WO2020166235A1

WO2020166235A1 - Radio communication device

Info

Publication number: WO2020166235A1
Application number: PCT/JP2020/000240
Authority: WO
Inventors: 圭伊藤
Original assignee: 株式会社日立国際電気
Priority date: 2019-02-14
Filing date: 2020-01-08
Publication date: 2020-08-20
Also published as: JPWO2020166235A1; JP7132367B2

Abstract

The objective of the present invention is to provide a radio communication device capable of identifying a transmitting radio communication device without demodulation/decoding a transmission packet. This radio communication device is provided with: a modulation processing unit which subjects transmission data to modulation processing to generate a baseband transmission signal; a band limiting filter which performs out-of-band component suppression with respect to the baseband transmission signal; a transmission frequency converting unit which converts the baseband transmission signal into a radio frequency transmission signal; and a power amplifying unit which performs power amplification of the radio frequency transmission signal. The radio communication device is configured to change a rising power characteristic of the radio frequency transmission signal into a predetermined pattern stipulated in advance by the radio communication device and a network administrator.

Description

Wireless communication device

The present disclosure relates to a wireless communication device, and is applicable to, for example, a wireless communication device having a function of identifying a transmitting wireless communication device.

When the network administrator wants to identify the transmitting wireless communication device in the wireless communication network composed of wireless communication devices, the header of the transmission packet is embedded with information indicating some model information such as the device ID, and the header is It is common to demodulate/decode and analyze the contents of the header for identification.

JP 2005-244368 A JP, 2009-246682, A Japanese Patent Publication No. 2015-525533

However, in order to analyze the header of the transmission packet, the network manager needs to receive, demodulate, and decode using the same wireless communication device as in the wireless communication network, even though the network manager receives it.
An object of the present disclosure is to provide a wireless communication device capable of specifying a wireless communication device that transmits a transmission packet without demodulating and decoding.

Of the present disclosure, a brief description of representative ones is as follows. That is, the wireless communication device includes a modulation processing unit that performs a modulation process on transmission data to generate a baseband transmission signal, a band limiting filter that suppresses an out-of-band component with respect to the baseband transmission signal, and the base. A transmission frequency conversion unit that converts the band transmission signal into a radio frequency transmission signal, and a power amplification unit that power-amplifies the radio frequency transmission signal are provided. The wireless communication device is configured to change a rising power characteristic of the wireless frequency transmission signal into a predetermined pattern pre-arranged by the wireless communication device and the network administrator.

According to the above wireless communication device, it is possible to identify the wireless communication device without demodulating/decoding the transmitted packet.

The figure which shows the structure of the radio|wireless communication apparatus of 1st embodiment. The figure which shows the example of an operation electric power gain pattern. The figure which shows an example of the rising characteristic of the transmission signal by which the electric power was operated. The figure which shows the structure of the radio|wireless communication apparatus of 2nd embodiment. The figure which shows the structure of the transmission frequency conversion part of FIG. 1, and the variable transmission frequency conversion part of FIG. The figure which shows an example of (DELTA)f setting. The figure which shows the structure of the radio|wireless communication apparatus of 3rd embodiment. The figure which shows the structure of the variable band-limiting filter of FIG. FIG. 8 is a diagram showing an example of in-band characteristics of the variable band limiting filter of FIG. 7. The figure which shows the structure of the radio|wireless communication apparatus of 4th embodiment. The figure which shows the structure of the radio|wireless communication apparatus of 5th embodiment.

Hereinafter, embodiments will be described with reference to the drawings. However, in the following description, the same components may be assigned the same reference numerals and repeated description may be omitted.

<First embodiment>
A wireless communication device according to the first embodiment will be described with reference to FIG. FIG. 1 is a diagram showing a configuration of a wireless communication device according to the first embodiment.
The wireless communication device 100 according to the first embodiment includes a modulation processing unit 101, a band limiting filter 102, a power operation gain selection unit 103, an operation gain multiplier 104, a transmission frequency conversion unit 105, a PA unit 106, and The transmitting unit includes a transmitting antenna 107.

