}

In the formula (2), f _RBW is the filter width of the IF (Intermediate Frequency) filter mounted by the measuring device for measuring the electric field strength at a point of, for example, 3 m from the transmitting antenna 18 of the transmitting device 1.
FIG. 6 is an explanatory diagram showing the transmission power density of the chirp signal when the chirp rate α of the chirp signal is larger than the chirp rate α of the chirp signal shown in FIG. 5 and does not satisfy the relationship of the equation (2). is there. In FIG. 6, SP ₂ is the transmission power density of the chirp signal when the chirp ratio α of the chirp signal is larger than the chirp ratio α of the chirp signal shown in FIG. 5 and does not satisfy the relationship of the equation (2). is there.

When each of the chirp signal shown in FIG. 5 and the chirp signal shown in FIG. 6 is generated from the transmission signal shown in FIG. 4, the frequency of the transmission signal shown in FIG. 4 is spread spectrum of each chirp signal. It is a thing. Since the chirp signal shown in FIG. 6 has a larger spectral diffusion rate than the chirp signal shown _{in FIG. 5, the transmission power density SP 2} of the chirp signal shown in FIG. 6 is the transmission power density SP of the chirp signal shown in FIG. _Less than 1.

_{The relationship between the attenuation rate L rop} of the transmission power density SP due to spectral diffusion and the chirp rate α of the chirp signal is expressed by the following equation (3). The attenuation factor L _rop is the attenuation rate of the transmission power density SP of the chirp signal from the transmission power density of the transmission signal from which the chirp signal is generated.

However, when the chirp ratio α is equal to or less than the square value of the _{filter width f RBW (see equation (2)), L rop} = 1.
The measuring device receives the transmission signal transmitted from the transmission antenna 18 of the transmission device 1, and measures the electric field strength in a desired frequency band from the received signal that has passed through the IF filter.
The IF filter is realized by, for example, BPF. The filter width f _RBW of the IF filter has, for example, a width corresponding to the pass band of the BPF 15 shown in FIG.
The filter width f _RBW of the IF filter is an existing value and is stored in the internal memory of the chirp rate setting unit 51. However, the filter width f _RBW may be given to the chirp rate setting unit 51 from the outside of the transmission / reception device shown in FIG.
_{As shown in Eq. (3), the attenuation rate L rop} of the transmission power density SP due to spectral diffusion increases as the chirp rate α of the chirp signal increases, and the transmission power density SP becomes the attenuation rate L of the transmission power density SP. _The larger the probe, the smaller it becomes. Therefore, the transmission power density SP ₂ of the chirp signal shown in FIG. 6 is smaller than _{the transmission power density SP 1 of the} chirp signal shown in FIG. 5, as described above.

The condition that the transmission power density SP of the chirp signal, which is the transmission signal, becomes equal to or less than the regulation value EIRP is shown in the following equation (4).

In the formula (4), P ₀ is the transmission power of the transmission signal from which the chirp signal is generated, that is, the transmission power of the transmission signal having a constant frequency. Each of the regulated value EIRP and the transmission power P ₀ is an existing value and is stored in the internal memory of the chirp rate setting unit 51. However, each of the regulated value EIRP and the transmission power P ₀ may be given to the chirp rate setting unit 51 from the outside of the transmission / reception device shown in FIG.

The chirp rate setting unit 51 calculates _{the attenuation rate L rop of the transmission power density SP by substituting the transmission power P 0} of the transmission signal having a constant frequency and the regulation value EIRP into the following equation (5).

Next, the chirp rate setting unit 51 calculates the chirp rate α by substituting the _{attenuation factor L rop} and the filter width f _{RBW into the equation (3).}
The chirp rate setting unit 51 outputs the calculated chirp rate α to the signal generation unit 52.