The modulation processing unit 101 performs modulation processing on the input transmission bit sequence (baseband signal) by the device, and generates a modulation signal (baseband transmission signal). The band limiting filter 102 suppresses a component outside the band of the transmission signal with respect to the baseband transmission signal generated by the modulation processing unit 101.

The power operation gain selection unit 103 outputs the power operation gain that changes the power characteristics for starting the transmission based on the model information. The operation gain multiplier 104 multiplies the output signal (modulation signal) of the band limiting filter 102 by the operation gain generated by the power operation gain selection unit 103 to generate a power operation baseband transmission signal.

The transmission frequency conversion unit 105 converts the power operation baseband transmission signal generated by the operation gain multiplier 104 into a radio frequency (radio frequency transmission signal) for transmission. The PA unit 106 power-amplifies the radio frequency transmission signal converted into the radio frequency by the transmission frequency conversion unit 105. The transmission antenna 107 transmits the radio frequency transmission signal amplified by the PA unit 106.

The power operation, which is a feature of this embodiment, will be described with reference to FIGS. FIG. 2 is a diagram showing an example of an operation power gain pattern, FIG. 2A is a diagram showing an example of an operation power gain pattern for increasing the gain, and FIG. 2B is a view showing an example of the operation power gain pattern. It is a figure which shows an example of an operation electric power gain pattern. FIG. 3 is a diagram showing an example of a rising edge of a power-controlled transmission signal, FIG. 3(a) is a diagram corresponding to FIG. 2(a), and FIG. 3(b) is a diagram corresponding to FIG. 2(b). FIG. The solid line in FIG. 3 shows the output characteristic of the PA unit 106 without gain operation, and the broken line shows the output characteristic of the PA unit 106 with gain operation.

Prepare multiple operating power patterns corresponding to multiple wireless communication device models in advance. For example, when the power operation gain selection unit 103 selects the operation power gain pattern as shown in FIG. 2A based on the model information, the output characteristic of the PA unit 106 becomes as shown in FIG. For example, when the power operation gain selection unit 103 selects the operation power gain pattern as shown in FIG. 2B based on the model information, the output characteristic of the PA unit 106 becomes as shown in FIG. 3B.

In the first embodiment, the power operation gain for operating the transmission startup power characteristic is selected from the model information, and by multiplying the gain, a different transmission startup power characteristic is provided for each wireless communication device. It is possible to identify the wireless communication device that is transmitting by monitoring the power characteristic with RSSI (Receive Signal Strength Indicator).

<Second embodiment>
A wireless communication device of the second embodiment will be described with reference to FIGS. FIG. 4 is a diagram showing the configuration of the wireless communication device of the second embodiment. 5A is a diagram showing the configuration of the transmission frequency conversion unit of FIG. 1, and FIG. 5B is a diagram showing the configuration of the variable transmission frequency conversion unit of FIG.
The wireless communication device 200 according to the second embodiment includes a transmission unit including a modulation processing unit 101, a band limiting filter 102, a variable transmission frequency conversion unit 205, a PA unit 106, and a transmission antenna 107. Since the modulation processing unit 101, the band limiting filter 102, the PA unit 106, and the transmission antenna 107 are the same as those in the first embodiment, the description will be omitted.

First, in order to facilitate understanding of the configuration of the variable transmission frequency conversion unit, the configuration of the transmission frequency conversion unit of the first embodiment will be described. As illustrated in FIG. 5A, the transmission frequency conversion unit 105 outputs the output signal of the band limiting filter 102 (baseband transmission signal, signal of frequency f1) to a radio frequency (fc) defined by a predetermined frequency (f2). ), a mixer (multiplier) 105a for converting into a radio frequency transmission signal, and an oscillator 105b for supplying a predetermined frequency (f2) to the mixer 105a.

Next, the configuration of the variable transmission frequency converter will be described. As shown in FIG. 5B, the variable transmission frequency conversion unit 205 offsets the output signal (baseband transmission signal, signal of frequency f1) of the band limiting filter 102 to a predetermined frequency (f2) by offset frequency (Δf). A mixer (multiplier) 205a for converting into a radio frequency transmission signal of radio frequency (fc+Δf) by the added frequency (f2+Δf) and an offset frequency (Δf) to a predetermined frequency (f2) based on model information. And an oscillator 205c that supplies the frequency (f2+Δf) to the mixer 205b.
The variable transmission frequency conversion unit 205 sets the radio frequency transmission signal of the specified radio frequency (fc) to Δf according to the model information, and converts the radio frequency transmission signal of the radio frequency of fc+Δf. That is, the variable transmission frequency conversion unit 205 can convert the baseband transmission signal into a plurality of radio frequency transmission signals based on the model information.

FIG. 6 is a diagram showing an example of Δf setting. When the horizontal axis represents the packet number and the vertical axis represents Δf, in a model of the wireless communication device, Δf is not fixed depending on the model, but Δf is changed for each packet, as shown in FIG. The pattern in which this Δf changes differs depending on the model, and this is set by the model information. Therefore, the variable transmission frequency conversion unit 205 can change the radio frequency of the radio frequency transmission signal for each packet, and can configure a plurality of radio frequency patterns. It is possible to adapt the model to a specific pattern of radio frequency.

In the second embodiment, by varying the radio frequency in a specific pattern, it is possible for the administrator of the wireless communication network to identify the wireless communication device that is transmitting by monitoring the frequency offset characteristic.

<Third embodiment>
A wireless communication device according to the third embodiment will be described with reference to FIGS. FIG. 7 is a diagram showing the configuration of the wireless communication device of the third embodiment. FIG. 8 is a diagram showing the configuration of the variable band limiting filter shown in FIG.
The wireless communication device 300 of the third embodiment includes a transmission unit including a modulation processing unit 101, a variable band limiting filter 302, a transmission frequency conversion unit 105, a PA unit 106, and a transmission antenna 107. Since the modulation processing unit 101, the transmission frequency conversion unit 105, the PA unit 106, and the transmission antenna 107 are the same as those in the first embodiment, the description will be omitted.

As shown in FIG. 8, the variable band limiting filter 302 includes a band limiting filter 303 and a filter coefficient generation unit 304. The band limiting filter 303 is, for example, a finite impulse response (FIR) type filter, and includes n delay elements 304a of a z-transform transfer function (z-1), n+1 multipliers 304b, and an adder. And a container 304c. The filter coefficients (k0, k1, k2,..., kn) are input to the n+1 multipliers 304b, respectively. The filter coefficient generation unit 304 is composed of, for example, a memory such as a ROM, and the filter coefficient corresponding to the model information is read and input to the band limiting filter 303.
The variable band limiting filter 302 changes the filter coefficient according to the model information to change the in-band characteristic of the transmission signal.

A characteristic example of the variable band limiting filter 302 will be described with reference to FIG. 9 is a diagram showing an example of in-band characteristics of the variable band limiting filter of FIG. 7, FIG. 9(a) is in-band characteristics when the first filter coefficient is set, and FIG. 9(b) is This is an in-band characteristic when the second filter coefficient is set. In FIG. 9, the horizontal axis represents frequency and the vertical axis represents level.
In the in-band characteristic of FIG. 9B, a characteristic different from that of FIG. 9A appears in a portion surrounded by a broken line circle. In this way, it is possible to change the in-band characteristics by changing the filter coefficient.

Note that the in-band characteristics are corrected by equalization processing on the receiving side, or the inverse characteristics are applied in advance during reception to minimize the effect on demodulation processing.