When the signal generation unit 52 receives the chirp rate α from the chirp rate setting unit 51, the signal generation unit 52 generates a chirp signal having a chirp rate α, that is, a transmission signal whose frequency changes depending on the chirp rate α (step ST2 in FIG. 3). ..
Since the process of generating a transmission signal whose frequency changes depending on the chirp rate α is a known technique, detailed description thereof will be omitted.
The start frequency of the chirp signal and the end frequency of the chirp signal are already values and are stored in the internal memory of the chirp rate setting unit 51. However, each of the start frequency and the end frequency may be given to the chirp rate setting unit 51 from the outside of the transmission / reception device shown in FIG.
The signal generation unit 52 outputs the generated transmission signal to each of the transmission unit 53 and the reception unit 54.

When the transmission unit 53 receives the transmission signal from the signal generation unit 52, the transmission unit 53 outputs the transmission signal to the transmission antenna 18 (step ST3 in FIG. 3).
The transmitting antenna 18 transmits the transmission signal output from the transmitting unit 53 toward the receiving device 2 (step ST4 in FIG. 3).

The receiving antenna 21 receives a transmission signal or the like transmitted from the transmitting device 1, and outputs the received signal to the receiving unit 54.
The receiving unit 54 generates a received signal from the signal received by the receiving antenna 21 and the transmission signal generated by the signal generating unit 52, and outputs the received signal to the signal processing unit 55.

When the signal processing unit 55 receives the received signal from the receiving unit 54, the signal processing unit 55 performs a process of demodulating the data contained in the received signal, a process of detecting a target from the received signal, and the like.
The signal processing unit 55 outputs the demodulation processing result, the target detection processing result, and the like to the display unit 30.
The display unit 30 displays the demodulation processing result or the target detection processing result output from the signal processing unit 55.

In the first embodiment described above, the chirp rate setting unit 51 that sets the chirp rate α of the transmission signal and the chirp rate set by the chirp rate setting unit 51 based on the regulation value EIRP of the transmission power density SP in the transmission signal. The transmission device 1 is configured to include a signal generation unit 52 that generates a transmission signal whose frequency changes depending on α, and a transmission unit 53 that transmits a transmission signal generated by the signal generation unit 52. Therefore, the transmission device 1 can be used even in an environment where the transmission power density SP is regulated.

In the receiving device 2 shown in FIG. 1, the signal processing unit 55 performs a process of demodulating the data contained in the received signal output from the receiving unit 54, a process of detecting a target from the received signal, and the like. There is.
For example, when the signal processing unit 55 executes a process of detecting a target, each time the receiving unit 54 generates a received signal, the signal processing unit 55 integrates the received signals, so that a plurality of signals repeatedly generated by the receiving unit 54 The received signals of may be added.
When the signal processing unit 55 adds a plurality of received signals repeatedly generated by the receiving unit 54, the power of the received signal is increased, so that the target detection accuracy is improved.
The signal processing unit 55 also adds a plurality of received signals repeatedly generated by the receiving unit 54 when performing a process of demodulating the data included in the received signal output from the receiving unit 54. It may be.

In the receiving device 2 shown in FIG. 1, the signal processing unit 55 may calculate the correlation between the transmission signal generated by the signal generation unit 52 and the reception signal generated by the reception unit 54.
Since the process itself for calculating the correlation between the transmitted signal and the received signal is a known technique, detailed description thereof will be omitted.
For example, if the correlation value, which is the result of the correlation calculation, is equal to or greater than the threshold value, the signal processing unit 55 determines that the received signal is a signal that has received the transmission signal transmitted from the transmission device 1.
Further, if the correlation value is smaller than the threshold value, the signal processing unit 55 determines that the received signal is not a signal that has received the transmission signal transmitted from the transmission device 1.
If the signal processing unit 55 determines that the transmission signal transmitted from the transmission device 1 is a received signal, the signal processing unit 55 demodulates the data contained in the reception signal output from the reception unit 54, or the reception signal. Perform processing to detect the target from.
If the signal processing unit 55 determines that the transmission signal transmitted from the transmission device 1 is not a received signal, the signal processing unit 55 discards the received signal output from the receiving unit 54, demodulates the data, and uses the received signal. Do not perform processing to detect the target.

In the transmission device 1 shown in FIG. 1, the chirp rate setting unit 51 calculates a chirp rate α that matches the multiplication value _{of the attenuation rate L rop} of the transmission power density SP and the square value of the filter width f _RBW. There is.
However, this is only an example, and the chirp rate setting unit 51 may calculate the chirp rate α so as to be larger than the multiplication value. If the chirp rate α is larger than the multiplication value, the transmission device 1 can be used even in an environment where the transmission power density SP is regulated. However, if the chirp rate α becomes too large than the multiplication value, the transmission power density SP of the transmission signal becomes small, and it becomes difficult for the receiving device 2 to receive the transmission signal transmitted from the transmitting device 1. is there. Therefore, even if the chirp rate α is larger than the multiplication value, it is desirable that the chirp rate setting unit 51 calculate the chirp rate α that is close to the multiplication value.

In the transmission device 1 shown in FIG. 1, the EEPROM 11 executes the function of the chirp rate setting unit 51 shown in FIG. However, if the function of the chirp rate setting unit 51 shown in FIG. 2 can be executed, the transmission device 1 may be provided with hardware other than the EEPROM 11. Therefore, the transmission device 1 is provided with, for example, a CPU (Central Processing Unit), a central processing unit, a processing device, an arithmetic unit, a microprocessor, a microcomputer, a processor, or a DSP (Digital Signal Processor) instead of the EEPROM 11. You may.

In the transmission device 1 shown in FIG. 1, the DDS 14 executes the function of the signal generation unit 52 shown in FIG. However, if the function of the signal generation unit 52 shown in FIG. 2 can be executed, the transmission device 1 may be provided with hardware other than the DDS 14. Therefore, the transmission device 1 may include, for example, a PLL (Phase Locked Loop) instead of the DDS 14.

In the receiving device 2 shown in FIG. 1, the processor 27 executes the function of the signal processing unit 55 shown in FIG. However, the receiving device 2 may include hardware other than the processor 27 as long as the function of the signal processing unit 55 shown in FIG. 2 can be executed. Therefore, the receiving device 2 may include, for example, a CPU, a central processing unit, a processing device, an arithmetic unit, a microprocessor, a microcomputer, a processor, or a DSP instead of the processor 27.

Embodiment 2.
In the second embodiment, the transmission device 1 including the transmission gain setting unit 62 for setting the transmission gain _{GTx of the transmission signal will be described.}

FIG. 7 is a configuration diagram showing the functions of the transmission / reception device according to the second embodiment. In FIG. 7, the same reference numerals as those in FIG. 2 indicate the same or corresponding parts, and thus the description thereof will be omitted.
In the second embodiment, the EEPROM 11 and the FPGA 12 shown in FIG. 1 execute the respective functions of the chirp rate setting unit 61 and the transmission gain setting unit 62 shown in FIG. 7.
The chirp rate setting unit 61 sets the chirp rate α'of the transmission signal.
The chirp rate setting unit 61 outputs the chirp rate α'to each of the transmission gain setting unit 62 and the signal generation unit 52.
Transmission gain setting unit 62, based on the set chirp rate alpha 'as the regulated value EIRP and chirp rate setting unit 61 of the transmission power density SP in a transmission signal, to set the transmission gain G _Tx of the transmitted signal.
The transmission gain setting unit 62 _{outputs the transmission gain GTx} to the transmission unit 63, which will be described later.

In the second embodiment, the BPF15, the div16 and the ATT17 shown in FIG. 1 execute the function of the transmission unit 63 shown in FIG.
Transmission unit 63, by multiplying the transmission signal generated by the signal generating unit 52 to transmit gain G _Tx that is set, and outputs the transmission signal after transmission gain multiplication to the transmission antenna 18 by the transmission gain setting unit 62, A transmission signal is transmitted from the transmission antenna 18.

Next, the operation of the transmission / reception device shown in FIG. 7 will be described.
The chirp rate setting unit 61 sets the chirp rate α'of the transmission signal.
The chirp rate α'set by the chirp rate setting unit 61 may be larger or smaller than the chirp rate α set by the chirp rate setting unit 51 shown in FIG. Further, the chirp rate α'may be the same as the chirp rate α.
The chirp rate setting unit 61 outputs the chirp rate α'to each of the signal generation unit 52 and the transmission gain setting unit 62.