In the third embodiment, by varying the in-band characteristics of the transmission signal in a specific pattern according to the model information, the administrator of the wireless communication network identifies the wireless communication device transmitting by monitoring the spectrum. It is possible.

<Fourth Embodiment>
A wireless communication device according to the fourth embodiment will be described with reference to FIG. FIG. 10 is a diagram showing the configuration of the wireless communication transmitter of the fourth embodiment.
The wireless communication device 400 of the fourth embodiment includes a modulation processing unit 101, a variable band limiting filter 302, a power operation gain selection unit 103, an operation gain multiplier 104, a variable transmission frequency conversion unit 205, and a PA unit 106. And a transmitting antenna 107.
The modulation processing unit 101, the power operation gain selection unit 103, the operation gain multiplier 104, the PA unit 106, and the transmission antenna 107 are the same as in the first embodiment, and the variable transmission frequency conversion unit 205 is the same as in the second embodiment. Since the variable band limiting filter 302 is the same as that of the third embodiment, its description is omitted.

The wireless communication device 400 of the fourth embodiment performs the operation of the power characteristic of the first embodiment, the operation of the transmission radio frequency of the second embodiment, and the operation of the band characteristic of the third embodiment in parallel based on the model information. This is what you do.

In the fourth embodiment, the wireless communication device that is transmitting is specified by monitoring the transmission characteristics such as the power characteristics, the transmission radio frequency, and the in-band characteristics that are changed according to the model information. Is possible.

<Fifth Embodiment>
A wireless communication device of the fifth embodiment will be described with reference to FIG. FIG. 11 is a diagram showing the configuration of the wireless communication device of the fifth embodiment.
The wireless communication device 500 according to the fifth embodiment includes a modulation processing unit 101, a variable band limiting filter 302, a power operation gain selection unit 103, an operation gain multiplier 104, a variable transmission frequency conversion unit 205, and a PA unit 106. And a transmitting antenna 107 and pseudo random number generators 508a, 508b, 508c.
The modulation processing unit 101, the power operation gain selection unit 103, the operation gain multiplier 104, the PA unit 106, and the transmission antenna 107 are the same as in the first embodiment, and the variable transmission frequency conversion unit 205 is the same as in the second embodiment. Since the variable band limiting filter 302 is the same as that of the third embodiment, its description is omitted.

The pseudo random number generators 508a, 508b, 508c generate pseudo random numbers using, for example, a linear feedback shift register.

In the first to fourth embodiments, the variable band limiting filter 302, the power operation gain selection unit 103, and the variable transmission frequency conversion unit 205 determine the characteristics based on the model information. Pseudo-random numbers generated by the random number generators 508a, 508b, 508c are used. The pseudo random number is made different for each transmission packet, for example. By using pseudo random numbers, each characteristic becomes random.

For example, if there is a malicious eavesdropper who attempts to identify the model of the wireless communication device in the wireless communication network, applying the present embodiment causes transmission with different transmission rising characteristics for each transmission packet. It is possible to reduce the identification of the wireless communication device that is in use.

If the network administrator knows the pseudo random number generation pattern for each wireless communication device, it is possible to specify the wireless communication device that is transmitting as in the first to fourth embodiments.

In the fifth embodiment, since pseudo random numbers are used instead of model information to transmit with different transmission rising characteristics for each transmission packet, there are malicious interceptors who try to identify the wireless communication device that is transmitting. In that case it is possible to reduce that identification.

In the embodiment, the power characteristic at the rising edge of the transmission signal, the frequency offset (transmission radio frequency), and the in-band spectrum (in-band characteristic) are changed to a pattern (predetermined pattern) promised in advance by the wireless communication device and the network administrator.

In this way, by changing the rising characteristics (transmission characteristics) of the transmission signal of the wireless communication device and adding the rising pattern of the transmission signal that is promised in advance by the wireless communication device and the network administrator, the network administrator It is possible to specify the transmitting wireless communication device based on the change in RSSI without using a receiver having a decoding process.

In addition, by changing the frequency offset of the transmission signal of the wireless communication device and adding the frequency offset pattern of the transmission signal that is promised in advance by the wireless communication device and the network administrator, the network administrator can perform reception and demodulation processing. It is possible to specify the transmitting wireless communication device based on the change in frequency offset without using a wireless communication device.

Also, by changing the spectrum of the transmission signal of the wireless communication device and adding the spectrum pattern of the transmission signal promised in advance by the wireless communication device and the network administrator, the network administrator can install a receiver having demodulation/decoding processing. It is possible to specify the transmitting wireless communication device based on the spectrum change without using.

In addition, by applying the above to make the transmission characteristics random, it is possible to reduce the possibility that the transmission characteristics will appear different to malicious eavesdroppers each time and the transmitting wireless communication device is specified. It is possible to

Although the invention made by the present inventor has been specifically described based on the embodiments, the present invention is not limited to the above embodiments, and it goes without saying that various modifications can be made. For example, in the embodiment, the example in which the wireless communication device includes the transmission antenna has been described, but the transmission antenna may not be included in the wireless communication device and may be provided outside the wireless communication device.
In addition, in the fourth and fifth embodiments, an example in which all of the first to third embodiments are combined has been described, but any two may be combined.

The embodiments of the present invention can be used for a wireless communication device and a wireless communication system capable of specifying a wireless communication device without demodulating and decoding a transmission packet. This application claims the benefit of priority based on Japanese Patent Application No. 2019-024946 filed on February 14, 2019, and the entire disclosure thereof is incorporated herein by reference.

100, 200, 300, 400, 500... Wireless communication device 101... Modulation processing unit 102... Band limiting filter 103... Power operation gain selection unit 104... Operation gain multiplier 105... Transmission frequency conversion unit 106... PA unit 107... Transmission antenna 205... Variable transmission frequency conversion unit 302... Variable band limitation filter 303... Band limitation filter 304... Filter coefficient generation unit 508a, 508b, 508c... Pseudo random number generator

Claims

A modulation processing unit that performs modulation processing on transmission data to generate a baseband transmission signal,
A band limiting filter for suppressing an out-of-band component with respect to the baseband transmission signal,
A transmission frequency conversion unit for converting the baseband transmission signal in which the out-of-band component is suppressed to a radio frequency transmission signal,
A wireless communication device comprising: a power amplifier that power-amplifies the radio frequency transmission signal,
A power characteristic at the rising edge of the radio frequency transmission signal, a radio frequency of the radio frequency transmission signal, and any one or any two or all of the transmission characteristics of the in-band characteristics of the band limiting filter, , A wireless communication device configured to change in a predetermined pattern predetermined by the wireless communication device and a network administrator, or randomly.
The wireless communication device according to claim 1, further comprising:
A power operation gain selection unit that changes the transmission startup power characteristic based on model information or a pseudo random number generated for each transmission packet,
An operation gain multiplier that generates a power operation baseband transmission signal by multiplying the rise time of the power amplifier by the power operation gain generated by the power operation gain selection unit in the output signal of the band limiting filter, and
The wireless communication device configured to convert the transmission frequency baseband transmission signal to a radio frequency transmission signal.
The wireless communication device according to claim 1,
The transmission frequency conversion unit is configured to change the radio frequency of the radio frequency transmission signal by changing a frequency offset based on model information or a pseudo random number generated for each transmission packet.
The wireless communication device according to claim 1,
The wireless communication device configured to change the filter coefficient by changing the filter coefficient based on model information or a pseudo random number generated for each transmission packet.
The wireless communication device according to claim 1,
A wireless communication device configured to generate a pseudo random number for each transmission packet and randomly change the transmission characteristics for each transmission packet.