When the signal generation unit 52 receives the chirp rate α'from the chirp rate setting unit 61, the signal generation unit 52 generates a chirp signal having the chirp rate α', that is, a transmission signal whose frequency changes according to the chirp rate α'.
The signal generation unit 52 outputs the generated transmission signal to each of the transmission unit 63 and the reception unit 54.

Transmission gain setting unit 62, 'receives the regulation value EIRP and chirp rate alpha' chirp rate alpha chirp rate setting unit 61 based on the sets the transmission gain G _Tx of the transmitted signal.
The transmission gain setting unit 62 _{outputs the set transmission gain GTx} to the transmission unit 63.
_{Hereinafter, the transmission gain GTx} setting process by the transmission gain setting unit 62 will be specifically described.

First, the transmission gain setting unit 62 calculates _{the attenuation rate L rop'of the} transmission power density SP by substituting the chirp rate α'into the following equation (6).

However, when the chirp ratio α'is equal to or less than the square value of the _{filter width f RBW , L rop} '= 1.
Next, the transmission gain setting unit 62, the transmission power _{P 0} of the frequency constant transmission signal, the regulation values EIRP and attenuation factor _{L prop} ', by substituting the following equation (7), the transmission gain _{G Tx} calculate.

The transmission gain setting unit 62 outputs the calculated transmission gain _GTx to the transmission unit 63.

Depending on the chirp rate α'set by the chirp rate setting unit 61, the transmission power density SP of the transmission signal generated by the signal generation unit 52 may be larger than the regulated value EIRP, as shown in FIG. FIG. 8 is an explanatory diagram showing an example of a transmission power density SP larger than the regulation value EIRP.
When the transmission power density SP is larger than the regulated value EIRP, transmission gain G _Tx calculated by the transmission gain setting unit 62, as shown in FIG. 9, by lowering the transmission power density SP, the transmission power density SP It is a gain that matches the regulation value EIRP. At this time, the transmission gain G _Tx becomes smaller than 1. 9, the transmission gain G _Tx, is an explanatory diagram showing a state of lowering the high transmission power density SP to the restriction value EIRP.

Depending on the chirp rate α'set by the chirp rate setting unit 61, the transmission power density SP of the transmission signal generated by the signal generation unit 52 may be smaller than the regulated value EIRP, as shown in FIG. FIG. 10 is an explanatory diagram showing an example of a transmission power density SP smaller than the regulation value EIRP.
When the transmission power density SP is smaller than the regulated value EIRP, transmission gain G _Tx calculated by the transmission gain setting unit 62, as shown in FIG. 11, by increasing the transmission power density SP, the transmission power density SP It is a gain that matches the regulation value EIRP. At this time, the transmission gain G _Tx becomes larger than 1. 11, the transmission gain G _Tx, is an explanatory diagram showing a state of raising the low transmission power density SP to the restriction value EIRP.
Further, depending on the chirp rate α'set by the chirp rate setting unit 61, the transmission power density SP of the transmission signal generated by the signal generation unit 52 may be the same as the regulation value EIRP.
When the transmission power density SP is the same as the regulated value EIRP, transmission gain G _Tx calculated by the transmission gain setting unit 62, a gain does not change the transmission power density SP. At this time, the transmission gain G _Tx becomes 1.

_{When the transmission unit 63 receives the transmission gain G Tx} from the transmission gain setting unit 62, the transmission unit 63 multiplies the transmission gain G _Tx by the transmission signal generated by the signal generation unit 52.
The transmission unit 63 outputs the transmission signal after the transmission gain multiplication to the transmission antenna 18, so that the transmission signal is transmitted from the transmission antenna 18.

In the above second embodiment, the chirp rate setting unit 61 that sets the chirp rate α'of the transmission signal, and the chirp rate α'set by the regulation value EIRP of the transmission power density SP in the transmission signal and the chirp rate setting unit 61. based on the bets, the transmission gain setting unit 62 for setting a transmission gain G _Tx of the transmitted signal, a signal generator 52 for generating a transmission signal whose frequency varies by the chirp rate alpha 'set by the chirp rate setting unit 61 , to include a transmitting unit 63 that multiplies the transmission signal generated transmission gain G _Tx set by transmitting the gain setting unit 62 by the signal generation unit 52 transmits the transmission signal after transmission gain multiplication, the transmission device 1 was configured. Therefore, the transmission device 1 can be used even in an environment where the transmission power density SP is regulated.

In the transmission apparatus 1 shown in FIG. 7, the transmission gain setting unit 62, transmission power density SP of the transmission signal to be transmitted is calculated transmission gain G _Tx as to match the regulated value EIRP by transmitter 63.
However, this is only an example, transmission gain setting unit 62, transmission power density SP of the transmission signal transmitted by the transmission unit 63 may calculate the transmission gain G _Tx smaller than the regulated value EIRP .. If the transmission power density SP of the transmission signal transmitted by the transmission unit 63 is smaller than the regulated value EIRP, the transmission device 1 can be used even in an environment where the transmission power density SP is regulated. However, if the transmission power density SP of the transmission signal transmitted by the transmission unit 63 becomes too smaller than the regulation value EIRP, it may be difficult for the receiving device 2 to receive the transmission signal transmitted from the transmission device 1. .. Therefore, even if the transmission power density SP of the transmission signal transmitted by the transmission unit 63 is smaller than the regulation value EIRP, the transmission gain setting unit 62 has a transmission gain in which the transmission power density SP is close to the regulation value EIRP. It is desirable to calculate G _Tx.

In the present invention, within the scope of the invention, it is possible to freely combine each embodiment, modify any component of each embodiment, or omit any component in each embodiment. ..

The present invention is suitable for a transmission device that transmits a transmission signal and a transmission / reception device that transmits a transmission signal and generates a reception signal.

1 Transmitter, 2 Receiver, 11 EEPROM, 12 FPGA, 13 Clock, 14 DDS, 15 BPF, 16 div, 17 ATT, 18 Transmit Antenna, 21 Receive Antenna, 22 BPF, 23 LNA, 24 MIX, 25 LPF, 26 ADC, 27 processor, 28 memory, 29 data storage, 30 display unit, 51 charp rate setting unit, 52 signal generation unit, 53 transmitter unit, 54 receiver unit, 55 signal processing unit, 61 charp rate setting unit, 62 transmission gain setting Department, 63 Transmission part.

Claims (6)

1. A chirp rate setting unit that sets the chirp rate of the transmission signal based on the regulation value of the transmission power density in the transmission signal, and a chirp rate setting unit.
   A signal generation unit that generates a transmission signal whose frequency changes according to the chirp rate set by the chirp rate setting unit, and a signal generation unit.
   A transmission device including a transmission unit that transmits a transmission signal generated by the signal generation unit.
2. A chirp rate setting unit that sets the chirp rate of the transmitted signal,
   A transmission gain setting unit that sets the transmission gain of the transmission signal based on the regulation value of the transmission power density in the transmission signal and the chirp rate set by the chirp rate setting unit.
   A signal generation unit that generates a transmission signal whose frequency changes according to the chirp rate set by the chirp rate setting unit, and a signal generation unit.
   A transmission device including a transmission unit that multiplies the transmission gain set by the transmission gain setting unit by the transmission signal generated by the signal generation unit and transmits the transmission signal after the transmission gain multiplication.
3. In the transmission gain setting unit, the transmission power density of the transmission signal generated by the signal generation unit is larger than the regulation value, or the transmission power density of the transmission signal generated by the signal generation unit is higher than the regulation value. The transmission device according to claim 2, wherein if the value is small, the transmission gain of the transmission signal is set in order to match the transmission power density of the transmission signal with the regulation value.
4. The transmitter according to any one of claims 1 to 3,
   A transmitting / receiving device including a receiving device having a receiving unit that generates a received signal from a signal received by a receiving antenna and a transmitting signal generated by the signal generating unit.
5. The transmission / reception device according to claim 4, wherein the reception device includes a signal processing unit that adds a plurality of reception signals repeatedly generated by the reception unit.
6. The transmission / reception according to claim 4, wherein the receiving device includes a signal processing unit that calculates a correlation between a transmission signal generated by the signal generation unit and a reception signal generated by the reception unit. apparatus.

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